News & Views Archive
News & Views
Motivational control of sign-tracking behaviour
Learning and motivation are two psychological processes allowing animals to form and express Pavlovian associations between a conditioned stimulus (CS) and an unconditioned stimulus (UCS). However, most models have attempted to capture the mechanisms of learning while neglecting the role that motivation (or incentive salience) may actively play in the expression of behaviour. There is now a body of neurobehavioural evidence showing that incentive salience represents a major determinant of Pavlovian performance. This article presents a motivational model of sign-tracking behaviour whose aim is to explain a wide range of behavioural effects, including those related to partial reinforcement, physiological changes, competition between CSs, and individual differences in responding to a CS. In this model, associative learning is assumed to determine the ability to produce a Pavlovian conditioned response rather than to control the strength and the quality of that response. The model is in keeping with the incentive salience hypothesis and will therefore be discussed in the context of dopamine’s role in the brain.
News & Views
A GABAergic Tecto–Tegmento–Tectal Pathway in Pigeons
Previous studies have demonstrated that the optic tecta of the left and right brain halves reciprocally inhibit each other in birds. In mammals, the superior colliculus receives inhibitory γ-aminobutyric acid (GABA)ergic input from the basal ganglia via both the ipsilateral and the contralateral substantia nigra pars reticulata (SNr). This contralateral SNr projection is important in intertectal inhibition. Because the basal ganglia are evolutionarily conserved, the tectal projections of the SNr may show a similar pattern in birds. Therefore, the SNr could be a relay station in an indirect tecto–tectal pathway constituting the neuronal substrate for the tecto–tectal inhibition. To test this hypothesis, neuroscientists from the Biopsychology performed bilateral anterograde and retrograde tectal tracing combined with GABA immunohistochemistry in pigeons. Suprisingly, they found out that the SNr has only ipsilateral projections to the optic tectum, and these are non-GABAergic. Inhibitory GABAergic input to the contralateral optic tectum arises instead from a nearby tegmental region that receives input from the ipsilateral optic tectum. Thus, a disynaptic pathway exists that possibly constitutes the anatomical substrate for the inhibitory tecto–tectal interaction. This pathway likely plays an important role in attentional switches between the laterally placed eyes of birds.
News & Views
Cognition without cortex
In this issue of Trends in Cognitive Sciences, Onur Güntürkün and Thomas Bugnyar discuss how the brains of birds and mammals evolved in parallel for about 300 million years to achieve comparable cognitive abilities despite quite different neural architectures, most notably the lack of an avian cortex. They present anatomical and functional evidence that the avian pallium serves the functional role of the layered mammalian cortex. Finally, they discuss how the commonalities between avian and mammalian circuits may reveal the necessary ingredients to support intelligent behavior.
News & Views
Finally the Biopsychology lab again has a true stronghold in histology. Elisa Wiebeck has started at the first of March 2016 as our new technician. Elisa already took over control, brought in new fresh ideas and is within just a few weeks a true member of the group. Welcome Elisa! In the picture we see her on the left during her welcome party. Unfortunately, the same party also was a farewell party for Lina Stallmann who served as an intern. Lina we will miss you!
News & Views
Asymmetric Top-Down Modulation of Ascending Visual Pathways in Pigeons
In pigeons, the left hemisphere is associated with the ability to categorize objects based on experience-based behaviors. Why is this so? To find an answer to this question, biopsychologists from Bochum and Tübingen analyzed in detail the descending pathways from the visual forebrain in pigeons. The logic behind this study is the following: If top-down control would be more efficient in the left half brain, experience-based knowledge of the forebrain could modulate left-sided ascending visual information already at thalamic level. To test this idea, single units were recorded from the visual thalamic nucleus rotundus on the left and the right side while the eyes were activated with light flashes. During holding a single unit, the visual forebrain was anesthetized with lidocaine in one hemisphere, thereby blocking top-down influences. Indeed, activity patterns of rotundal neurons were differently modulated by left and right hemispheric descending systems. Thus, visual information ascending towards the left hemisphere was modulated by forebrain top-down systems at thalamic level, while right thalamic units were strikingly less modulated. This asymmetry of top-down control could promote experience-based processes within the left hemisphere, while biasing the right side towards stimulus-bound response patterns. In a subsequent behavioral task the scientists tested the possible functional impact of this asymmetry. Under monocular conditions, pigeons learned to discriminate color pairs, so that each hemisphere was trained on one specific discrimination. Afterwards the animals were presented with stimuli that put the hemispheres in conflict. Response patterns on the conflicting stimuli revealed a clear dominance of the left hemisphere. Transient inactivation of left hemispheric top-down control reduced this dominance while inactivation of right hemispheric top-down control had no effect on response patterns. Functional asymmetries of descending systems that modify visual ascending pathways seem to play an important role in the superiority of the left hemisphere in experience-based visual tasks.
News & Views
The New Phd-Generation
A brand-new generation of PhDs has started in the Biopsychology. Some are already with us since a short while, some will start very soon. But by and large, they form a new cohort – and they are all eager to come up with outstanding discoveries in the next couple of years. On Friday, the 19th of February 2016 they threw a great party to mark their appearance. Some of the novice PhDs will work with pigeons; others will explore the human brain. Just guess who is doing what…
News & Views
The neural basis of long-distance navigation in birds
Migratory birds can navigate over tens of thousands of kilometers with accuracy unobtainable for human navigators. To do so, they obviously use their brains. In this review, Biologists from Oldenburg and Biopsychologists from Bochum address how birds sense navigation- and orientation-relevant cues and where in their brains each individual cue is processed. When little is currently known, they make educated predictions as to which brain regions could be involved. They ask where and how multisensory navigational information is integrated and suggest that the hippocampus could interact with structures that represent maps and compass information to compute and constantly control navigational goals and directions. The team also suggests that the caudolateral nidopallium could be involved in weighing conflicting pieces of information against each other, making decisions, and helping the animal respond to unexpected situations. Considering the gaps in current knowledge, some of their suggestions may be wrong. However, the main aim of this theory-driven review is to stimulate further research in this fascinating field.
News & Views
Functional organization of telencephalic visual association fields in pigeons
Birds show remarkable visual abilities that surpass most of our visual psychophysiological abilities. In this study, scientists from the biopsychology investigated visual associative areas of the tectofugal visual system in pigeons. Similar to the condition in mammals, ascending visual pathways in birds are subdivided into parallel form/color vs. motion streams at the thalamic and primary telencephalic level. However, we know practically nothing about the functional organization of those telencephalic areas that receive input from the primary visual telencephalic fields. The current study therefore had two objectives: first, to reveal whether these visual associative areas of the tectofugal system are activated during visual discrimination tasks; second, to test whether separated form/color vs. motion pathways can be discerned among these association fields. To this end, pigeons were trained to discriminate either form/color or motion stimuli. The immediate early gene protein ZENK was used to capture the activity of the visual associative areas during the task. Indeed, several visual associative telencephalic structures could be identified by activity pattern changes during discriminations. However, none of these areas displayed a difference between form/color vs. motion sessions. The presence of such a distinction in thalamo-telencephalic, but not in further downstream visual association areas opens the possibility that these separate streams converge very early in birds, which possibly minimizes long-range connections due to the evolutionary pressure toward miniaturized brains.
News & Views
Reconsolidation in the Immune System
When memories are recalled, they enter a transient labile phase in which they can be impaired or enhanced followed by a new stabilization process termed reconsolidation. Meanwhile, we have more information on the neural processes that constitute this constant updating of memories stored in the synaptic weights of our brain. But we have multiple memory systems and some of them do not reside in the nervous system. It is unknown, however, whether reconsolidation is restricted to neurocognitive processes or can also be found in peripheral physiological functions as well. To answer this question, a group of psychoimmunologists from Essen and biopsychologists from Bochum used a paradigm of behaviorally conditioned taste aversion in rats to study memory-updating in learned immunosuppression. The administration of sub-therapeutic doses of the immunosuppressant cyclosporin A together with the conditioned stimulus (CS/saccharin) during retrieval blocked extinction of conditioned taste aversion and learned suppression of T cell cytokine (interleukin-2; interferon-c) production. This conditioned immunosuppression is of clinical relevance since it significantly prolonged the survival time of heterotopically transplanted heart allografts in rats. Collectively, these findings demonstrate that memories can be updated on both neural and behavioral levels as well as on the level of peripheral physiological systems such as immune functioning. A huge wide door has been opened by these insights. Memory updating seems to be a widespread process that is in no way restricted to our brain.
Hadamitzky, M., Bösche, K., Wirth, T., Buck, B., Beetz, O., Christians, U., Schniedewind, B., Güntürkün, O., Engler, H., Schedlowski, M., Memory reconsolidation abrogate extinction of learned immunosuppression, Brain, Behavior, and Immunity, 2016, 52: 40-48.
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CATEGORIES IN THE PIGEON BRAIN: A REVERSE ENGINEERING APPROACH
Pigeons are well capable to categorize visual stimuli. Now scientists of the biopsychology adopted a reverse engineering approach to study categorization learning in a novel way. Instead of training pigeons on predefined categories, they simply presented stimuli and analyzed neural output in search of categorical clustering on a solely neural level. They presented artificial, easily distinguishable colored shapes and grating while recording from the nidopallium frontolaterale (NFL), a higher visual area in the avian brain. They computed representational dissimilarity matrices to reveal categorical clustering based on the neural data. This revealed that colored shapes and gratings were differentially represented in the brain. This study gives proof-of-concept that this reverse engineering approach – namely reading out categorical information from neural data – can be quite helpful in understanding the neural underpinnings of categorization learning.
News & Views
‘Wanting’, ‘liking’, and their relation to consciousness
Most animal and human behaviors emanate from goal-directedness and pleasure seeking, suggesting that they are primarily under conscious control. However, ‘wanting’ and ‘liking’ are believed to be adaptive core subcortical processes working at an unconscious level and responsible for guiding behavior towards appropriate rewards. Here we examine whether ‘wanting’ is an inherent property of conscious goals and ‘liking’ an intrinsic component of conscious feelings. We argue that ‘wanting’ and ‘liking’ depend on mechanisms acting below the level of consciousness, explaining why individuals often struggle to enhance or refrain their motivations and emotions by means of conscious control. In particular, hyperreactivity of subcortical ‘wanting’ systems has been tied to pathological behaviors such as drug addiction and gambling disorder. In addicts, cognitive processes intended to curb drug-seeking wage a constant battle against subcortical urges to take more drug that often ends in relapse following repeated assaults. Nevertheless, we suggest that in non-pathological contexts, ‘wanting’ and ‘liking’ interact with major cognitive processes in order to guide goal-directed actions.
News & Views
Are birds “natural split-brains”? – Anatomical analysis of the anterior commissure in pigeon
In birds which do not possess a corpus callosum the anterior commissure (AC) constitutes the main interhemispheric pathway at telencephalic level. However no detailed description of the topographic organization of the AC has been performed till now. This information is not only necessary for a better understanding of interhemispheric transfer in birds, but also for a comparative analysis of the evolution of commissural systems in the vertebrate classes. Therefore researchers from the Biopsychology Department examined the fiber connections of the AC. The main differences in the interhemispheric connectivity between birds and mammals are found at two levels of structural organization. First, the AC in birds differs from the corpus callosum and the AC of mammals in its proportion of homotopic reciprocal to heterotopic unidirectional projections. In contrast to the situation in mammals, in birds only a small amount of cells interconnect the two hemispheres in a homotopic and reciprocal fashion. Instead, most of the cells project heterotopically and in unidirectional manner. Second, in birds the absolute majority of pallial areas do not participate by themselves in interhemispheric exchange. Instead, a rather small cluster of cells is key for commissural interactions. Thus, the colloquial statement that birds are “natural split-brains” is wrong, when the pallial areas are considered that interhemispherically interact via the AC. It is true, however, when taking into account how small the proportion of pallial neurons is that constitutes interhemispheric exchange.
News & Views
The Circuitry of Hunger and Sleep
Serotonin 1A receptors play a key role in eating and sleeping. Their combined action explains why we get sleepy after a good meal. But what is the circuitry of this system? To analyze that in birds, scientists from Brazil and Germany (Bochum and Düsseldorf) joint forces and revealed the distribution of 5-HT1A receptors in the hypothalamus and brainstem of birds and analyzed their potential roles in sleep and feeding. 5-HT1A receptors are concentrated in brainstem areas like periventricular hypothalamus, preoptic nuclei and circumventricular organs that receive dense serotonergic projections. Delivering of ventricular serotonin produced a complex pattern of neuronal activations in the 5-HT1A receptor-enriched preoptic hypothalamus and the circumventricular organs, which are related to drinking and sleep regulation, but only modestly affected the activity of serotonergic neurons themselves. The same procedure induced feeding and sleeping. Further detailed experiments revealed that serotonin induces feeding and sleeping by presynaptic binding to 5-HT1A receptors that are localized in periventricular diencephalic circuits.
dos Santos, T. S., Krüger, J., Melleu, F. F., Herold, C., Zilles, K., Poli, A., Güntürkün, O., Marino-Neto, J., Distribution of serotonin 5-HT1A-binding sites in the brainstem and the hypothalamus, and their roles in 5-HT-induced sleep and ingestive behaviors in rock pigeons (Columba livia), Behav. Brain Res. 2015, 295: 45-63.
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Cryptochrome 1b - A possible inductor of visual lateralization in pigeons?
The visual system of adult pigeons shows a lateralization of object discrimination with a left hemispheric dominance on the behavioural, physiological and anatomical levels. The crucial trigger for the establishment of this asymmetry is the position of the embryo inside the egg, which exposes the right eye to light falling through the egg shell. As a result, the right-sided retina is more strongly stimulated with light during embryonic development. However, it is unknown how this embryonic light stimulation is transduced to the brain as the classic photoreceptors, rods and cones, are not yet functional. Scientists from the biopsychology department now identified a photoreceptive protein inside the retina of pigeons which is also expressed during the critical phase of asymmetry induction. This protein, Cryptochrome 1b, is expressed in retinal ganglion cells. A tracing study revealed that such Cryptochrome 1b containing ganglion cells project to the optic tectum, a primary visual area in the pigeon brain. The projection pattern and the presence of Cryptochrome 1b during the critical phase of asymmetry induction suggests that Cryptochrome 1b could indeed be the missing photoreceptive instance responsible for inducing asymmetries in the visual system of pigeons.
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Understanding the relation between laterality and mental disorders
Atypical lateralization is observed significantly more often in schizophrenia patients than in the general population, which led several authors to conclude that there is a genetic link between laterality and schizophrenia. However, the molecular genetic evidence for a link between laterality and schizophrenia is weak. In the present article, a multinational team of researchers from the Biopsychology lab and the Bergen fMRI Group in Norway reviewed recent genetic evidence indicates that schizophrenia is not a single disorder but a group of heritable disorders caused by different genotypic networks leading to distinct clinical symptoms. Based on these findings, the researchers suggested a new theoretical framework in which genetic favtors are not mapped on schizophrenia as a whole but on discrete schizophrenia symptoms.
Ocklenburg, S., Güntürkün, O., Hugdahl, K. & Hirnstein, M.,Laterality ad mental disorders in the postgenomic age - A closer lool at schizophrenia and language lateralization, 2015, Neuroscience and Biobehavioral Reviews, 59, 100-110.
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Dealing with demands: Differences in task-related neuronal activity indicate different action oriented personality styles
People differ in the capacity to regulate emotions, thoughts and behaviors which are directed towards fulfilling one’s intentions. We differentiate between two personality types, termed action-orientation and state-orientation. Action oriented individuals are very efficient in pursuing their intentions. They focus on the relevant information and have no difficulties in taking the necessary steps towards their goal. Yet, state oriented individuals exhibit difficulties in these so called action control strategies. They tend to perseverate on irrelevant information, hindering them to pursue their intentions. This is why these two types are colloquially referred to as “doers” and “brooders”. While it is known that these behavioral differences exist, it is not clear as to whether they also reflect a neuronal deficit in state oriented individuals. Our results revealed that action oriented individuals inhibit more easily irrelevant information than state oriented individuals and also exhibit a different neuronal activity. Compared to state oriented individuals, action oriented individuals displayed a shorter latency of the frontocentral N2, an ERP component that reflects inhibition and cognitive control. These results show for the first time that neuronal processes are accountable for the incapacity of state oriented individuals in pursuing their goals more efficiently. Furthermore, they indicate that therapeutic interventions in different fields (e.g. overweight, addiction) would profit from a more individual perspective. While some strategies might be very successful for action oriented individuals, they might not be so for state oriented individuals.
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How is the semantic information of objects represented through EEG signals?
Oscillations of electroencephalographic (EEG) signals represent the neural activity which reflecting a mental state or cognitive process that arise from the behavioral task and sensory representations across the mental state activity. Previous studies have shown the relation between event-related EEG and sensory-cognitive representation, and have revealed that categorization of presented objects can be successfully recognized using recorded EEG signals when subjects view objects. In this study, we utilized the recording of EEG signals in conjunction with a multivariate pattern recognition technique with the aim of identifying neural activity associated with conceptual representation based on the presentation of semantic categories of objects. Using multivariate stimulus decoding methods, surprisingly, they demonstrated that object discrimination activity is apparent from the phase pattern of EEG signals across the time in low frequency bands (1-4 Hz), but not by the power of oscillatory brain signals in the same frequency band. In contrast, discrimination accuracy from the power of EEG signals has significantly higher than the performance by the phase of EEG signal in the high frequency band (20-30 Hz). Moreover, our results indicate that how the accuracy of prediction changes between various areas of the brain continuously across the time. In particular, we found that, during the object categorization task, the inter-trial phase coherence (IPC) in low frequency bands is significantly higher than other frequencies in various regions of interests. This measure is associated with decoding pattern across the time. These results suggest that the mechanism underlying conceptual representation can be mediated by the phase of oscillatory neural activity.
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Asymmetrical hippocampal networks
Functional hemispheric asymmetry is a common feature of brain organization, yet little is known about how hemispheric dominance is implemented at the neural level. Birds have a strong left-hemisphere asymmetry in navigation. Since the hippocampus plays a key role in spatial orientation, a team of biopsychologists from Bochum as well as Belgian and US American neuroscientists set out to test, if left and right hippocampi have asymmetrically organized hippocampal networks in birds. For this to reveal, they relied on resting state fMRI analyses in awake and sedated birds in scanners with extremely high magnetic field strengths. Indeed, the could show that following seeding in either an anterior or posterior region of the hippocampal formation of homing pigeons and starlings, the emergent functional connectivity maps are consistently larger following seeding of the left hippocampus. Left seedings were also more likely to result in networks that extend to the contralateral hippocampus and outside the boundaries of the hippocampus. The data support the hypothesis that broader functional connectivity is one neural-organizational property that confers, with respect to navigation, a functional dominance to the avian left hippocampus.
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What happens to the communication between the two hemispheres when the corpus callosum is missing?
Previous research indicates that callosal supression is important for the establishment of functional brain asymmetries. In this study researchers from the Biopsychology lab wondered what whould happen to callosal supression when there is no corpus callosum? They tested this in a multimethod neuroimaging approach combining functional and structural connectivity analysis in patients who were born without a corpus callosum and healthy individuals. The study revealed two important features of the corpus callosum. First, in healthy individuals, interhemispheric motor inhibition measured with fMRI is related to properties of specific motor fibers in the corpus callosum. Second, the inhibitory interaction between motor areas is diminished in patients without a corpus callosum. Interestingy, for these patients motor areas in each hemisphere showed symmetric involment in motor functions, indicating a reduced functional brain asymmetry. These results provide novel insights into callosal functions and the establishment and maintenance of functional brain asymmetries in general.
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Current Biology: Questions & Answers with Onur Güntürkün
Current Biology has a nice tradition: From time to time they feature a scientist on a full page by asking a lot questions (some of them strange). In the issue of October 19, 2015, it was Onur Güntürkün’s turn: “Do you have heroes?” (Yes, many); “If you would not have made it as a scientist, what would you have become?” (A taxi driver); “What is the best advice you’ve been given?” (You better give up the science you do), etc.
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PhD Thesis Sara letzner
On Thursday, the 3rd of September 2015, Sarah defended her PhD thesis entitled „„Einflüsse ontogenetischer Faktoren und kommissuraler Systeme auf die asymmetrische Informationsverarbeitung in der Taube (Columba livia)“. After giving a brilliant presentation, she stood the tough questions of the examination committee. Her thesis was a great mixture of neuroanatomical and behavioral studies. After close to an hour of questions, the committee unanimously decided that she had done a great job and decided to award her the title of a Dr. rer. nat. After that, Sara was dragged as “Princess of Biopsychology” on her own feudal cart through the whole building. Afterwards, Her Highness invited everybody to party.
Congratulations Sara! We are proud of you!
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* 15.8.1961 † 9.9.2015
über zwanzig Jahre warst Du an unserer Seite, warst Freundin, Kollegin und Mitstreiterin, Fels in der Brandung, treibende Kraft, Seele des Lehrstuhls, die Farbe in unserem Alltag…
Mit so vielen Menschen hast Du zusammengearbeitet, erzählt, gelacht und gefeiert: Studenten, Wissenschaftlern, Kollegen. Jeden Einzelnen von Ihnen hast Du geprägt und bist Teil Ihres Lebens geworden. In unseren Köpfen bleiben unendlich viele Erinnerungen an Dich, an Erlebnisse und Ereignisse. So viele Bilder von Dir…
Wo Du auch immer Du jetzt sein magst, unsere Gedanken, Erinnerungen und Gefühle finden den Weg zu Dir! Du bleibst uns unvergessen!
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Brain Symmetry of Whistled Turkish
Whistled languages represent an experiment of nature to test the widely accepted view that language comprehension is governed by the left hemisphere in an input-invariant manner. Indeed, the left hemisphere does the job for writing as well as atonal, tonal, signed, and clicked languages. The right hemisphere, on the other hand, is specialized to encode acoustic properties like spectral cues, pitch, and melodic lines and plays a role for prosodic communication. Would left hemispheric superiority change, when subjects had to encode a language that is constituted by acoustic properties for which the right hemisphere is specialized? Well, whistled Turkish uses the full lexical and syntactic information of vocal Turkish, and transforms this into whistles to transport complex conversations over kilometers. A group of Biopsychologists from Bochum now tested the comprehension of vocally vs. whistled syllables in native whistle-speaking people of mountainous Northeast Turkey. They discovered that whistled language comprehension relies on symmetric hemispheric contributions, associated with a decrease of left and a relative increase of right hemispheric encoding mechanisms. These results demonstrate that a language that places high demands on right hemisphere-typical acoustical encoding mechanisms creates a radical change in language asymmetries. Thus, language asymmetry patterns are importantly shaped by the physical properties of the lexical input. This paper was featured by many prime media like Science, Scientific American, The Scientist, New York Times, The New Yorker, BBC, Washington Post, CNN, and many more. It is also part of the Science podcast of August 21, 2015.
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PhD Thesis Sarah Starosta
On Thursday, the 13th of August 2015, Sarah defended her PhD thesis entitled „Neuronal and Behavioral Mechanisms of Extinction Learning and Renewal” in front of a tough IGSN examination committee. One of the examiners, Juan Rosas, had travelled all the way from Spain to Bochum for this task. As expected, Sarah did a brilliant job. Her talk was simply perfect, and she could respond in excellent and witty ways to each and every question. Despite trying in the hardest possible way, the examiners found no soft spot. It was all simply perfect. Therefore, the committee unanimously decided to award her the title Philosophiae doctoris (PhD) in Neuroscience.
Congratulations Sarah! You are outstanding!
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Sebastian Ocklenburg bekommt die venia legendi
Die Habilitation ist die höchstrangige Hochschulprüfung in Deutschland und setzt ein exzellentes wissenschaftliches Oeuvre voraus. Nach einem eingehenden Prüf-verfahren mit auswärtigen internationalen Gutachten wird bei erfolgreicher Evaluation die Lehrbefähigung (facultas docendi) vergeben. Nach einer anschließenden erfolg-reich verlaufenden Antrittsvorlesung wird zum Schluss die Lehrberechtigung ausge-sprochen. Diese heißt venia legendi („Erlaubnis zu lesen [d. h. zu lehren]“). Die venia legendi ist die höchste Auszeichnung, die eine Fakultät vergeben kann und signalisiert den Abschluss eines Prüfprozesses mit dem evaluiert wird, ob der Wissenschaftler sein Fach in voller Breite in Forschung und Lehre vertreten kann. Bei Erfolg wird die akademische Bezeichnung Privatdozent (PD) verliehen. Am 8. Juni 2015 war es für Sebastian Ocklenburg soweit. Mit seinem Vortrag „Das asymmetrische Gehirn und die Doppelhelix - Die Neurogenetik funktionaler Lateralisation" überzeugte er restlos alle, dass er diesen Titel verdient hatte und bekam die venia legendi aus den Händen von Annette Kluge, der Dekanin in spe unserer Fakultät.
Herzlichen Glückwunsch PD Dr. Sebastian Ocklenburg!!!!
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biopsychology retreat in bavaria
Towards the end of July the Biopsychology lab departed for its first grand retreat towards Bavaria. On the first morning we enjoyed the impressive research station of our host Princess Auguste von Bayern in her castle Leutstetten. Her outdoor aviaries and her insights in Social learning and Tool use of her New Caledonian Crows fascinated us as much as her heartfelt kindness. The picture was taken in front of her castle. Then came the excursion to the Max-Planck-Institute for Ornithology with lectures of Manfred Gahr, Nils Rattenborg, Henrik Brumm and Holger Görlitz. We could use their excellent facilities on Saturday for our own series of presentations, showing up future ideas and synergies in our department. The last day was spent as a guest of Auguste's father on the Ritterfestival where some of us unfortunately were sentenced to tarring and feathering. A somehow fitting punishment for members of a lab working with birds...
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Left dominance for language perception starts in the extrastriate cortex
While it is well known that the left hemisphere is more efficient than the right in most tasks involving perception of speech stimuli, the neurophysiological pathways leading to these lateralised performance differences are as yet rather unclear.
To clarify this question, a team of researchers from the University of Dresden and the Biopsychology lab recorded event-related potentials (ERPs) during tachistoscopic presentation of horizontally or vertically presented verbal stimuli in the left (LVF) and the right visual field (RVF). On the behavioural level, participants showed stronger hemispheric asymmetries for horizontal, than for vertical stimulus presentation. In addition, ERP asymmetries were also modulated by stimulus presentation format.
Moreover, sLORETA revealed that ERP left-right asymmetries were mainly driven by the extrastriate cortex and reading-associated areas in the parietal cortex. Taken together, the present study shows electrophysiological support for the assumption that language lateralisation during speech perception arises from a left dominance for the processing of early perceptual stimulus aspects.
Selpien, H., Siebert, C., Genc, E., Beste, C., Faustmann, P.M., Güntürkün, O., Ocklenburg, S., Left dominance for language perception starts in the extrastriate cortex: An ERP and sLORETA study. Behavioural Brain Research, 2015, 291: 325-333.
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From June 29th to July 3rd 2015, "EVOBRAIN 2015 - The first German-Brazilian summer school on comparative neuroscience of brain evolution" took place in one of the most exciting cities of South America, Rio de Janeiro, Brazil. Supported by the DAAD and the BMBF and organized by Nina Patzke from the Instituto de Ciências Biomédicas of the Universidade Federal do Rio de Janeiro, as well as Felix Ströckens and Sebastian Ocklenburg from the biopsychology lab, this was the second successful international workshop on comparative neuroscience co-organized by the biopsychology lab. The weeklong workshop offered promising young neuroscientists from all over Brazil an exiting mixture of talks by well-known experts in the field of comparative neuroscience, as well as lab practicals and career planing support. Special emphasis was put on research in atypical model species, and from flies to electric eels, cetaceans and star-nosed moles, reserach in a very diverse range of fascinating model species was presented. Receiving overwhelming positive feedback from all participants we agree that this summer school was a great experience and we are looking forward to further cooperations and activities with our old and new friends from Brazil.
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2. Deutsch-Türkische Wissenschaftsgespräche der Alexander von Humboldt-Stiftung und der Leopoldina in Zusammenarbeit mit der Ruhr-Universität Bochum
Anlässlich des „Deutsch-Türkischen Wissenschaftsjahres 2014-15" haben die Leopoldina und die Humboldt-Stiftung ein gemeinsames Format ins Leben gerufen – die „Deutsch-Türkischen Wissenschaftsgespräche" ("German-Turkish Science Dialogue"). Ziel ist es, den bilateralen Dialog zu fördern und die deutsch-türkische Wissenschaftskooperation zu unterstützen. Die Leopoldina nimmt als Nationale Akademie der Wissenschaften Deutschlands mit ihren rund 1500 Mitgliedern zu den wissenschaftlichen Grundlagen politischer und gesellschaftlicher Fragen unabhängig und öffentlich Stellung. Sie vertritt die deutsche Wissenschaft in internationalen Gremien und handelt zum Wohle der Menschen und der Gestaltung ihrer Zukunft. Die Alexander von Humboldt-Stiftung fördert Wissenschaftskooperationen zwischen exzellenten ausländischen und deutschen Forscher/innen.
Dienstag, 16. Juni 2015, 14:00 bis 19:00 Uhr
Ruhr-Universität Bochum, Gebäude GAFO 03 / 252, Universitätsstraße 150, 44801 Bochum
Neuroscience: From Structure to Function and Back
Eine Online-Registrierung unter www.leopoldina.org/de/science-dialogue wird bis zum 14. Juni 2015 erbeten.
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NRW-Akademie der Wissenschaften und Künste
Am 20. Mai wurde Prof. Dr. Dres. h.c. Onur Güntürkün als eines von 19 neuen Mitgliedern in der Nordrhein-Westfälischen Akademie der Wissenschaften und Künste in Düsseldorf willkommen geheißen. Mit seiner Aufnahme ist Prof. Güntürkün der erste Psychologe in der Klasse für Naturwissenschaften. Die AWK ist eine Vereinigung der führenden Forscher des Landes und die Heimat von 14 wissenschaftlichen Forschungsvorhaben. Sie wurde 1970 als Nachfolgeeinrichtung der Arbeitsgemeinschaft für Forschung des Landes Nordrhein-Westfalen gegründet.
© AWK NRW/Andreas Endermann
v. l.: RUB-Rektor Prof. Dr. Elmar Weiler, Prof. Dr. Käte Meyer-Drawe, NRW-Wissenschaftsministerin Svenja Schulze, Prof. Dr. Onur Güntürkün und Prof. Dr. Dr. Dr. Hans Hatt.
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Martina Manns becomes an Editorial Board Member for Scientific Reports
Martina Manns becomes an Editorial Board Member for Scientific Reports. This journal is a young online, open access journal from Nature Publishing Group. It publishes scientifically valid primary research from all areas of the natural and clinical sciences and is already the 5th among all multidisciplinary research journals. Martina will bring in her expertise in Cognitive Neuroscience and Developmental Biopsychology to ensure publication of scientifically valid and technically sound research.
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ZEIT Akademie: Unser Gehirn – wie wir Lernen, Denken und Fühlen
Wir sind unser Gehirn; es steuert unsere Handlungen und Gefühle. In 4 DVDs und einem Begleitbuch mit Abbildungen und weiterführender Literatur gibt Onur Güntürkün einen weit gefächerten Einblick in die Hirnforschung. Mit vielen Experimenten führt er die Zuschauer in 10 Kapiteln durch die Neurowissenschaft. Am Ende jeder Lektion diskutieren dann ZEIT-Redakteur Ulrich Schnabel und Onur Güntürkün über die Implikationen dieser Befunde. Zuerst wird der Aufbau des menschlichen Gehirns erläutert und das Prinzip der neuralen Übermittlung erklärt. Dann werden Fragen besprochen wie z. B.: Wie nehmen wir die Welt wahr? Wie lernen und wieso vergessen wir? Was ist Intelligenz und lassen sich Gedanken steuern? Wie und wieso erleben wir Emotionen? Unterscheidet sich das Denken von Männern und Frauen und wenn ja, warum? Warum haben unsere Gehirnhemisphären unterschiedliche Funktionen? Diese Inhalte werden mit Erkenntnissen der Störungen des Gehirns, sowie seiner Veränderung während der gesamten Lebensspanne verknüpft.
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Starry Starry Night
Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Now, Biologists from Oldenburg and Biopsychologists from Bochum used operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and examined the behavioural response strategies of pigeons in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. The ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. The study thus suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy.
Alert, B., Michalik, A., Helduser, S., Mouritsen, H., Güntürkün, O., Perceptual strategies of pigeons to detect a rotational centre – A hint for star compass learning? PLoS ONE, 2015, 10(3): e0119919.
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A Common Neural Code for the Processing of Odd Sounds
Imagine a regular sequence of sounds: ba – ba – ba – ba- ba… And then think of an odd sound in between: ba – ba – ta – ba- ba… Neuroscientists will record a strange evoked potential from your auditory cortex as soon as you hear the “ta”. This potential is known as mismatch negativity (MMN) and it depends on the activation of NMDA-receptors. MMNs were recorded from the brains of humans, other primates and rodents and are seen as a cortex-specific neural component that guides attention switches to changes in the environment. Now, psychiatrists from Newcastle (Australia) and Biopsychologists from Bochum investigated if an MMN-like potential can also be recorded from the auditory-cortex equivalent forebrain structure in pigeons. Indeed, an MMN-like field potential was recorded and blocked with NMDA-receptor blocker. These results are suggestive of similar auditory sensory memory mechanisms in birds and mammals that are either homologue from a common ancestor300 million years ago or resulted from convergent evolution.
Schall, U., Müller, B. W., Kärger, K., Güntürkün, Electrophysiological mismatch response recorded in awake pigeons from the avian functional equivalent of the primary auditory cortex, NeuroReport, 2015, 26: 239-244.
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Patrick Anselme studies the beauty of unpredictability in the Biopsychology lab
Last week Patrick Anselme departed from Belgium and arrived with his own DFG-grant in Bochum to start his research project. So, what is he planning to do? His research agenda starts with a simple observation: In order to survive, humans and other animals must maximise energy intake. However, sometimes strange things happen: animals start preferring an unpredictable food option which provides a lower reward rate. Thus, they gamble; But why? Do animals sometimes prefer the unpredictable since they might obtain reward sooner? Or do they try to maximize reward? In fact, both factors might be combined in gambling: individuals try to maximize gains, and unpredictability keeps their interest upright. In his project, Patrick plans to understand if the motivation to maximize reward and the unpredictability of reward can control choices in pigeons. In addition, he plans to see how dopamine determines sensitivity to these two factors since dopamine is chiefly recruited by rewards, but is also sensitive to unpredictability.
Good luck, Patrick, and welcome to the Biopsychology!!
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Blocking NMDA-receptors in the pigeon’s ‘prefrontal’ caudal nidopallium impairs appetitive extinction learning in a sign-tracking paradigm
Within the Forschergruppe 1581 “Extinction learning” we conducted a further experiment on context-dependent extinction learning under appetitive conditions. The results are now published within the special Frontiers Research Topic “Extinction learning form a mechanistic and systems perspective”. We investigated the responsibility of N-methyl-D-aspartate receptors (NMDARs) within the `prefrontal` caudal nidopallium (avian functional equivalent of mammalian prefrontal cortex) for contextual extinction learning.
The ability to flexibly adapt to new contingencies by learning and to inhibit previously acquired associations in a context-dependent manner is essential for extinction learning. To uncover neuronal network beyond the bench of aversive extinction learning we reused the previous establish sign tracking within-subject ABA-renewal paradigm (Lengersdorf et al, 2014). Here we shed light on invariant properties of the neural basis of extinction learning by employing the pigeon as a model system. Since NMDARs in prefrontal cortex have been shown to be relevant for extinction learning, we locally antagonized NMDARs through 2-Amino-5-phosphonovalerianacid (APV) during extinction learning. This slowed down extinction learning and in addition caused a disinhibition of responding to a continuously reinforced control stimulus. In subsequent retrieval sessions, spontaneous recovery was increased while ABA renewal was unaffected. The effect of APV resembles that observed in studies of fear extinction with rodents, suggesting common neural substrates of extinction under both appetitive and aversive conditions and highlighting the similarity of mammalian prefrontal cortex and the avian caudal nidopallium despite 300 million years of independent evolution.
Lengersdorf D, Marks D, Uengoer M, Stüttgen MC and Güntürkün O (2015) Blocking NMDA-receptors in the pigeon’s “prefrontal” caudal nidopallium impairs appetitive extinction learning in a sign-tracking paradigm. Front. Behav. Neurosci. 9:85. doi: 10.3389/fnbeh.2015.00085.
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New Frontiers Research Topic Ebook "Lateralization and Cognitive Systems" published
Left-right asymmetries of structure and function are a common organization principle in vertebrates brain organization, but many aspects of this fascinating phenomenom are not well understood. Over the course of the last few years, researchers from the Biopsychology lab, the Action Lab of the University of Dresden and the Bergen fMRI group edited a large, multinatioral Research Topic in Frontiers in Psychology, encompassing peer-reviewed 34 articles from leading authorities in the field of lateralization research. With cutting-edge research in different species ranging from insects to humans, the ebook highlights many of todays main sections of lateralization research and presents a valuable ressource for researchers interested in the field.
The ebook can be downloaded here:
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Investigating the neural architecture of handedness
The question, what constitutes the neural correlates of handedness has never been answeres unequivocally. In a recent paper by Guadalupe et al. (2014) (link to the original article) the authors investigated an impressively large sample of 1960 right-handed and 106 left-handed participants to answer this question. The authors compared left- and right-handers regarding the cortical surface area of 10 different candidate regions related to language, motor control and visual processing which were obtained from previous studies investigating the structural correlates of handedness in the brain. While the authors found a nominally significant association between handedness and the surface area of the left precentral sulcus, not a single effect survived statistical correction for multiple testing. Frontiers in Psychology invited a team of lateralization experts from the Biopsychology lab to comment on this important discovery in a prestigious Frontiers Commentary Article.
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Handedness and the X chromosome
Sex differences in handedness have long been known, but their molecular basis is not well understood. In the present study, a team of scientists from the IKN and the Human Genetics Lab investigated the relationship of CAG-length variation in the androgen receptor gene AR and handedness in a large sample of over 1000 participants. Mixed-handedness in men was significantly associated with longer CAG-repeat blocks and women homozygous for longer CAG-repeats showed a tendency for stronger left-handedness. These results suggest that handedness in both sexes is associated with AR CAG-repeat length, with longer repeats being related to a higher incidence of non-right-handedness. Since longer CAG-repeat blocks have been linked to less efficient AR function, these results implicate that differences in AR signaling in the developing brain might be one of the factors that determine individual differences in brain lateralization.
Arning, L., Ocklenburg, S., Schulz, S., Ness, V., Gerding, W.M., Hengstler, J.G., Falkenstein, M., Epplen, J.T., Güntürkün, O. & Beste, C., Handedness and the X chromosome: The role of androgen receptor CAG-repeat length. Sci. Rep. 5, 8325; DOI:10.1038/srep08325 (2015).
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The role of metabotropic glutamate receptor 5 in spatial extinction learning
Metabotropic glutamate (mGlu) receptors and, in particular, mGlu5 are crucially involved in forms of hippocampus-dependent synaptic plasticity that are believed to also underlie extinction learning. MGlu5 is also required for information transfer through neuronal oscillations and for spatial memory. This places this receptor in a unique position with regard to information encoding. Therefore, neurophysiologists and biopsychologists from Bochum explored the role of this receptor in context-dependent extinction learning under constant, or changed, contextual conditions. Their results support that although extinction learning in a new context is unaffected by mGlu5 antagonism, extinction of the consolidated context is impaired. This suggests that mGlu5 is intrinsically involved in enabling learning that once-relevant information is no longer valid.
André, M.A.E, Güntürkün, O., Manahan-Vaughan, D., The metabotropic glutamate receptor, mGlu5, is required for extinction learning that occurs in the absence of a context change. Hippocampus, 2015, 25: 149–158.
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Im Alltag ist der Mensch ständig mit Situationen konfrontiert, in denen früher Gelerntes nicht mehr gültig ist – Psychologen sprechen vom „Extinktionslernen“. Die damit verbundenen Mechanismen auf Verhaltens-, Hirn- und Immunebene am Beispiel von Tauben, Ratten und Menschen zu verstehen, ist Ziel der Forschergruppe 1581. Die Erkenntnisse dieser Initiative können langfristig auch der Therapie von Angstpatienten und Menschen mit Organtransplantationen zugutekommen. In der aktuellen Ausgabe des DFG-Magazins forschung berichtet Onur Güntürkün von den Untersuchungen innerhalb der Forschergruppe.
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Pigeons as a model species for cognitive neuroscience
They fly over hundreds of kilometers straight to their home. They memorize hundreds of abstract symbols, work for hours on problems without any sign of fatigue, manage logical problems like transitive inference, are in several respects cognitively on par with monkeys, have an unbelievably high frustration threshold during behavioral studies… and do all this for just a handful of grain. Pigeons have remarkable asymmetries of brain function, a reasonably well-charted nervous system and breast muscles that taste so well when served with wild mushrooms and a rich red wine gravy. In a recently published paper, Biopsychologists from Bochum have concocted a review of all the merits of pigeons as experimental animals for cognitive neuroscience. A sort of memorial that was long overdue.
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PhD Thesis – Daniel Lengersdorf
On Friday the 12th of December 2014 Daniel Lengersdorf defended his PhD thesis entitled „ Function of the pigeon nidopallium caudolaterale and hippocampus in context-dependent extinction learning under appetitive conditions”. At its core, Daniel’s thesis opens a new path on the analysis of the possibly invariant properties of the neural fundaments of extinction learning in birds and mammals. With a set of ingeniously designed behavioral experiments, Daniel managed to show the specific contribution of the avian “prefrontal cortex” and the bird hippocampus on extinction learning and on context-dependent extinction memory retrieval. In addition, Daniel was able to show the contribution of ‘prefrontal’ NMDA-receptors for these functions. In his defense, Daniel successfully managed to answer all questions that were put forward by the committee. All in all, a great performance! Therefore, the committee unanimously decided to award him the title Dr. rer. nat. Congratulations Daniel! We are truly proud of you.
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Die Gedanken sind frei
Die Neurowissenschaft ist zur Leitwissenschaft geworden. Neurowissenschaftlern wird daher vieles zugetraut. Manchmal zu vieles. Sie sollen möglichst schnell die Mechanismen des Gehirns verstehen und dadurch alle Krankheiten des Gehirns heilen; sie sollen die Organisation von Schulen „hirngerecht“ organisieren, bei der Lösung gesellschaftlicher Probleme beratend zur Seite stehen und bei vielen wissenschaftlichen Kontroversen das letzte Wort haben. Diese übertriebenen Erwartungen entstanden z. T. durch überhöhte Ankündigungen von Regierungen (z. B. „Decade of the Brain“) sowie Verlautbarungen einzelner Neurowissenschaftler in Form scheinbar wissenschaftlich gesicherter Aussagen (z. B. die Aussagen zur Willensfreiheit). Um längerfristig einem Vertrauensverlust zu begegnen, organisiert die Hertie-Stiftung zusammen mit der Frankfurter Allgemeinen Zeitung eine Vortragsreihe, bei der einmal im Monat ein Neurowissenschaftler zu einem aktuellen Thema der Hirnforschung einen öffentlichen Vortrag hält. Darin sollen die gesellschaftlichen Zuschreibungen, die tatsächliche Erkenntnislage und die möglichen wissenschaftlichen Grenzen der Neurowissenschaft bezüglich eines konkreten Themas vorgestellt werden. Am 22. Oktober 2014 hielt Onur Güntürkün an der Frankfurter Universität den Vortrag zum Thema „Denken“. Sein Vortrag mit dem Titel „Die Gedanken sind frei – aber werden sie das auch bleiben?“ erschien am 29.10.2014 in der FAZ.
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Habilitation – Sebastian Ocklenburg
Sebastian Ocklenburg successfully habilitated on the 12th of November 2014 in the Faculty of Psychology for the field of “Cognitive Neuroscience”. His written thesis already had impressed everybody by its clear focus on cerebral asymmetries and its breadth within this area of analysis. Now, he performed equally well with his oral presentation on why white matter matters. Sebastian’s presentation was absolutely lucid and perfect. He could subsequently answer all emerging questions in the best possible way. Altogether, this was a very strong presentation and the committee unanimously decided that Sebastian Ocklenburg should be awarded with the habilitation of the Faculty of Psychology.
CONGRATULATIONS SEBASTIAN !!!
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Neurons in the pigeon nidopallium caudolaterale signal the selection and execution of perceptual decisions
In the recently published paper we focused on the investigation of generality in neural mechanisms underlying perceptual decision making across species. Therefore, we recorded single-neuron activity in the pigeon nidopallium caudolaterale (NCL). This area is a non-laminated associative forebrain structure thought to be functionally equivalent to mammalian prefrontal cortex. The freely moving subject performed a well established visual categorisation task. Whereas the majority of NCL neurons unspecifically upregulated or downregulated activity during stimulus presentation, ~20% of neurons exhibited differential activity for the sample stimuli and predicted upcoming choices. Moreover, neural activity in these neurons was ramping up during stimulus presentation and remained elevated until a choice was initiated. This response pattern is similar to that found in monkey prefrontal and parietal cortices in saccadic choice tasks. In addition, many NCL neurons coded for movement direction during choice execution and differentiated between choice outcomes (reward and punishment). By means of these results we further implicate the NCL to be involved in the selection and execution of operant responses, an interpretation resonating well with the results of previous lesion studies. The resemblance of the response patterns of NCL neurons to those observed in mammalian cortex suggests that, despite differing neural architectures, mechanisms for perceptual decision making are similar across classes of vertebrates.
Lengersdorf, D., Pusch, R., Güntürkün, O., Stüttgen, M.C. (2014). Neurons in the pigeons nidopallium caudolaterale signal the selection and execution of perceptual decisions. Eur J Neurosci, 40, 3316-3327.
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Geist – Gehirn – Genom – Gesellschaft: Wie wurde ich zu der Person, die ich bin?
Die Frage „Wie wurde ich zu der Person, die ich bin?“ betrifft jeden ganz unmittelbar. Wenn man möglichst umfassend verstehen will, welche Bedingungen, Prozesse und Einflussfaktoren dazu beitragen, dass wir in der Interaktion mit unserer Umwelt zu einzigartigen Individuen werden, muss man das Panorama des gegenwärtigen Wissens über die natürlichen und kulturellen Wurzeln menschlicher Individualität aus den unterschiedlichsten wissenschaftlichen Perspektiven betrachten. Alte Erklärungsmodelle, die Eigenschaften und Leistungsvermögen eines Menschen entweder auf das Erbgut oder auf Umwelteinflüsse zurückführten, werden abgelöst durch neue Erkenntnisse über die Wechselwirkung dieser Faktoren. Doch wie genau resultiert der einzelne Mensch aus der Ko-Konstruktion von Geist, Gehirn, Genom und Gesellschaft? Die Leopoldina hatte ihre Jahresversammlung 2013 dieser Frage gewidmet. Unter dem Motto „Geist – Gehirn – Genom – Gesellschaft. Wie wurde ich zu der Person, die ich bin?“ haben vom 20. bis 22. September 2013 in Halle Vertreter der unterschiedlichsten Disziplinen aus Sicht ihrer Fachgebiete dargestellt, wie wir Individuen aus dem Zusammenspiel von Geist, Gehirn, Genom und Gesellschaft resultiert. Nun ist der Tagungsband erschienen, der fast alle auf der Jahresversammlung gehaltenen Vorträge enthält (Güntürkün, O., Hacker, J. (Hrsg.), Nova Acta Leopoldina Nr. 405, Band: 120, Geist – Gehirn – Genom – Gesellschaft: Wie wurde ich zu der Person, die ich bin? Wissenschaftliche Verlagsgesellschaft Stuttgart, 2014.). Der untere Link öffnet den Eröffnungsvortrag zur Jahrestagung von Onur Güntürkün.
Güntürkün, O., Geist – Gehirn – Genom – Gesellschaft: Wie wurde ich zu der Person, die ich bin? In: Nova Acta Leopoldina Nr. 405, Band: 120, Geist – Gehirn – Genom – Gesellschaft: Wie wurde ich zu der Person, die ich bin? Güntürkün, O., Hacker, J. (Eds.), Wissenschaftliche Verlagsgesellschaft Stuttgart, 2014, pp. 11-35.
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IMPRessions from the DGPs congress on dasgehirn.info
www.dasGehirn.info provides information on the brain, its functions and its importance to our feelings, thoughts and actions - comprehensive, readable, attractive and clearly in words, pictures and sound. This time, the online magazine informs about the 49th Congress of the German Society for Psychology (DGPs) in Bochum. This year's motto was "Diversity of Psychology". At the same time the Institute of Psychology was celebrating its 50th anniversary. Learn more about envy, nuts and more and see the video here.
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dasGehirn.INFO informs about FOR 1581
The online magazine www.dasGehirn.info informs the reader about findings of brain research in an entertaining and comprehensive way. In cooperation with the research groups FOR 1581 and SFB 636 they present extinction learning as one of the most exciting current research topics between mind and brain. As old knowledge is persistent - especially under stress -, the initial process of acquisition of new knowledge is well studied, but the process of extinction is far less understood. Read more.
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Onur Güntürkün started his fellowship at the Wissenschaftskolleg zu Berlin and Martina Manns substitutes him during WS 2014/15
Onur Güntürkün will stay from October 2014 to April 2015 in Berlin Grunewald together with about 50 other researchers from all over the world to think deeply about scientific problems. During this time, he wants to explore if it is possible that the capacity for complex cognition arose several times during evolution such that groups of non-mammalian animals might have developed as-yet unknown brain mechanisms that generate intelligent behavior. His ideas may contribute to developing a new theory of the evolution of brains and complex cognitive abilities.
In the meantime during WS 2014/15, Martina Manns acts for a substitute professor of the Biopsychology. Apart from taking over teaching, she will pursue investigating development of cerebral asymmetries in pigeons to unravel the interactions of left- and right-hemispheric specialization processes.
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How white matter influences functional asymmetry
Structural asymmetries in white matter tracts within the language system have been suggested to be one of the factors underlying functional language lateralization. To test this assumption, researchers from Bergen, Norway, and the biopsychology lab in Bochum examined how performance in the dichotic listening task is affected the structure of the arcuate and uncinate fasciculus, assessed with DTI. Both arcuate and uncinate fasciculus had a larger tract volume in the left compared to the right hemisphere, but fractional anisotropy was higher in the right than in the left arcuate fasciculus. Interestingly, structural asymmetries were linked to functional lateralization, that is, tract volume and fractional anisotropy of the left arcuate fasciculus were positively correlated to the strength of functional language lateralization, as was the volume of the right uncinate fasciculus. These results suggest that both micro- and macro-structural properties of language-relevant intrahemispheric white matter tracts modulate the behavioral correlates of language lateralization.
Ocklenburg, S., Schlaffke, L., Hugdahl, K., Westerhausen, R. (2014). From structure to function in the lateralized brain: How structural properties of the arcuate and uncinate fasciculus are associated with dichotic listening performance. Neuroscience Letters, 580: 32-36.
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PhD Thesis – Nils Kasties
On Friday the 11th of July 2014 Nils Kasties defended his PhD thesis entitled „Neuronal foundations of decision making in the pigeon nidopallium caudolaterale”. …And what a defense it was!!! Nils presented two major experiments and perfectly embedded them into the current literature. In the end, he was able to integrate his findings into a model of decision making in the avian forebrain. Afterwards, Nils bravely and successfully defended his arguments for a full hour against a whole barrage of counterarguments until the members of committee were exhausted and were just yearning for sparkling wine and party. But before the party could start, members of the committee unanimously decided to award Nils the title Dr. rer. nat. Congratulations Nils! We are proud of you. In the picture you can see Nils with his two advisors on his PhD-cart with which he was drawn back to the lab.
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RECORding single unit activity in the freely moving pigeon
Learning is a fundamental ability of all organisms and the underlying neuronal mechanisms are highly conserved across species. To understand the mechanisms of learning at the single neuron level, we seek to record the activity of individual neurons across different learning stages. With this goal, RUB biopsychologists designed a behavioral task which encompassed three learning stages in a single experimental session. They made use of the keenness of pigeons in operant tasks who are willing to perform a vast amount of trials (>1000) for a relatively low amount of reinforcers. In addition, several methodological measurements were implemented to improve and control recording quality. To sum up and conserve the used methodological standards, we published a video article in the Journal of Visualized Experiments (JoVE), where the sophisticated behavioral paradigm as well as our methodological inventions are visualized and described in detail.
Starosta, S., Stüttgen, M. C., Güntürkün, O. (2014). Recording Single Neurons' Action Potentials from Freely Moving Pigeons Across Three Stages of Learning. J. Vis. Exp. (88), e51283, doi:10.3791/51283.
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Is Dolphin Cognition Special?
Recently, the government of India decided by law that "cetaceans...should be seen as 'non-human persons' and as such should have their own specific rights." This decision results from the political pressure, the public opinion, and the work of a small group of scientists who argue that dolphins have an intelligence that comes close to humans. In Germany activists and members of the Green Party demand that the dolphinaries in Duisburg and Nürnberg be closed. But how strong is the scientific evidence for the cognitive exceptionality of dolphins? Paul Manger [Neuroscience, 2013] reviewed the dolphin cognition literature and drew a quite sobering conclusion. But is his critique justified or does he throw the baby out with the bathwater? In an invited review to Brain, Behavior and Evolution (2014), Onur Güntürkün summarizes the literature on dolphin cognition and compares it with evidences from other animals. He concludes that dolphin cognition is not exceptional since there is not a single achievement that has not also been shown in several other species. However, in all major areas of comparative cognitive science, dolphins have been shown to achieve fast learning, high flexibility, and a swift transfer of learned knowledge to new contingencies. So, dolphins are in many respects cognitive generalists, performing at an overall high level. So, the evolution of high cognitive skills has independently taken place in several lines of life, among them primates, cetacean (mostly dolphins), birds (mostly corvids and parrots). There seem to be many different routes to intelligence.
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The avian and the mammalian hippocampus: A divide of 300 million years
The evolutionary lines of birds and mammals diverged nearly 300 million years ago. As a consequence, the brains of these two classes of vertebrates share some features but also have many unique and non-shared properties. The hippocampus is an especially interesting case: the hippocampus of mammals and birds is homologous and thus stems from a common reptilian ancestor that already had a hippocampus. As a result, avian and mammalian hippocampi share some similar functions (e.g. spatial cognition) and anatomical features (e.g. a re-entrant loop). But they also developed a large number of bird- or mammal-typical aspects that do not seem to have counterpart. Overall, it is still mostly unknown which components of the bird hippocampus are avian-unique and which are similar to mammals. To solve these questions, scientists from Bochum, Düsseldorf, and Bowling Green (USA) analyzed binding site densities for 11 different receptor systems by using quantitative in vitro receptor autoradiography. Additionally, they labeled zinc to show a further compartmentalization of the hippocampus. The regionally different receptor densities mapped well onto seven hippocampal subdivisions previously described. Several differences in receptor expression highlighted distinct hippocampal subfields. In addition, several similarities in receptor binding densities between subdivisions of the avian and mammalian hippocampus were observed. Despite the similarities, the consortium of scientists concluded that 300 hundred million years of independent evolution has led to a vast mosaic of similarities and differences in the organization of the avian and mammalian hippocampal formation. Thinking about the avian hippocampus in terms of the strict organization of the mammalian hippocampus is likely insufficient to understand the hippocampus of birds.
Herold, C., Bingman, V. P., Ströckens, F., Letzner, S., Sauvage, M., Palomero-Gallagher, N., Zilles, K. Güntürkün, O. (2014). Distribution of Neurotransmitter Receptors and Zinc in the Pigeon (Columba livia) Hippocampal Formation: A Basis for Further Comparison with the Mammalian Hippocampus, J. Comp. Neurol., 522: 2553-2575.
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Maik Stüttgen becomes a Professor for Behavioral Neurophysiology
Since a while, rumor had it. Then it became official; and now it truly happened: Maik Stüttgen left the Biopsychology to become a Professor for Behavioral Neurophysiology at the University of Mainz. What a loss for us, what a gain for the crowd down under in Mainz! Maik truly personalized the best mixture of a young scientist who is on his way to become a great scholar: focused and dedicated, but at the same time approachable and caring for students; critical for all details but also seeing the greater picture. His PhD-students had only one phrase for him that captured it all: He’s cool, really really cool. Good luck Maik!! We will miss you a lot.
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Interhemispheric Conflicts in Pigeons
In birds each hemisphere receives visual input from the contralateral eye. Since birds have no corpus callosum, avian brains are often seen as ‘natural split brains’. But if the two hemispheres can’t interact, how do birds cope with situations, when both hemispheres are brought into conflict? Who then is in charge for a decision? If under such conditions one hemisphere completely determines the response, this is called meta-control. The aim of the current study is to test, if meta-control results from an interhemispheric conflict that would require interhemispheric interaction. If such a conflict-based interaction occurs, it should produce a delay in responding. This interaction could happen via the the commissura anterior, a small forebrain commissure that also exists in birds. To this end, biopsychologists from Bochum trained pigeons in a forced-choice color discrimination task under monocular condition such that each hemisphere was trained with a different pair of colors. Subsequently, pigeons were binocularly tested with conflicting and non-conflicting stimulus patterns. Conflicting stimuli indeed produced a delayed reaction time as expected when two divergent decisions create a conflict. Thus, pigeons indeed undergo interhemispheric conflict during meta-control even without a corpus callosum. Their hemispheres then possibly interact via the commissura anterior.
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AGGRESSION AND THE ROLE OF SEROTONIN IN CHICKEN
The European Union keeps millions of chicken for egg production. These animals often engage in severe feather pecking and sometimes even in cannibalistic behavior. Obviously, this causes serious welfare problems. To study the neural mechanisms of severe feather pecking, Pharmacologists from Utrecht and Wageningen universities as well as Biopsychologists from Bochum used divergent genetic lines that were selected for high or low feather pecking. These birds were analyzed for possible differences in central serotonin (5- HT) and 5-HIAA release in the limbic and prefrontal subcomponents of the caudal nidopallium by in vivo microdialysis. The results revealed that hens bred for high severe feather pecking had higher baseline levels of 5-HT in the caudal nidopallium but no differences in plasma tryptophan levels (precursor of 5-HT) and also no differences in presynaptic 5-HT storage. Thus, the data show that high aggressive encounters under industrial poultry conditions are associated with higher 5-HT releases in the prefrontal and limbic nidopallium.
Kops, M.S., Kjaer, J. B., Güntürkün, O., Westphala, K.G.C., Korte-Bouwsa, G.A.H., Olivier, B., Bolhuis, J.E., Korte, S.M. (2014). Serotonin release in the caudal nidopallium of adult laying hens genetically selected for high and low feather pecking behavior: An in vivo microdialysis study. Behav. Brain Res., 268: 81-87.
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How language lateralization develops – A new view
Language lateralization is one of the areas of main interest in research on human lateralization, but it is not well understood which molecular genetic factors influence this trait. Classic theories about its ontogenesis assume that it is determined by the same ontogenetic factors as handedness. In the present article, scientists from the IKN and the department of human genetics argue, that this view is contradicted by recent neuroimaging and genetics studies. Therefore, we argue that although the two traits show partial pleiotropy, there is also a substantial amount of independent ontogenetic influences for each of them. This view is supported by several recent genetic and neuroscientific studies that are reviewed in the present article.
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Functional and structural comparison of visual lateralization in birds - similar but still different.
What are the neuronal and ontogenetic foundations of cerebral asymmetries? This question is deeply investigated in two avian model systems: chickens and pigeons. It is well known that the brains of these animals display physiological and anatomical left-right differences, which are related to hemispheric dominances for specific functions. In both species, asymmetrical light stimulation during embryonic development induces a dominance of the left hemisphere for visuomotor control. Nevertheless, the underlying structural asymmetries vary essentially between both species. In this recent paper, scientist from the biopsychology lab analyzed existent data on this rather puzzling phenomenon. They found evidence that although early asymmetric light stimulation is defining the dominant hemisphere for visuomotor tasks, the structural mechanisms mediating this dominance can differ between species. Furthermore, they found that environmental stimulation likely affects the balance between hemispheric-specific processing by lateralized interactions of bottom-up and top-down systems. These findings show how the interplay between environmental factors and genetically determined lateralizations can shape functional asymmetries during early development.
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Transient inactivation of the pigeon hippocampus or the nidopallium caudolaterale during extinction learning impairs extinction retrieval in an appetitive conditioning paradigm
Extinction learning is an extensively investigated field of research with a general focus on fear conditioning experiments. Scientists at the Biopsychology lab shed more light on context-specific extinction learning under appetitive conditions. Here, extinction learning refers to the cessation of previously reinforced conditioned responding once reinforcement is withheld. To study the context dependency of extinction learning under appetitive conditions, we adopted and modified a within-subject ABA renewal paradigm from Robert Rescorla (Q J Exp Psychol 61: 1793) and performed pharmacological interventions to investigate fundamental neural mechanisms underlying context-dependent extinction learning. More specifically, we transiently inactivated either the nidopallium caudolaterale (NCL, functional equivalent of mammalian prefrontal cortex) or the hippocampus immediately before extinction training with tetrodotoxin. Both structures are core structures for context-specific extinction learning in fear conditioning paradigms. Using an elegantly controlled procedure, we found that both manipulations lead to non-specifically response suppression. Retrieval testing under drug-free conditions showed that subjects did successfully retrieve extinction memory in the context of acquisition but were impaired when tested in the context of extinction. Thus, the present study suggests that both NCL and hippocampus are involved in the consolidation of extinction memory, and that their contribution to extinction is context-specific.
Within a follow-up experiment we currently explore the function of NMDA-receptor in the NCL for extinction learning.
Lengersdorf, D., Stüttgen, M.C., Uengoer, M., Güntürkün, O. (2014).Transient inactivation of the pigeon hippocampus or the nidopallium caudolaterale during extinction learning impairs extinction retrieval in an appetitive conditioning paradigm. Behav Brain Res, 265: 93-100.
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Onur Güntürkün Wins 2014 Communicator Award
Biopsychologist Onur Güntürkün is the winner of this year's Communicator Award, conferred by the Deutsche Forschungsgemeinschaft and the Donors' Association for the Promotion of Sciences and Humanities in Germany. Professor Güntürkün, from the University of Bochum, was chosen for his exemplary approaches to communicating his research on the biological foundations for animal and human behaviour to the general public and the media. The “Communicator Award” is most important prize for science communication awarded in Germany. Established in 2000, the award is bestowed on researchers who have communicated their own scientific findings and those of their peers to a wide general audience. The prizewinners are selected by a jury comprised of science journalists and experts from the fields of public relations and communications. A total of 52 researchers working in a broad range of scientific disciplines applied or were nominated for this year's Communicator Award. After a multi-stage selection process, four of these candidates were shortlisted, with Onur Güntürkün chosen as the winner. The jury was impressed by the way in which Güntürkün combined high academic quality with a dedication to communication with the public and the media.
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LIGHT AFFECTS THE ASYMMETRY OF INTERHEMISPHERIC INFORMATION TRANSFER
Hemispheric specialization represents a core feature of information processing in the brain of humans and other animals; however, separation of function can only be advantageous when communication systems coordinate, select and integrate information from both half brains. Scientists from the biopsychology lab have recently investigated how such systems work in pigeons and if they are influenced by envirotypic factors. Pigeons possess a lateralized visual system that is shaped by asymmetrical light stimulation during development. Comparing hemispheric-specific access to transfer information of pigeons with or without embryonic light experience demonstrates the light-modulated impact of interhemispheric communication systems. Stronger embryonic stimulation of the left hemisphere significantly enhances access to interhemispheric visual information, thereby reversing a right-hemispheric advantage that develops in the absence of embryonic light stimulation. This corroborates that environmental experiences can affect genetically determined asymmetries. This study delivers a further piece of evidence supporting the role of envirotypic factors on lateralization in the current nature vs. nurture debate.
Letzner, S., Patzke, N., Verhaal, J., Manns, M. (2014). Shaping a lateralized brain: Asymmetrical light experience modulates access to visual interhemispheric information in pigeons. Sci Rep, 4: 4253.
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an advice to the president
In 2013 President Barack Obama launched the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene-structure-function relationships that are not apparent from studies on single species. About 30 scientists, among them two Biopsychologists from Bochum, were invited in fall 2013 to a think tank in Janelia Farm to advice the President on the BRAIN-initiative. The main goal was to come up with a strategy to extend the comparative approach to nervous system ‘maps’ comprising molecular, anatomical, and physiological data. The hope was that this research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. To promote this research agenda, the member of the think tank recommended that teams of investigators coalesce around specific research questions and select a set of ‘reference species’ to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well annotated genome, or other strategic reasons. This will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies.
Thus, our advice to the President, hoping he will read it.
Striedter, G.F., Belgard, T.G., Chen, C.C., Davis, F.P., Finlay, B.L., Güntürkün, O., Hale, M.E., Harris, J.A., Hecht, E.E., Hof, P.R., Hofmann, H.A., Holland, L.Z., Iwaniuk, A.N., Jarvis, E.D., Karten, H.J., Katz, P.S., Kristan, W.B., Macagno, E.R., Mitra, P.P., Moroz, L.L., Preuss, T.M., Ragsdale, C.W., Sherwood, C.C., Stevens, C.F., Stüttgen, M.C., Tsumoto, T., Wilczynski, W. (2014). NSF Workshop Report: Discovering General Principles of Nervous System Organization by Comparing Brain Maps across Species. Brain Behav Evol, 83: 1-8.
Striedter, G.F., Belgard, T.G., Chen, C.C., Davis, F.P., Finlay, B.L., Güntürkün, O., Hale, M.E., Harris, J.A., Hecht, E.E., Hof, P.R., Hofmann, H.A., Holland, L.Z., Iwaniuk, A.N., Jarvis, E.D., Karten, H.J., Katz, P.S., Kristan, W.B., Macagno, E.R., Mitra, P.P., Moroz, L.L., Preuss, T.M., Ragsdale, C.W., Sherwood, C.C., Stevens, C.F., Stüttgen, M.C., Tsumoto, T., Wilczynski, W. (2014). NSF Workshop Report: Discovering General Principles of Nervous System Organization by Comparing Brain Maps across Species. J Comp Neurol, 522:1445–1453.
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Variable Evolution of Variability
Whenever we perform a movement repeatedly, we never do it exactly the same way. There is always variability. This variability in the motor output is often viewed as noise in the system. In contrast, recent findings show that variability is more than that. Motor variability plays an important role for learning of new skills and is actively produced and regulated. Part of these findings stem from research on song birds like zebra finches. During song learning – a motor skill similar to human speech – a specialized forebrain area termed lateral magnocellular nucleus of the anterior nidopallium (LMAN) conveys variability into the motor output. Interestingly, pigeons as non-song birds possess a brain region that is possibly homologous to LMAN. This region is named nidopallium intermedium medialis pars laterale (NIML). Researchers of the Biopsychology lab together with theoretical neuroscientist from the University of Bremen have devised an experiment to test the role of NIML for behavioral variability. Pigeons learned to find hidden targets that were randomly placed at different locations on a touch screen. The researchers’ results show that their experiment induces highly variably pecking behavior. However, transient pharmacological inactivation of NIML did not result in reduction of variability. Hence, the researchers argue that in contrast to LMAN the pigeon’s NIML is not associated with behavioral variability. Together with previous findings this result suggests that LMAN’s role for variability generation in song bird is an adaptation to the special demands of song that evolved from old motor pathways of a common ancestor of recent birds. In contrast, this adaptation was not necessary in the motor system of pigeons or alternatively was lost during evolution.
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Christian Beste becomes a Professor for Cognitive Neurophysiology
We all know Christian; this rare mixture of relaxed habits, boyish charm and highest profile research. He was the boss of an Emmy Noether group in the Biopsychology lab, churning out more than 40 top papers and acquiring close to 2 million euros in the few years he was leading his small research crowd. It was clear that he wouldn’t stay for long in Bochum. Not because he didn’t liked it here (in fact, he liked it a lot) but because a young scientist with such a tremendous success rate usually becomes a professor somewhere after a short while. Now this happened. Christian became a Professor for Clinical Neurophysiology at the University Clinic for Child and Adolescent Psychiatry of the Technical University Dresden. The amount of start-up, infrastructure, and personnel he got is truly remarkable. But hey, he’s worth it! Good luck Christian!! We will miss you a lot.
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PhD Thesis – Felix Ströckens
On Friday the 29th of November 2013 Felix Ströckens defended his PhD thesis entitled „Evolutionary and ontogenetic processes of neuronal lateralization in vertebrates”. The title already demonstrates the wide angle of research and insight that Felix is commanding. With his experiments and analyses Felix shows that brain asymmetries have a very old past and can emerge with subtle molecular left-right differences. Most astonishingly, Felix also shows that different anatomical asymmetries can produce nearly identical lateralized behavior. In his defense Felix stood the ground, despite partly inquisitorial questions. What an impressive performance! Therefore, the committee unanimously decided to award him the title Dr. rer. nat. Congratulations Felix! We are proud of you.
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Oxytocin: the monogamy hormone?
Love really does change your brain. Monogamous prairie voles are known to have higher levels of oxytocin receptors than promiscuous montane voles. However, if the latter are dosed with oxytocin, they adopt the monogamous behavior of their prairie cousins. Therefore, oxytocin seems to have an important role in social bonding. But now, researchers from the University Clinic in Bonn, the University of Chengdu in China, and Biopsychologists from Bochum have performed a new experiment that suggests oxytocin stimulates the reward center in the male brain, increasing partner attractiveness and strengthening monogamy. Their study included 40 young men, all of whom had been in a relationship for at least six months and reported being passionately in love with their partners. While in a brain scanner, they either inhaled oxytocin or placebo via nasal spray while they viewed pictures of either their partners, women they knew but were not dating or women they had never met. The pictures were matched so that comparison women had been rated by independent observers as being equally attractive as the partners. In the men who were given oxytocin, the reward system (ventral tegmental area, nucleus accumbens) lit up when they saw pictures of the women they loved — but not when they looked at strangers. Some of these regions were also activated by the images of the women the men knew, but not as strongly as by the pictures of their loved ones, suggesting that it made their partners more desirable. In other words, familiarity is not enough to prompt the bonding effect of oxytocin. They must be loving couples. These results suggest that oxytocin could contribute to romantic bonds in men by enhancing their partner’s attractiveness and reward value compared with other women.
Scheele, D., Wille, A., Kendrick, K.M., Stoffel-Wagner, B., Becker, B., Güntürkün, O., Maier, W., Hurlemann, R. (2013). Oxytocin enhances brain reward system responses in men viewing the face of their female partner: Proc. Natl. Acad. Sci. USA, 110: 20308-201313.
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The Neurochemistry of Aggression
People in Germany eat more than 500 million chickens every year. The living conditions of these animals are partly abysmal. Aberrant behavior occurs often and among them severe feather pecking (SFP) cause’s major problems. SFP results in loss of feathers, skin damage and cannibalism. Now, a group of Animal Scientists from the Netherlands and Biopsychologists from Bochum studied the neurochemistry of aggression in two consecutive publications. They demonstrated that chickens with a lower tendency for SFP were less anxious and had lower levels of dopamine and serotonin turnover in somatomotor areas of the forebrain. In addition, they demonstrated that brain monoamine levels in brain areas that are involved in emotional behavior or are part of the basal ganglia-thalamopallial circuit are different in SFP-birds after a short stress period. In summary, these findings indicate that especially serotonergic neurotransmission in the dorsal thalamus, somatomotor forebrain, and striatum of hens depends on differences in behavioral feather pecking phenotype. These data show that stressful living conditions alter the serotonergic system in some individuals, leading to higher levels of anxiety and aggression.
Kops, M.S., de Haas, E. N., Rodenburg, T. B., Ellend, E. D., Korte-Bouws, G. A. H., Olivier, B., Güntürkün, O., Korte, S.M., Bolhuis, J. E. (2013). Selection for low mortality in laying hens affects catecholamine levels in the arcopallium, a brain area involved in fear and motor regulation: Behav. Brain Res., 257: 54-61
Kops, M.S., de Haas, E.N., Rodenburg, T.B., Ellend, E.D., Korte-Bouws, G.A.H., Olivier, B., Güntürkün, O., Bolhuis, J. E., Korte, E.M. (2013). Effects of feather pecking phenotype (severe feather peckers, victims and non-peckers) on serotonergic and dopaminergic activity in four brain areas of laying hens (Gallus gallus domesticus): Physiol. Behav., 120: 77-82
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Handedness: A new view
Whether we are right- or left-handed is an important aspect of our everyday life and it comes to no surprise that handedness is the single most studied aspect of human brain asymmetries. For long it has been thought to be a monogenic trait but a single gene explaining a sufficient amount of phenotypic variance has not been identified. In the present review article, researchers from the IKN give an overview about the results of several recent studies using advanced molecular genetic techniques which suggest that a multifactorial model taking into account both multiple genetic and environmental factors, as well as their interactions, might be better suited to explain the complex processes underlying the ontogenesis of handedness. New insights into handedness genetics provided by these studies are reviewed and it is discussed, how integrating results from genetic and neuroscientific studies might help to generate more accurate models of the ontogenesis of handedness. Based on these thoughts, several new candidate gene groups whose investigation would help to further understand the complex relation of genes, the brain and handedness are discussed.
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PHD TheSis - Franziska labrenz
On Friday the 22nd of November Franziska Labrenz defended her PhD thesis entitled „May I capture your attention? A neurophysiological investigation into intrinsic and extrinsic determinants of visual selective attention.” Already her written thesis was impressive in the breadth of studies and methods Franziska applied to pursue her research question. In her defense she presented a marvelous talk about her main findings of the thesis, where she showed mastery in the topic of visual selective attention and important modulators of the mechanisms. It was a really impressive talk in a matchless “Franziska style”. It was a great time having you in the lab of the Emmy Noether Research group in Bochum. Congratulations Franziska!
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THE type of implicit motive enactment is modulated by sex hormones in naturally cycling women
Sex hormones have been reported to dynamically modulate the expression of implicit motives. In the present study, a team of researchers from Biopsychology, Cognitive Psychology and the Department of Psychiatry, Psychotherapy, Psychosomatics and Preventive Medicine used the Operant Motive Test (OMT) to investigate to what extent the need for affiliation, power, and achievement is affected by the menstrual cycle. In addition to measuring the strength of motive expression, the OMT also captures different forms of motive enactment. No evidence for cycle-phase related variation in overall motive scores was found. However, when different forms of motive enactment were considered, an effect of menstrual cycle was observed. The incentive-based inhibition of the power motive was significantly reduced at the time of ovulation, compared to the menstrual and to the mid-luteal phase, in naturally cycling women. In women using hormonal contraceptives, no significant changes in the form of motive enactment were evident. These results show a hormonal influence on motive-related cognitive processes.
Ball, A., Wolf, C.C., Ocklenburg, S., Brüne, M., Wolf, O.T., Güntürkün, O., Pinnow, M. (2014). The type of implicit motive enactment is modulated by sex hormones in naturally cycling women: Physiology & Behavior, 123: 119-126
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Lateralization of face perception
The efficacy of executive functions depends on information processing in earlier cognitive stages. For example, initial processing of verbal stimuli in the left-hemisphere leads to more efficient response inhibition than initial processing of verbal stimuli in the right hemisphere. However, it is unclear whether this organizational principle is specific for the language system, or a general principle that also applies to other types of lateralized cognition. To answer this question, a team of IKN neuroscientists investigated the neurophysiological correlates of early attentional processes, facial expression perception and response inhibition during tachistoscopic presentation of facial ‘Go’ and ‘Nogo’ stimuli in the left and the right visual field. Participants committed fewer false alarms after Nogo-stimulus presentation in the left compared to the right visual field. This right-hemispheric asymmetry on the behavioral level was also reflected in the neurophysiological correlates of face perception, as well as in ERPs related to response inhibition. These findings show that an effect of hemispheric asymmetries in early information processing on the efficacy of higher cognitive functions can be generalized to predominantly right-hemispheric functions.
Ocklenburg, S., Ness, V., Güntürkün, O., Suchan, B., Beste, C. (2013). Response inhibition is modulated by functional cerebral asymmetries for facial expression perception: Frontiers in Psychology, 4:879, doi: 10.3389/fpsyg.2013.00879
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DFG approves 3-year extension of funding for research unit on extinction learning
The German Research Foundation (DFG) has recently approved funding of the research unit "Extinction Learning: behavioral, neural, and clinical mechanisms", encompassing workgroups at the Universities of Bochum, Duisburg-Essen, and Marburg, for another three-year period. Extinction learning is a basic behavioral phenomenon in which an organism learns that two events which used to occur jointly have ceased doing so. Unlike acquisition, i.e. original learning, extinction is highly context-specific, which is one of the many indications that extinction is not just "unlearning" but constitutes a novel learning process distinct from original acquisition. Although extinction was first described more than 100 years ago by Russian physiologist Ivan Pavlov, many aspects of this phenomenon are still poorly understood. This is unfortunate, given that theories on the development and treatment of psychiatric disorders in part rely on extinction - e.g. psychotherapeutic interventions for phobias or psychological treatment of drug abuse. In the next three years, the research unit is expected to make significant contributions to our understanding of the neural and behavioral mechanisms of extinction learning. The scope of the projects within the unit ranges from basic research in animal models and humans to clinical applications in the treatment of phobias, enabling efficient transfer of insight gained from basic research to outpatients seeking treatment for anxiety disorders.
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Pathways to asymmetry - how white matter asymmetries influence language lateralization
Functional hemispheric asymmetries of speech production and perception are a key feature of the human language system, but their relation to microstructural asymmetries in language-relevant white matter pathways is still poorly understood. In the present study, a team of neuroscientists from the Institute of Cognitive Neuroscience and the Bergen fMRI Group, Norway, used a combined fMRI and tract-based spatial statistics approach to investigate this question. Tract-based spatial statistics revealed several leftward asymmetric clusters in the arcuate fasciculus and uncinate fasciculus that were differentially related to functional language asymmetries. These findings suggest that white matter asymmetries may indeed be one of the factors underlying functional hemispheric asymmetries.
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Menstrual cycle affects multisensory integration
Evidence suggests that unimodal spatial processing changes across time in naturally cycling women, which is likely due to neuromodulatory effects of steroid hormones. Yet, it is unknown whether crossmodal spatial processes depend on steroid hormones as well. In the present study, a team of scientists from the Biopsychology lab, the department of Biological Psychology and Neuropsychology, University of Hamburg, and the Department of Internal and Integrative Medicine, University of Duisburg-Essen investigated this question by assessing visuo-tactile interactions in naturally cycling women, women using hormonal contraceptives and men. It was tested whether a postural effect of hand crossing on multisensory interactions in the crossmodal congruency task is modulated by women's cycle phase. It was found that visuotactile interactions changed according to cycle phase. Naturally cycling women showed a significant difference between the menstrual and the luteal phase for crossed, but not for uncrossed hands postures. The two control groups showed no test sessions effects. Regression analysis revealed a positive relation between estradiol levels and the size of crossmodal congruency effects, indicating that estradiol seems to have a neuromodulatory effect on posture processing.
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Comparable behavioral asymmetries can be based on different neuronal lateralization patterns
Pigeons and chickens display an asymmetry of their visual system which closely reassembles each other in behavior but not on anatomical level. While pigeons show an asymmetrically organized tectofugal system, only transient lateralizations of the thalamofugal system have been observed in chickens. By using neuronal tracing, scientists from the Biopsychology lab now analyzed if the thalamofugal system in adult, post hatch and dark incubated/monocular deprived pigeons show a comparable lateralization pattern to chickens. In all three conditions this was not the case. This indicates that visual lateralization in pigeons and chickens depends on tectofugal and thalamofugal asymmetries, respectively. Thus, in different species a highly similar pattern of behavioral asymmetries can be subserved by diverse neural systems.
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New insights into the genetics of language lateralization
Left-hemispheric language dominance is a well-known characteristic of the human language system, but the molecular mechanisms underlying this crucial feature of vocal communication are still far from being understood. In the present study, a team of scientist from the Department of Human Genetics and the Institute of Cognitive Neuroscience investigated effects of genetic variation in FOXP2 on individual language dominance. Two FOXP2 SNPs (rs2396753 and rs12533005) were found to be significantly associated with language lateralization. These results show that variation in FOXP2 may contribute to the inter-individual variability in hemispheric asymmetries for speech perception and thus provide an interesting insight into the molecular determinants of the asymmetric brain.
Ocklenburg, S., Arning, L., Gerding, W.M., Epplen, J.T., Güntürkün, O., Beste, C. (2013). FOXP2 variation modulates functional hemispheric asymmetries for speech perception. Brain and Language, 126, 279-284.
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Previous studies from the Biopsychology lab in Bochum had shown that right head-turning preference could represent a developmental default that might influence the development of other lateralized behaviors - such as handedness - as a consequence of orienting vision towards the right side of the body. To document the role of visual experience in promoting lateralized functions, Biopsychologists from Hamburg and Bochum now assessed head-turning preference during kissing and handedness in a group of congenitally blind human adults. They found a left-side preference for head turning but a clear right-handedness in the same individuals. This unexpected asymmetric relationship has two important implications: First, the fact that absence of developmental visual experience alters the typical right head-turning pattern suggests that this motor bias is greatly affected by sensory input. Second, the study shows that visual deprivation only alters head-turn but leaves other asymmetries like handedness unaffected). The fact that experience only selectively shapes the direction of some functional asymmetries suggests that different kinds of left-right biases are organized differently. Finally it remains to be explained why blindness leads to a reversal of head-turning asymmetry. Presently only speculations can be offered. A hint to what could possibly influence such reversal comes from observation of common patterns of behavior in most blind individuals. Blind individuals tend to keep their cane in their dominant (mostly right) hand, while holding the upper right arm or the right shoulder of their guide with their left hand, so that the interlocutor is kept on the left side. Indeed, all participants of the present study used a cane daily and reported keeping it in their right hand. This particular behavior could foster selective orienting and head turning towards the left side.
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MARLIES PINNOW IS ELECTED AS MEMBER OF THE SSM COUNCIL
The Society for the Study of Motivation (SSM) is an international, interdisciplinary organization of researchers who focus on motivation. Its mission is to encourage inquiry about all aspects of motivation from a variety of disciplines and perspectives, and to facilitate the dissemination of findings to a broad academic audience. The Society for the Study of Motivation (SSM) provides a forum for the exchange of scientific information, foster discussion of new ideas and findings on motivation among researchers, and encourages exchange and collaboration. Marlies Pinnow has now been elected as treasurer for the next period beginning in spring 2014. “It is a great honour to be a member of the SSM council and to be responsible for its financial fundament which supports all scientific, political and applied activities.” – Marlies Pinnow.
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Onur Güntürkün is elected as Member of the DFG Senate
The Senate is the statutory body of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG,) responsible for science policy. It attends to matters of general concern in research, promotes cooperation in science, advises government, parliaments and public authorities by issuing scientifically founded statements and promotes the interests of German research in relation to international science and the humanities. The Senate of the DFG has 39 members from the scientific and academic communities of which 36 are elected by the General Assembly for three-year terms. Onur Güntürkün was now elected for the period beginning with fall 2013. It is a great honor to be a member of the DFG senate. But this honor comes with the outstanding responsibility to decide on matters that deeply affect all aspects of science in Germany.
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The Connectome of the Pigeon Telencephalon
Many species of birds, including pigeons, possess demonstrable cognitive capacities, and some are even capable of cognitive feats matching those of apes. Since mammalian cortex is laminar while the avian telencephalon is nucleated, it is natural to ask whether the brains of these two cognitively capable taxa, despite their anatomical dissimilarities, might exhibit common principles of organisation on a deeper level. To find an answer to this question, a group of neuroanatomists and roboticists from Bochum, London, Auckland, Bowling Green, and Tampa came together to create the first large-scale "wiring diagram" for the forebrain of a bird. Using graph theory, they showed that, similar to mammals, the pigeon telencephalon is a modular, small-world network with a connective core of five inter-connected hub nodes that includes prefrontal-like and hippocampal structures. These regions are the most topologically central and most richly connected to the rest of the forebrain and thus central to information flow in the pigeon brain. Overall, their analysis suggests that indeed, despite the absence of cortical layers and close to 300 million years of separate evolution, the avian brain conforms to the same organisational principles as the mammalian brain on a topological level.
Shanahan, M., Bingman, V., Shimizu, T., Wild, M., Güntürkün, O. (2013). The large-scale network organization of the avian forebrain: A connectivity matrix and theoretical analysis. Frontiers in Comp. Neurosci., 7, 89.
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New Insights into Handedness Genetics
Handedness is the most obvious manifestation of cerebral lateralization in humans, but the molecular mechanisms that underlie its ontogenetic establishment are still poorly understood. In the present study a team of scientist from the Department of Human Genetics and the Institute of Cognitive Neuroscience performed an association study of LRRTM1 rs6733871 and a number of polymorphisms in PCSK6 and different aspects of handedness assessed with the Edinburgh handedness inventory in a sample of unrelated healthy adults (n=1113). PCSK6 rs10523972 SNP showed a significant association with a handedness category comparison and degree of handedness. These results provide further evidence for the role of PCSK6 as candidate for involvement in the biological mechanisms that underlie the establishment of handedness and support the assumption that degree of handedness, instead of direction, may be a more appropriate indicator of cerebral organization.
Arning, L., Ocklenburg, S., Schulz, S., Ness, V., Gerding, W.M., Hengstler, J.G., Falkenstein, M., Epplen, J.T., Güntürkün, O., Beste, C. (2013). PCSK6 VNTR Polymorphism Is Associated with Degree of Handedness but Not Direction of Handedness. PLoS ONE, 8(6), e67251.
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Quantitative Assessment of Chronic Thalamic Stroke
To a good extent the assessment of brain lesions in neuropsychological studies is still in its dark ages. Structural MRI-data are often grouped into arbitrary anatomical groups and are rarely analyzed with proper quantitative means that then can be correlated with assessments of cognitive decline. This problem is especially visible when it comes to thalamic lesions, where sometimes scientists lump most or at least major parts of the thalamus into a single basket. On the contrary, in animal research scientists have developed sophisticated techniques to quantify lesion loss for each and every anatomically identifiable nucleus. To overcome this problem, scientists from neuro- and biopsychology in Bochum teamed up and developed a procedure for a quantitative assessment of thalamic lesions in the chronic phase of an ischemic episode. The structural MR-images of 19 patients with ischemia in the thalamus were assessed by radiologic inspection. An independent rater allocated the damage to the each of the relevant thalamic nuclei. The assessments showed 89% accordance with the radiologic inspection. This procedure ranks the extent of the damage to thalamic nuclei and accounts for postacute rearrangement of the neural tissue. It will hopefully enable improved analyses in future studies that investigate cognitive effects of brain damages in patients.
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Doctoral Thesis – Vanessa Ness
On June the 14th Vanessa Ness, member of the Emmy Noether Research group, successfully defended her PhD thesis with title „A Cognitive-neurophysiological analysis of response inhibition and action chaining“. Vanessa delivered an impressive talk about a number of high-quality studies providing an in-depth analysis of the neurophysiological mechanisms underlying complex action control. The committee was impressed by the breadth of her studies and the way Vanessa defended her results.
Congratulations Vanessa !!!
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Inaugural Lecture of Christian Beste
On the 5th of June 2013 Christian Beste gave his inaugural lecture on "Cognitive Neurophysiology of Action Control: Between Basic and Applied Science". It was a fantastic tour de force of neuroscientific experiments that proceeded all the way from cells to patients. With this lecture the process of habilitation is now officially completed.
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Marsilius Medal for Onur Güntürkün
The Marsilius Lectures are activities for the academic community of all disciplines as well as for the broader public. Once a semester, the Marsilius Kolleg invites a well-known scientist to speak about a topic that calls for bridging the gaps between scholarly cultures. In recognition of their achievements in the dialogue between scholarly cultures, the speakers of the Marsilius Lecture are decorated with the Marsilius Medal. This May it was Onur’s turn. In a stunningly baroque and huge lecture hall he spoke about “Die Evolution des Denkens”. Afterwards he was awarded with the Marsilius Medal.
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Cortical Excitability does not Predict Learning and Improvisation of Complex Motor Tasks
The excitability of our cortex varies between individual and over time. Does this variability affect learning speed and even behavioral variability? Indeed, facilitation of motor cortical excitability has been shown to be positively correlated with improvements in performance in simple motor tasks. Thus cortical excitability may tentatively be considered as a marker of learning and use-dependent plasticity. Previous studies focused on changes in cortical excitability brought about by learning processes, however, the relation between native levels of cortical excitability on the one hand and brain activation and behavioral parameters on the other is as yet unknown. A team of Neurologists and Biopsychologists from Bochum now investigated the role of differential native motor cortical excitability for learning a motor sequencing task. The motor task required the participants to reproduce and improvise over a pre-learned piano sequence. Over both task conditions, participants with low cortical excitability showed significantly higher BOLD activation in task-relevant brain regions than participants with high cortical excitability. In contrast, both groups did not exhibit differences in learned performance and improvisation level. Moreover, cortical excitability did practically not change after learning and training in either group. The present data suggest that the native, unmanipulated level of cortical excitability is related to brain activation intensity, but not to performance quality. Possibly, the subjects with the lower cortical excitability possibly only showed a higher BOLD signal intensity to compensate for their lower level of excitation.
Lissek, S., Vallana, G.S., Güntürkün, O., Dinse, H., Tegenthoff, M. (2013). Brain Activation in Motor Sequence Learning Is Related to the Level of Native Cortical Excitability. PLoS ONE, 8(4), e61863.
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Learning without training
It sounds like an old dream is becoming true. Recent work suggests that intensive training may not be necessary for skill learning. Skills can be effectively acquired by a complementary approach in which the learning occurs in response to mere exposure to repetitive sensory stimulation. Such training-independent sensory learning induces lasting changes in perception and goal directed behaviour in humans, without any explicit task training. We suggest that the effectiveness of this form of learning in different sensory domains stems from the fact that the stimulation protocols used are optimized to alter synaptic transmission and efficacy. While this approach directly links behavioural research in humans with studies on cellular plasticity, other approaches show that learning can occur even in the absence of an actual stimulus. These include learning through imagery or feedback-induced cortical activation, resulting in learning without task training. All these approaches challenge our understanding of the mechanisms that mediate learning. Apparently, humans can learn under conditions thought to be impossible a few years ago. Although the underlying mechanisms are far from being understood, training-independent sensory learning opens novel possibilities for applications aimed at augmenting human cognition.
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AS GOOD AS IT GETS: PIGEONS USE A NON-OPTIMAL CHOICE STRATEGY TO ADAPT BEHAVIOR
A vast body of data supports the notion that animals, including humans, perform statistically optimally in a wide range of tasks, supporting the claim that evolution has shaped the nervous system of organisms in a way that yields maximally adaptive behavior. Optimality is frequently assessed by comparing behavioral output to benchmarks computed via methods derived from statistical decision theory. Such methods have also been used to assess the reliability of sensory neural signals, and have even been invoked as accounts of neural processing. Scientists from the Biopsychology lab have explicitly tested the claim of optimality with pigeons performing a perceptual choice task with varying reward probabilities. Surprisingly, the pattern of choices observed was opposite to that expected under an optimization account. This finding poses important constraints on the class of algorithms useful for modeling adaptive choice behavior. Furthermore, the algorithm which fit the data best was learning exclusively on correct trials ending in reward, as opposed to algorithms learning from both reward and errors. Put simply, the pigeons seem to learn from reward, but not from errors - at least when performing a psychophysical task.
Stüttgen, M.C., Kasties, N., Lengersdorf, D., Starosta, S., Güntürkün, O., Jäkel, F. (2013). Suboptimal criterion setting in a perceptual choice task with asymmetric reinforcement. Behavioural Processes, 96, 59-70.
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Putting research on cognitive control to applied clinical research
In several neurodegenerative diseases, like Huntington's disease (HD), treatments are still lacking. To determine whether a treatment is effective, sensitive disease progression biomarkers are especially needed for the premanifest phase, since this allows the evaluation of neuroprotective treatments preventing, or delaying disease manifestation. On the basis of a longitudinal study we present a biomarker that was derived by integrating behavioural and neurophysiological data reflecting cognitive processes of action control. The measure identified is sensitive enough to track disease progression over a period of only 6 month. Changes tracked were predictive for a number of clinically relevant parameters and the sensitivity of the measure was higher than that of currently used parameters to track prodromal disease progression. The study provides a biomarker, which could change practice of progression diagnostics in a major basal ganglia disease and which may help to evaluate potential neuroprotective treatments in future clinical trials.
Beste, C., Stock, A.-K., Ness, V., Hoffmann, R., Lukas, C., Saft, C. (2013). A novel cognitive-neurophysiological state biomarker in premanifest Huntington's disease validated on longitudinal data. Sci. Rep., 3, 1797.
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Proprioception – a neglected modulator of response control processes
It is well-kown that sensory information influences the way we execute motor responses. However, less is known about if and how sensory and motor information are integrated in the subsequent process of response evaluation. We used a modified Simon Task to investigate how these streams of information are integrated in response evaluation processes, applying an in-depth neurophysiological analysis of event-related potentials (ERPs), time-frequency decomposition and sLORETA. The results show that response evaluation processes are differentially modulated by afferent proprioceptive information and efference copies. While the influence of proprioceptive information is mediated via oscillations in different frequency bands, efference copy based information about the motor execution is specifically mediated via oscillations in the theta frequency band. Stages of visual perception and attention were not modulated by the interaction of proprioception and motor efference copies. Brain areas modulated by the interactive effects of proprioceptive and efference copy based information included the middle frontal gyrus and the supplementary motor area (SMA), suggesting that these areas integrate sensory information for the purpose of response evaluation. The results show how motor response evaluation processes are modulated by information about both the execution and the location of a response.
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Interpersonal Trust Varies with Menstrual Cycle
Can you trust this man? What sounds like an everyday question, is indeed a classic problem of human evolution, especially as seen from a female perspective. According to evolutionary theories, women should have different levels of trust dependent on their actual menstrual cycle. This prediction was tested by Biological Psychologists and Psychiatrists from Bochum University. They tested how trusting behavior varies in naturally cycling women, as a function of sex and attractiveness of players in a trust game, at three distinct phases of the menstrual cycle. Women acted more cautiously in an investment game at the preovulatory phase, compared to the menstrual and the mid-luteal phase. Reduced willingness to trust in strangers was particularly expressed toward male players at this time. The increase of estradiol levels from menses to the preovulatory phase was negatively correlated with trust in attractive male other players, whereas the increase of progesterone levels from menses to the mid-luteal phase was positively associated with trust in unattractive female other players. Thus, the results emphasize the impact of the menstrual cycle on interpersonal trust, although the exact mode of hormonal action needs to be further investigated.
Ball, A., Wolf, C.S., Ocklenburg, S., Herrmann, B.L., Pinnow, M., Brüne, M., Wolf, O.T., Güntürkün, O. (2013). Variability in ratings of trustworthiness across the menstrual cycle. Biol. Psychol., 93, 52-57.
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Am I a "multitasker"?
Our daily life is characterized by multiple response options that need to be cascaded in order to avoid overstrain of restricted response selection resources. While response selection and goal activation in action cascading are likely driven by a process varying from serial to parallel processing, little is known about the underlying neural mechanisms that may underlie interindividual differences in these modes of response selection. To investigate these mechanisms, we used a stop–change paradigm for the recording of event-related potentials and standardized low resolution brain electromagnetic tomography source localizations in healthy subjects. Systematically varying the stimulus onset asynchrony (the temporal spacing of “stop” and “change” signals), we applied mathematical constraints to classify subjects in more parallel or more serial goal activators during action cascading. On that basis, the electrophysiological data show that processes linking stimulus processing and response execution, but not attentional processes, underlie interindividual differences in either serial or parallel response selection modes during action cascading. On a systems level, these processes were mediated via a distributed fronto-parietal network, including the anterior cingulate cortex (Brodman area 32, BA32) and the temporo-parietal junction (BA40). There was a linear relation between the individual degree of overlap in activated task goals and electrophysiological processes.
Mückschel, M., Stock., A.-K., Beste, C. (2013). Psychophysiological mechanisms of interindividual differences in goal activation modes during action cascading. Cerebral Cortex, doi: 10.1093/cercor/bht066.
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First South-Africa-German Summer school on comparative psychology
During the last week, the "First South-Africa-German Summer school on comparative psychology" took place in one of the most exciting cities of the southern hemisphere: Johannesburg. Supported by the National Research Foundation of South Africa and the BMBF, students, young academics and senior scientist from the biopsychology lab and the department of anatomical science of the University of Witwatersrand had the opportunity to discuss their projects, plan new experiments and intensify South African -- German cooperation in the field of neuroscience. From damaraland mole rat courtship behavior over elephant hippocampus research to cetacean neuroanatomy and many other research areas the school covered a wide range of fascinating topics within the comparative psychology of unusual African model species. Receiving overwhelming positive feedback from all participants we agree that this summer school was a great experience and we are looking forward to further cooperations and activities with our old and new friends from South Africa.
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Stimulus-Response-Outcome Coding in the Pigeon Nidopallium Caudolaterale
It is important to know which events in our environment are predictive of reward or punishment. For example, knowing that the sound of the doorbell signals postal delivery while the sound of the fire alarm requires leaving the house both inform us about the present state of our world as well as about appropriate actions to take. This ability to decide on a course of action given the current state of the world is implemented in a widely distributed neural network, and one suspected hot spot for decision making is the pigeon nidopallium caudolaterale (NCL).
In the present study, neurophysiologists from the biopsychology lab recorded single-unit activity in this forebrain area while animals were working on a visual discrimination task where responding or non-responding could lead to reward, punishment, or be inconsequential. A sophisticated analysis of the NCL neurons’ activation patterns revealed that these neurons represent information about the reward value of specific stimuli, instrumental actions as well as action outcomes, and therefore provide signals useful for adaptive behavior in dynamically changing environments.
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Identification of two forebrain structures that mediate execution of memorized sequences in the pigeon
Most of our everyday activities consist of action sequences as for instance brushing your teeth, shoe lacing or driving a car. The pigeon is a classic animal model for studying the fundaments of sequence learning and execution. Yet, little is known about the neural basis mediating sequences in pigeons. In a recent study, scientists from the Biopsychology department in collaboration with the Mercator Research Group "Structure and Memory" identified two forebrain structures in the pigeon brain that play a pivotal role in mediating a memorized sequence.
Researchers of the Biopsychology department already showed in a previous study (Helduser & Güntürkün, 2012) that the nidopallium caudolaterale (NCL) and the nidopallium intermedium medilalis pars laterale (NIML) are associated with sequence execution. However, in the previous study the pigeons' behavior was cue guided. To clarify the role of both structures for memorized sequences, the authors of the recent study applied a purely memory based task. Pigeons learned to peck a four item-sequence on a touch screen. Pharmacological inactivation both of NCL and NIML impaired sequence execution confirming previous results that NCL and NIML store and process sequences in parallel. In addition, a special role of NCL for sequence initiation was revealed.
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Relating action control, anxiety and genetics
Action control mechanisms are modulated by a number of factors related to neurobiology and affective states like anxiety. However, the precise interrelation of these factors is widely unknown. The neuropeptide S (NPS) system has been suggested to contribute to the pathogenesis of anxiety. In order to further characterize the cognitive-neurophysiological relevance of neuropeptide S in the etiology of anxiety, the influence of a functional neuropeptide S receptor gene (NPSR1) variant on response inhibition and error monitoring was investigated under consideration of the dimensional phenotype of anxiety sensitivity (AS). In a sample of healthy probands, event-related potential (ERP) measurement using a modified Flanker task was applied allowing for a distinct neurophysiological examination of processes related to response inhibition and error monitoring. All subjects were genotyped for the functional NPSR1 A/T (Asn107Ile) variant (rs324981) and characterized for anxiety sensitivity using the Anxiety Sensitivity Index (ASI). Carriers of the NPSR1 T allele displayed intensified response inhibition and error monitoring, which was in both cases paralleled by the behavioral data. Furthermore, anxiety sensitivity was found to be higher in NPSR1 T allele carriers and to correlate with Nogo-P3 and Ne/ERN. A mediation analysis revealed the ERN to mediate the effect between NPSR1 genotype and anxiety sensitivity. In summary, the more active NPSR1 T allele may confer enhanced response inhibition and increased error monitoring and might drive particularly error monitoring as a neurophysiological endophenotype of anxiety as reflected by increased anxiety sensitivity. The study is among the first which is able to directly integrate mechanisms underlying action control with factors of 'anxiety' and 'genetics' into a common framework.
Beste, C., Konrad, C., Uhlmann, C., Arolt, V., Zwanzger, P., Domschke, K. (2013). Neuropeptide S receptor (NPSR1) gene variation modulates response inhibition and error monitoring. NeuroImage, 71, 1-9.
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Cholecystokinin A receptor (CCKAR) gene variation is associated with language lateralization
Language lateralization is a key feature of human brain organization, but the molecular mechanisms underlying its ontogenesis are still poorly understood. In the present study a team of scientist from the Department of Human Genetics and the Institute of Cognitive Neuroscience investigated whether variation in schizophrenia-related genes modulates individual lateralization patterns. For the first time, a significant association of genetic variation in the cholecystokinin-A receptor (CCKAR) and language lateralization was found. Individuals carrying the schizophrenia risk allele C of this polymorphism showed a marked reduction of the typical left-hemispheric dominance for language processing. Since the cholecystokinin A receptor is involved in dopamine release in the central nervous system, these findings suggest that genetic variation in this receptor may modulate language lateralization due to its impact on dopaminergic pathways.
Ocklenburg, S., Arning, L., Gerding, W.M., Epplen, J.T., Güntürkün, O. et al. (2013). Cholecystokinin A Receptor (CCKAR) Gene Variation Is Associated with Language Lateralization. PLoS ONE 8(1): e53643.
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Onur Güntürkün is now Speaker of the Research Department of Neuroscience
On the 18th of December 2012 Denise Manahan-Vaughan stepped down from as speaker of the Research Department of Neuroscience. During her term of office, the Research Department was founded and an excellent infrastructure of jointly used research facilities was established. Now as her term was over, Onur Güntürkün was elected anonymously. The elected Vice speakers are Stefan Herlitze and Ulf Eysel. The following term has its own challenges: Money is much more limited than it was before and major collaborative research grants await renewal. The picture shows Denise Manahan-Vaughan and Onur Güntürkün after the elections.
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Striatal dopamine D1 receptors are involved in the dissociation of learning based on reward-magnitude
We quickly learn that some of our actions result in reward. But reward comes in different magnitudes and we should be able to repeat those behaviors that are associated with the highest amount of reinforcement. In a new study, Biopsychologists from Boston, Oxford, and Bochum investigated the contribution of striatal dopamine receptors (D1) on the learning of reward-magnitude. To this end, pigeons were trained on a discrimination-task with two pairs of stimuli; correct discrimination resulted in a large reward in one pair of stimuli and in a small reward in the other pair. Acquisition of the discrimination-task was accompanied by intracranial injections to the medial striatum, either of a dopamine-antagonist (Sch23390) or of vehicle. In the control-condition the rate of learning was modulated by the magnitude of the reward. Following injections of D1 antagonist this effect vanished even though the ability to discriminate between the rewards was unaffected. Interestingly, the mean rate of learning was indistinguishable between the control and antagonist conditions. Consequently, it appears that not learning per se but the effect of reward-magnitude on learning is mediated through D1 receptors in the striatum. The intriguing possibility is this: It is conceivable that the injections of the dopamine-antagonist caused a shift in learning strategy. In the control-condition animals possibly relied on positive feedback and thus their learning was affected by the magnitude of the contingent reward; in the antagonist-condition, however, learning might have relied on negative feedback and was thus insensitive to reward-magnitude.
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Onur Güntürkün becomes a member of the Editorial Board of Brain, Behavior and Evolution
Onur Güntürkün accepted the invitation to become a member of the Editorial Board of Brain, Behavior and Evolution (Karger). Birds are meanwhile a key taxonomic group to understand the evolution of brain and behavior in vertebrates. And in this endeavor, the analysis of cognition gains importance. These were the reasons why Georg Striedter, the Editor-in-Chief of Brain, Behavior and Evolution invited Onur Güntürkün to come onboard to help steering this journal.
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Lateralisation of conspecific vocalisation in non-human vertebrates
Lateralization of conspecific vocalization has been observed in several vertebrate species but a systematic integration of these results across orders was lacking so far. Biopsychologists from Bochum now used cladographic comparisons to identify those vertebrate orders in which evidence for or against lateralization of conspecific vocalization has been reported, and those orders in which further research is necessary. The analysis showed that there is evidence for lateralization of conspecific vocalization in several mammalian orders (e.g. Primates) and also evidence for lateralization of conspecific vocalization in some avian species (e.g. within the Passeriformes order). While especially the primate data suggest that human language lateralization could have resulted from an inherited dominance of the left hemisphere for those neural properties of language that are shared with the sensory or motor aspects of vocalizations in other vertebrate species, it becomes clear that this conclusion presently is supported by only sparse empirical evidence. The majority of vertebrate orders, especially among non-amniotes, still need to be explored.
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Attentional distraction in aging – a role of BDNF
Aging affects the ability to focus attention on a given task and to ignore distractors. These functions subserve response control processes for which fronto-striatal networks have been shown to play an important role. Processing efficacy in these networks crucially depends upon BDNF. We investigated how cognitive subprocesses constituting a cycle of distraction, orientation and refocusing of attention are affected by the functional BDNF Val66Met polymorphism using event-related potentials (ERPs) in healthy elderly. We found that the Val/Val genotype confers a disadvantage to its carriers. This disadvantage was partly compensated by intensified attentional shifting mechanisms. It could be based on response selection processes being more vulnerable against interference from distractors in this genotype group. Processes reflecting transient sensory memory processes, or the re-orientation of attention were not affected by the BDNF Val66Met polymorphism, suggesting a higher importance of BDNF for mechanisms related to response control, than stimulus processing. The results add on recent literature showing that the Met allele confers some benefit to its carriers. We suggest an account for unifying different results of BDNF Val66Met association studies in executive functions, based on the role of BDNF in fronto-striatal circuits.
Getzmann, S., Gajewski, P.D., Hengstler, J.G., Falkenstein, M., Beste, C. (2013). BDNF Val66Met polymorphism and goal-directed behavior in healthy elderly — evidence from auditory distraction. NeuroImage, 64, 290-298.
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An MRI-based 3D digital atlas of the pigeon brain
Pigeons are classic animal models for learning, memory, and cognition. The majority of the current understanding about avian neurobiology outside of the domain of the song system has been established using pigeons. Since MRI represents an increasingly relevant tool for comparative neuroscience, a 3-dimensional MRI-based atlas of the pigeon brain becomes essential. Using multiple imaging protocols, a team from the Biopsychology in Bochum and the Bioimaging Centre in Antwerp delineated diverse ascending sensory and descending motor systems as well as the hippocampal formation. The resulting pigeon brain atlas can easily be used to determine the stereotactic location of identified neural structures at any angle of the head. The atlas is freely available for the scientific community. Just click on the button with the scan of the pigeon head to the left of this text.
Güntürkün, O., Verhoye, M., De Groof, G., Van der Linden, A. (2013). A 3-dimensional digital atlas of the ascending sensory and the descending motor systems in the pigeon brain. Brain Structure Function, 218, 269-281.
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Onur Güntürkün is accepted as a fellow of the Wissenschaftskolleg zu Berlin
Running a big university lab is like continuously juggling a dozen balls. Every moment multiple tasks have to performed, projects that unfold in timescales of days to years have to be monitored, kilograms of papers have to reviewed and produced, and, finally, literature has to be read, understood and integrated into an ever-growing tapestry of knowledge. At the same time, competition is tough and reputation that has been built in decades can be destroyed in a day. There simply is no time to deeply think about issues that need weeks to grow in your mind.
Therefore Onur Güntürkün accepted the invitation to apply for a stay in the Wissenschaftskolleg zu Berlin (WiKo). There, in Berlin Grunewald, scientists can move into apartments within a classic villa and just think deeply for up to one year, while WiKo pays their salary to the home university for teaching replacement. Now, WiKo accepted him a fellow. The plan is not to stay for full 12 months but to take a stay from October 2014 to April 2015.
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Functional MRI and functional connectivity of the visual system of awake pigeons
Functional MRI (fMRI) is widespread in humans but still rare in animal research. If being applied, nearly always anaesthetized animals are used. Only a few articles present results obtained in awake rodents. With advent of the "cognitive bird revolution", awake bird fMRI is increasingly relevant. Bioimaging experts from Antwerp and Biopsychologists from Bochum now conducted the first awake bird imaging study with highly habituated and head fixed pigeons. Both traditional fMRI and resting state (rsfMRI) were applied. In addition, this is the first time functional connectivity measurements were performed in a non-mammalian species. Since the visual system of pigeons is a well-known model for brain asymmetry, the focus of the study was on the neural substrate of the visual system. For fMRI a visual stimulus was used and functional connectivity measurements were done with the entopallium as a seed region. Interestingly in awake pigeons the left E was significantly functionally connected to the right E. Moreover connectivity maps for a seed region in both hemispheres resulted in a stronger bilateral connectivity starting from left E. These results could be used as a starting point for further imaging studies in awake birds and also provide a new window into the analysis of hemispheric dominance in the pigeon.
De Groof, G., Jonckers, E., Güntürkün, O., Denolf, P., Auderkerke, J.V., Van der Linden, A. (2013). Functional MRI and functional connectivity of the visual system of awake pigeons. Behavioural Brain Research, 239, 43-50.
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Oxytocin Modulates Social Distance between Males and Females
In humans, interpersonal romantic attraction and the subsequent development of monogamous pair-bonds is substantially predicted by influential impressions formed during first encounters. The prosocial neuropeptide oxytocin (OXT) has been identified as a key facilitator of both interpersonal attraction and the formation of parental attachment. However, whether OXT contributes to the maintenance of monogamous bonds after they have been formed is unclear. Psychiatrists from Bonn, Biopsychologists from Bochum and Neuroscientists from Chengdu now provide the first behavioral evidence that the intranasal administration of OXT stimulates men in a monogamous relationship, but not single ones, to keep a much greater distance (10 –15 cm) between themselves and an attractive woman during a first encounter. They further confirmed this using a photograph-based approach/avoidance task that showed again that OXT only stimulated men in a monogamous relationship to approach pictures of attractive women more slowly. Importantly, these changes cannot be attributed to OXT altering the attitude of monogamous men toward attractive women or their judgments of and arousal by pictures of them. Together, these results suggest that where OXT release is stimulated during a monogamous relationship, it may additionally promote its maintenance by making men avoid signaling romantic interest to other women through close-approach behavior during social encounters. In this way, OXT may help to promote fidelity within monogamous human relationships.
Scheele, D., Striepens, N., Güntürkün, O., Deutschländer, S., Maier, W., Kendrick, K.M., Hurlemann, R. (2012). Oxytocin modulates social distance between males and females. J. Neurosci., 32, 16074-16079.
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Onur Güntürkün receives Gottfried Wilhelm Leibniz Award
On the 6th of December 2012 The Senate of the Deutsche Forschungsgemeinschaft decided to award Onur Güntürkün with the Gottfried Wilhelm Leibniz Award. With 2.5 million Euro that can freely be spent within 7 years, the Leibniz award is the highest European award of its kind. The DFG calls it "freedom like in fairy tales".
It feels like that.
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Doctoral Thesis – Sascha Helduser
Sascha Helduser successfully graduated on the 5th of December 2012 and was awarded with a PhD of Neuroscience. Sascha was able to achieve major insights into the neural basis of sequence learning and sequential behavior in pigeons. Given that many insights into the behavioral fundaments of sequencing were gained by studying pigeons, it was amazing that practically nothing was known about the brain systems that mediate this type of behavior. By training pigeons in various complex behavioral studies and subsequently blocking the activity of different brain areas, Sascha was able reveal that two brain structures were especially relevant. One was the NCL, the bird equivalent of the prefrontal cortex. The other was the pallial component of a "cortico"-basal ganglia-thalamus loop. The name of this structure in song birds is LMAN (please have a look at his t-shirt!). Both of these two structures contribute to sequential behavior, albeit slightly differently. In his final experiment Sascha was even able to increase the success of sequence execution by microstimulating the NCL shortly before sequence onset. The committee was truly impressed with Sascha's achievements and decided to award him the doctorate title with the grade magna cum laude.
CONGRATULATIONS SASCHA !!!
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New Biopsychology Doctor
On Tuesday the 27th Stefanie Schulz received her PhD (Dr. rer. nat.) for her work on neurogenetic foundations of attentional processes. In her studies she examined the role of various single nucleotide polymorphisms for attentional processes within the framework of the attention network test. Already her written thesis was impressive. In a marvelous defense of her work she impressed the committee with her in-depth knowledge on attentional processes and neurobiological foundations thereof. It was a great having you in the Biopsychology, Motivational Psychology and Emmy Noether Group team.
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Tagrid Yousef Receives German Teacher Award
Since several years Tagrid is giving the Neurophysiology lecture on behalf of the chair of Biopsychology. Since then our students start with a comprehensive and perfectly presented knowledge about neuronal functions into their studies. Now the outstanding pedagogical skills of Tagrid were awarded by the highest possible institution. A consortium consisting of the German Philological Society and several foundations selected just ten out of 3,500 nominated teachers for this high honor; and Tagrid was one of these few selected ones. The key issue is that teachers can't apply; their former students nominate and vote for them! Tagrid received the award for her fantastic commitment to teaching, her approachability, and her dedication to transmit the full complexity of the content in the best possible way. Tagrid shows up at dawn in the slaughterhouse to snatch a pig brain for her class and she is faced with children from a societal background as remote from academia as you can imagine. But she is standing the ground and delivers her message that science is the key to the future.
Congratulations, Tagrid !!!
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Pseudoneglect in Chronic Pain Patients
Complex regional pain syndrome (CRPS1) is a chronic progressive disease characterized by severe pain without demonstrable nerve lesion. It often affects an arm or a leg and may spread to another part of the body. In a previous study biopsychologists and neurologists from Bochum had shown that CRPS-patients have a remarkable shift of the visual subjective body midline, a correlate of the egocentric reference frame, towards the affected side (Reinersmann et al., 2010). However, this first study fell short of showing if this asymmetrical change of the egocentric computation was specific for CRPS. Now, the same team is able to report that this asymmetric subjective shift towards the left side is specific for CRPS1-patients with right sided pain and does not occur in controls or in patients with other types of chronic pain. Thus, right-affected CRPS1-patients display an asymmetrical attentional spatial focus that is thought to result from unilateral CRPS pain inducing a somatosensory imbalance, with pain providing ''exaggerated'' input from the affected side. This then could distort visuospatial perception, including perceptual representation of one's own body. This study shows that CRPS1 is a syndrome of sensory-motor-autonomic dysfunctions that goes along with neural changes that control lateralized attentional systems.
The editors of the journal thought this discovery to be of great importance and associated it with an invited commentary (Greenspan, 2012).
Reinersmann, A., Landwehrt, J., Krumova, E.K., Ocklenburg, S., Güntürkün, O., Maier, C. (2012). Impaired spatial body representation in complex regional pain syndrome type 1 (CRPS I). Pain, 153, 2174-2181.
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Numerosity in Dolphins
In a previous study biopsychologists from Bochum and Nürnberg had demonstrated that bottlenose dolphins can discriminate visual stimuli according to their numerosity (the number of objects displayed in pictures). But are dolphins able to use an abstract numerical category based on "few" vs. "many" when discriminating stimuli according to the number of their constituent patterns? And how do they mentally represent numerosity? To this end, a team of Biopsychologists from Bochum, Mallorca and Nürnberg trained Blue, an adult bottlenose dolphin, to discriminate between two simultaneously presented stimuli which varied in the number of elements they contained. After initial training, several confounding parameters were excluded to show that discrimination performance indeed depended on numerosity. Subsequently, the animal was tested with new stimuli of intermediate as well as higher numbers of elements. Once discrimination had been achieved, a reversal-training on a subset of stimuli was initiated. Afterward, the subject generalized the reversal successful to new and unreinforced stimuli. These results reveal two main findings: firstly, after reversal learning, Blue generalized the reversal successful to new and unreinforced stimuli. Thus, the results suggest that dolphins are able to learn and use a numerical category that is based on abstract qualities of "few" vs. "many." In addition, the occasional errors of Blue strongly suggest a magnitude and a distance effect. Thus, coding of numerical information in dolphins might follow logarithmic scaling as postulated by the Weber-Fechner law.
Yaman, S., Kilian, A., von Fersen, L., Güntürkün, O. (2012). Evidence for a numerosity category that is based on abstract qualities of “few” vs. “many” in the bottlenose dolphin (Tursiops truncatus). Frontiers in Psychology, 3: 473.
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Poster Prize – Vanessa Neß
Vanessa Neß participated in this year's "FoRUM" conference hosted by the medical faculty of the RUB. For her poster presentation summarizing a cooperation project with the human genetics group, funded by FoRUM (Forschungsförderung Ruhr-Universität Bochum Medizinischen Fakultät), she won a poster prize in her category endowed with a prize money of 500€. The dopaminergic system is known to modulate decision-making. With N-methyl-D-aspartate receptors (NMDARs) strongly influence dopaminergic functioning, it is conceivable that the glutamatergic system is also involved in decision-making. The GRIN2B gene codes for the NMDAR subunit 2B determining receptor affinity. Out of 15 polymorphisms of the GRIN2B gene, two showed a strong association with strategic aspects of IGT performance. The results suggest that healthy individuals with certain GRIN2B variations respond differently to ambiguous conditions, possibly by altered perception of wins and losses. These findings underline the necessity to integrate the glutamatergic system when examining decision making processes.
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Prefrontal Asymmetries of Empathy
Humans incur considerable costs to punish unfairness directed towards themselves or others. Recent studies using repetitive transcranial magnetic stimulation (rTMS) suggest that the right dorsolateral prefrontal cortex (DLPFC) is causally involved in such strategic decisions. Presently, two partly divergent hypotheses are discussed, suggesting either that the right DLPFC is necessary to control selfish motives by implementing culturally transmitted social norms, or is involved in suppressing emotion-driven prepotent responses to perceived unfairness. Accordingly, a team of psychiatrists and biopsychologists from Bochum studied the role of the DLPFC in costly (i.e. third party) punishment by applying rTMS to the left and right DLPFC before playing a Dictator Game with the option to punish observed unfair behavior (DG-P). Costly punishment increased, albeit nonsignificantly, upon disruption of the right – but not the left – DLPFC as compared to sham stimulation. However, empathy emerged as a highly significant moderator variable of the effect of rTMS over the right, but not left, DLPFC, suggesting that the right DLPFC is involved in controlling prepotent emotional responses to observed unfairness, depending on individual differences in empathy.
Brüne, M., Scheele, D., Heinisch, C., Tas, C., Wischniewski, J., Güntürkün, O. (2012). Empathy Moderates the Effect of Repetitive Transcranial Magnetic Stimulation of the Right Dorsolateral Prefrontal Cortex on Costly Punishment. PLoS ONE, 7(9): e44747.
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The new 7T-Animal Scanner Facility Opened
On the 22nd of October 2012 the new Bruker 7 Tesla animal MRT-scanner facility was opened with a nice ceremony. The system was awarded by the Mercator Foundation to the Mercator Research Group „Structure of Memory“. The facility includes, besides the scanner, a surgery and a testing room as well as animal housing facilities for mice, rats, and pigeons. In addition, a physicist from Caltech was hired to run the system. The first pictures taken were from mandarins and kiwis, but meanwhile mice, rat, and pigeon brains were also successfully analyzed. The goal for the Biopsychology lab will be to establish awake pigeon fMRI.
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Development of lateralization of the magnetic compass
Recently, a dispute on the presence or absence of asymmetry of the avian magnetic compass was discussed in Nature (Nature, 2011, 471: E12-13). A new study from biologists in Frankfurt and biopsychologists in Bochum could clarify some of the contradictions. They now revealed that the lateralized magnetic compass of the migratory European robin is not asymmetrically organized from the ontogenetic beginning, but develops as the birds grow older. During first migration in autumn, juvenile robins can orient by their magnetic compass with both eyes. In the following spring, however, the magnetic compass is already lateralized towards the right eye/left hemisphere, but this lateralization is still flexible: it could be removed by covering the right eye for 6 h. During the following autumn migration, the lateralization becomes more strongly fixed, with a 6 h occlusion of the right eye no longer having an effect. This change from a bilateral to a lateralized magnetic compass appears to be a maturation process, the first such case known so far in birds. Because both eyes mediate identical information about the geomagnetic field, brain asymmetry for the magnetic compass could increase efficiency by setting the other hemisphere free for other processes.
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Increasing learning by excitotoxic neurodegeneration
Glutamatergic neural transmission is involved in both neural plasticity and neurodegeneration. This combination of roles could result in ambivalent effects in which excitotoxic neurodegeneration augments neural plasticity in parallel. Neural plasticity can be induced by exposure-based learning (EBL) that resembles timing properties of long-term potentiation (LTP) protocols (i.e., LTP-like learning). Even though it has not been demonstrated so far in animal models that perceptual effects of such stimulation protocols are mediated by typical LTP mechanisms, it has been shown that exposure-based learning exerts strong effects on cognitive brain functioning and is modulated by glutamatergic neural transmission. We reveal that exposure-based perceptual learning is more efficient in a human model of excitotoxic neurodegeneration than in healthy participants. Pre-manifest Huntington's disease gene mutation carriers showed faster increases in perceptual sensitivities than controls. This in turn changed attentional processing in extrastriate visual areas objectified using electroencephalogram data. The emergence of faster learning correlated positively with genetic disease load. Our results confirm an ambivalent action of increased glutamatergic transmission, implying that the process of excitotoxic neurodegeneration is associated with enhanced perceptual learning, which can be used to improve attentional and behavioral control via the alteration of perceptual sensitivities.
“A thought-provoking new study has found that symptom-free carriers of the neurodegenerative Huntington’s disease present a dramatic two-fold acceleration in perceptual learning.” (Cardoso-Leite et al., 2012).
“These results are spectacular in the face of the massive literature showing subtle cognitive impairments in pre-HD patients.” (Cardoso-Leite et al., 2012).
“Adapting the exposure-based learning procedure pioneered in the present study to animal models in future research could be a productive way to characterize the respective mechanisms subtending enhanced learning and excitotoxicity in Huntington’s disease.” (Cardoso-Leite et al., 2012).
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A new View on the Role of the Thalamus for Memory Functions
The functional role of the mediodorsal thalamic nucleus (MD) and its cortical network for recognition and memory recall is discussed controversially. Neuropsychologists and Biopsychologists from Bochum now decided to take a fresh approach: They studied patients with focal thalamic lesions to examine the functions of the MD, the intralaminar nuclei and the midline nuclei in memory processing. In addition, a newly designed pair association task was used, which allowed the assessment of recognition and cued recall performance. Most importantly, volume loss in thalamic nuclei was estimated with a technique that had been invented in animal research but was used in this study for the first time on humans. These quantitative anatomical data could then be used as a predictor for alterations in memory performance. The results reveal that reduced recall of picture pairs and increased response times during recognition followed by cued recall covaried with the volume loss in the parvocellular MD. This pattern suggests a role of this thalamic region in recall and thus recollection, which does not fit into the classic framework that is in use in today's Neuropsychology. The functional specialization of the parvocellular MD accords with its connectivity to the dorsolateral PFC, highlighting the role of this thalamocortical network in explicit memory.
Pergola, G., Suchan, B., Güntürkün, O., Koch, B., Schwarz, M., Daum, I. (2012). Recall deficits in stroke patients with thalamic lesions covary with damage to the parvocellular mediodorsal nucleus of the thalamus. Neuropsychologia, 50, 2477-2491.
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Sebastian Ocklenburg is awarded with the Heinz-Heckhausen-Jungwissenschaftlerpreis
The German Psychological Society decided to award Sebastian Ocklenburg this year’s Heinz-Heckhausen Young Investigator Award for his outstanding dissertation. During the laudatio, Prof. Oliver Wolf outlined that the committee of the German Psychological Society was deeply impressed by the quality and the quantity of publications that constitute Sebastian’s thesis. Oliver Wolf then went on to say that the breadth of the studies on cerebral asymmetries conducted by Sebastian start to lay the fundaments of a theory of brain asymmetry. The Heinz-Heckhausen Young Investigator Award is only given once in two years during the Congress of the German Psychological Society.
CONGRATULATIONS SEBASTIAN !!!
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First South-African-German Summerschool on comparative psychology
Die "First South African-German summer school on comparative psychology" ist ein professionelles Fortbildungsprogramm innerhalb der vergleichenden Psychologie, einer neu aufkommenden Fachrichtung innerhalb der Geisteswissenschaften, die sich mit den evolutionären Hintergründen der menschlichen Kognition beschäftigt.
Die Summer School wird unter der Leitung von Dr. Nina Patzke und Prof. Paul Manger in Zusammenarbeit mit der Arbeitseinheit Biopsychologie, an der Universität von Witwatersrand, Johannesburg, Südafrika im Februar 2013 stattfinden und aus einer Mischung von wissenschaftlichen Vorträgen, Projektdiskussionen und dem Training von praktischen Forschungstätigkeiten bestehen.
Die Summer School findet vom 18. bis zum 22. Februar 2013 an der Universität von Witwatersrand, Johannesburg, Südafrika statt. Zielgruppe sind junge, südafrikanische Wissenschaftler innerhalb des Master- oder Promotionsstudiums, die sich für den Bereich der vergleichenden Psychologie interessieren. Bewerben können sich Wissenschaftler aus dem Feld der Geisteswissenschaften, Biologie, Psychologie oder Medizin. Wir möchten besonders junge Wissenschaftlerinnen ansprechen, da die Summer School eine spezielle Vortragsreihe mit dem Titel "women in science" (siehe Programm) enthält, in dem zwei erfolgreiche Wissenschaftlerinnen aus Deutschland und Südafrika über Ihren Werdegang, sowie Chancen und Karrieremöglichkeiten für Frauen in der Wissenschaft berichten. Es wird eine möglichst kleine Gruppengröße angestrebt um den Austausch zwischen Teilnehmern und den vortragenden Wissenschaftlern zu erleichtern und individuelle Beratungsgespräche zu ermöglichen. Daher ist die Anzahl der Teilnehmer auf 10 Bewerber begrenzt.
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Neural Correlates of Individual Performance Differences in Resolving Perceptual Conflict
Attentional mechanisms are a crucial prerequisite to organize behavior. Most situations may be characterized by a ‘competition’ between salient, but irrelevant stimuli and less salient, relevant stimuli. In such situations top-down and bottom-up mechanisms interact with each other. In the present fMRI study, we examined how interindividual differences in resolving situations of perceptual conflict are reflected in brain networks mediating attentional selection. Good performers presented increased activation in the orbitofrontal cortex (BA 11), anterior cingulate (BA 25), inferior parietal lobule (BA 40) and visual areas V2 and V3 but decreased activation in BA 39. This suggests that areas mediating top-down attentional control are stronger activated in this group. Increased activity in visual areas reflects distinct neuronal enhancement relating to selective attentional mechanisms in order to solve the perceptual conflict. Opposed to good performers, brain areas activated by poor performers comprised the left inferior parietal lobule (BA 39) and fronto-parietal and visual regions were continuously deactivated, suggesting that poor performers perceive stronger conflict than good performers. Moreover, the suppression of neural activation in visual areas might indicate a strategy of poor performers to inhibit the processing of the irrelevant non-target feature. These results indicate that high sensitivity in perceptual areas and increased attentional control led to less conflict in stimulus processing and consequently to higher performance in competitive attentional selection.
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Rubber hand illusion modulates pseudoneglect
The rubber hand illusion (RHI) refers to the illusory perception of ownership of a rubber hand that may occur when covert tactile stimulation of a participant’s hand co-occurs with overt corresponding stimulation of a rubber hand. In the current study a team of IKN scientists from the Neuro- and Biopsychology labs investigated the influence of the RHI on pseudoneglect on the line bisection task (the leftward bias when marking the centre of horizontal lines). The results of study suggest that integrating the left sided rubber hand into one’s body image shifts the subjective body midline to the right, thus counteracting pseudoneglect.
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GRIN2B gene variation associated with alerting, but not with orienting and conflicting
Appropriate attention levels are pivotal for cognitive processes, and individual differences in attentional functioning are related to variations in the interplay of neurotransmitters. In the present study, the role of variation in GRIN2B, which encodes the NR2B subunit of N-methyl-d-aspartate (NMDA) receptors, was explored.
The study focuses on the regulation of arousal and attention by comparing the efficiency of the three attention networks alerting, orienting and conflicting as measured with the Attention Network Test (ANT). Two synonymous SNPs in GRIN2B, rs1806201 (T888T) and rs1806191 (H1178H) were genotyped in 324 young Caucasian adults. Results revealed a highly specific modulatory influence of SNP rs1806201 on alerting processes with subjects homozygous for the frequent C allele displaying higher alerting network scores as compared to the other two genotype groups (CT and TT). This result can be further explained by faster reaction times in the no-cue condition of the ANT (tonic alertness) in participants carrying at least one of the rare T alleles, possibly as a result of more effective glutamatergic neurotransmission.
Schulz, S., Arning, L., Pinnow, M., Epplen, J.T., Beste, C. (2012). N-methyl-d-aspartate receptor 2B subunit (GRIN2B) gene variation is associated with alerting, but not with orienting and conflicting in the attention network test. Neuropharmacology, 63, 259-265.
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Habilitation – Christian Beste
Christian Beste successfully habilitated on the 10th of July 2012 in the Faculty of Psychology for “Cognitive Neuroscience”. His written thesis was already impressive by its coverage, depth, and publication quality. Now, he performed equally well with his oral presentation on “Effortless Learning: Fact or Fiction”. Christian could show that mere, high-frequency exposure learning can create an LTP-like process that dramatically increases the probability to detect certain stimuli. Conversely, an LTD-like training protocol decreases stimulus detection. Thus, effortless learning seems to work and thus is a fact. However, Christian also revealed that it is fiction to hope for a generalized effortless learning ability. Altogether, this was a very strong presentation and the committee unanimously decided that Christian Beste should be awarded with the habilitation of the Faculty of Psychology.
CONGRATULATIONS CHRISTIAN !!!
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The Differential Role of Dopamine Receptors on Cognitive Training
Dopamine D1-like receptors consist of D1 (D1A) and D5 (D1B) receptors and play a key role in working memory. However, their possibly differential contribution to working memory is unclear. In birds, the D1-like receptor family is extended and consists of the D1A, D1B, and D1D receptors. Their possibly differential contribution to cognitive training is mostly unclear. Biopsychologists from Bochum and Düsseldorf combined a working memory training protocol with a stepwise increase of cognitive subcomponents and real-time RT-PCR analysis of dopamine receptor expression in pigeons to identify molecular changes that accompany training of isolated cognitive subfunctions. They conducted a behavioral working memory paradigm that works like Russian Matryoshka dolls: The four tasks were designed with increasing cognitive demands such that task 2 had one cognitive component more than task 1, task 3 had more components than task 2 and so on. By subtraction of cognitive faculties between tasks, expression changes ofD1A, D1B, andD1D in striatum and avian "prefrontal cortex", could therefore be mapped to specific subcomponents of cognitive training. The data show that D1B receptor plasticity follows a training that includes active mental maintenance of information, whereas D1A and D1D receptor plasticity in addition accompanies learning of stimulus-response associations. Plasticity of D1-like receptors plays no role for processes like response selection and stimulus discrimination. None of the tasks altered D2 receptor expression. The present study shows for the first time that different cognitive components of working memory training have distinguishable effects on D1-like receptor expression.
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Doctoral Thesis – Anna Ball
Anna Ball successfully graduated on the 3rd of July 2012 and was awarded with a Dr. rer. nat in Psychology. Anna conducted a huge, highly complex and perfectly designed study in which she analyzed the alterations of hormones, brain asymmetries, psychophysical markers, social cognitive features, and motivational scores during the menstrual cycle. Anna departed in her study from an evolutionary perspective in which she proposed that cognitive changes during the menstrual cycle have to be seen as behavioral adaptations that increase the fitness of the individual. Going even a step further, she also assumed that alterations of brain asymmetries could represent the mean to achieve these behavioral changes. Anna tested three groups of subjects: normally cycling females, young female subjects that use a vaginal contraceptive ring (thereby preventing a normal cycle), and young men. In the end, she was rewarded with a large number of results that show how alterations of hormones affect various alterations of cognition, motivation, brain states, and strategic behavior. The committee was truly impressed with Anna's contributions and decided to award her the doctorate title with the grade magna cum laude.
CONGRATULATIONS ANNA !!!
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NEW MATLAB SOFTWARE PACKAGE FOR THE ANALYSIS OF SPIKE DATA
MLIB is a MATLAB-based software package for the analysis of the spike data, ie shapes and temporal patterns of extracellularly recorded action potentials. In particular, MLIB contains functions for a) assessing spike sorting quality / unit isolation, and b) constructing all sorts of peri-stimulus time histograms as well as raster displays and spike density functions constructed with various filter kernels. The software package is accompanied by an extensive documentation, along with many examples using spike data from operantly conditioned, freely moving pigeons. The software can be downloaded from Matlab Central File Exchange.
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Poster Prize – Ann-Kathrin Stock
Ann-Kathrin Stock participated in this year’s “Psychologie und Gehirn” conference of the DGPA in Jena where she presented two posters. For one of her posters dealing with the differential effects of ADORA2A gene variations in pre-attentive visual sensory memory subprocesses she won the conference’s poster prize (“Posterpreis der Fachgruppe ‘Biologische Psychologie und Neuropsychologie’ der Deutschen Gesellschaft für Psychologie (DGPs) 2012”) endowed with a prize money of 300€.
The ADORA2A gene encodes the adenosine A2A receptor which is highly expressed in the striatum where it plays a role in modulating glutamatergic and dopaminergic transmission. While knowledge about the influence of phasic dopaminergic modulation on pre-attentive sensory stimulus processing is rather well-established, less is known about glutamatergic signaling in this context. Studying two polymorphisms, it could be shown that the rare homozygous genotypes seem to be associated with differences in the efficiency of pre-attentive sensory memory sub-processes most likely modulated by dopaminergic and glutamatergic signaling in a dissociable manner.
CONGRATULATIONS ANN-KATHRIN !!!
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Multitasking and fronto-striatal circuits
Flexible response adaptation and the control of conflicting information play a pivotal role in daily life. Yet, little is known about the neuronal mechanisms mediating parallel control of these processes. We examined these mechanisms using a multi-methodological approach that integrated data from event-related potentials (ERPs) with structural MRI data and source localisation using sLORETA. Moreover, we calculated evoked wavelet oscillations. We applied this multi-methodological approach in healthy subjects and patients in a prodromal phase of a major basal ganglia disorder (i.e., Huntington's disease), to directly focus on fronto-striatal networks. Behavioural data indicated, especially the parallel execution of conflict monitoring and flexible response adaptation was modulated across the examined cohorts. When both processes do not co-incide a high integrity of fronto-striatal loops seems to be dispensable. The neurophysiological data suggests that conflict monitoring (reflected by the N2 ERP) and working memory processes (reflected by the P3 ERP) differentially contribute to this pattern of results. Flexible response adaptation under the constraint of high conflict processing affected the N2 and P3 ERP, as well as their delta frequency band oscillations. Yet, modulatory effects were strongest for the N2 ERP and evoked wavelet oscillations in this time range. The N2 ERPs were localized in the anterior cingulate cortex (BA32, BA24). Modulations of the P3 ERP were localized in parietal areas (BA7). In addition, MRI-determined caudate head volume predicted modulations in conflict monitoring, but not working memory processes. The results show how parallel conflict monitoring and flexible adaptation of action is mediated via frontostriatal networks. While both, response monitoring and working memory processes seem to play a role, especially response selection processes and ACC–basal ganglia networks seem to be the driving force in mediating parallel conflict monitoring and flexible adaptation of actions.
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It is a commonly known that attentional processes are prone to distraction. Misguidance of attention can lead to severe declines in the control of behaviour. However, several theories suggest that attention is a necessary but not sufficient prerequisite for aware perception. These mechanisms can be investigated using change detection tasks. The present study investigates the mechanisms behind such perceptual errors and their relation to error processing on higher cognitive levels. By analyzing event-related potentials in the EEG separately in those error prone conflict trials for correct and erroneous change detection, we demonstrate that only correct change detection was associated with the allocation of attention to the relevant luminance change. Erroneous change detection was associated with an initial capture of attention toward the irrelevant orientation change in the N1 time window and a lack of subsequent target selection processes (N2pc). Errors were additionally accompanied by an increase of the fronto-central N2 and a kind of error negativity (Ne or ERN), which, however, peaked prior to the response. These results suggest that a strong perceptual conflict by salient distractors can disrupt the further processing of relevant information and thus affect its aware perception. Yet, it does not impair higher cognitive processes for conflict and error detection, indicating that these processes are independent from awareness.
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NEW DFG RESEARCH GRANT FOR MAIK STÜTTGEN
It is widely held that spike responses of single neurons to sensory stimuli are noisy and uninformative. Accordingly, random fluctuations of individual neurons’ activity patterns are considered unimportant because downstream brain areas must perform some sort of averaging across large neuronal populations to obtain accurate information about sensory input variables. Contrary to this notion, recent studies have shown that electrical activation of single cortical neurons can indeed have behavioral relevance. For example, single-neuron stimulation in rat primary motor cortex generates movements of the facial whiskers. Moreover, stimulation of single neurons in somatosensory cortex yields a behavioral response in rats trained on a psychophysical detection task. These studies suggest that the influence of an individual cortical neuron on the local neural network is stronger than commonly thought. However, the mechanism by which the activity of a single neuron is amplified and propagated through the local neural network to eventually generate a behavioral response is unknown. The aim of the newly approved six-month research project is to begin to elucidate some of the mechanisms which underlie the phenomenon of single-cell induced behavioral responses. Together with Arthur Houweling at the University of Rotterdam, Maik will employ the juxtacellular stimulation technique to activate single neurons in the superficial layers of barrel cortex of anesthetized mice in a controlled manner while monitoring the activity of the local neural network.
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Lateralized Processing at the Cellular Level
In humans and many other animals, the two cerebral hemispheres are partly specialized for different functions. However, knowledge about the neuronal basis of lateralization is mostly lacking. The visual system of birds is an excellent model in which to investigate hemispheric asymmetries as birds show a pronounced left hemispheric advantage in the discrimination of various visual objects. Therefore, biopsychologists and theoretical neuroscientists from Bochum and Freiburg, respectively, aimed to find a neuronal correlate for three hallmarks of visual lateralization in pigeons: first, the animals learn faster with the right eye–left hemisphere; second, they reach higher performance levels under this condition; third, visually guided behavior is mostly under left hemisphere control. To this end, Josine Verhaal (now at the Munich Technical University) recorded from the left and right forebrain entopallium while the animals performed a colour discrimination task. Josine found that, even before learning, left entopallial neurons were more responsive to visual stimulation. Subsequent discrimination acquisition recruited more neuronal responses in the left entopallium and these cells showed a higher degree of differentiation between the rewarded and the unrewarded stimulus. Thus, differential left–right responses are already present, albeit to a modest degree, before learning. As soon as some cues are associated with reward, however, this asymmetry increases substantially and the higher discrimination ratio of the left hemispheric tectofugal pathway would not only contribute to a higher performance of this hemisphere but could thereby also result in a left hemispheric dominance over downstream motor structures via reward-associated feedback systems.
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Evolutionary Roots of Emotional Reactions
Possibly emotions are just a means to coordinate fast actions to stimuli that have a valence character. In the present study biological psychologists from Bochum and Würzburg planned to test if the left hemisphere preferentially controls flexion responses toward positive stimuli, while the right hemisphere is specialized toward extensor responses to negative pictures. To this end, right-handed subjects had to pull or push a joystick subsequent to seeing a positive or a negative stimulus in their left or right visual hemifield. Flexion responses were faster for positive stimuli (upper picture), while negative stimuli were associated with faster extensions responses (lower picture). Overall, performance was fastest when emotional stimuli were presented to the left visual hemifield. This right hemisphere superiority was especially clear for negative stimuli, while reaction times toward positive pictures showed no hemispheric difference. Thus, flexion and extension are indeed tightly linked to the valence of the stimulus. But the division of valence between hemispheres is not as clear. This fits to recent developments that an approach reaction (in this case visible as a flexion response) can be elicited by positive emotions as well as by anger, which is a negative emotion.
Önal-Hartmann, C., Pauli, P., Ocklenburg, S., Güntürkün, O. (2012). The motor side of emotions: investigating the relationship between hemispheres, motor reactions and emotional stimuli. Psychol. Res., 76, 311-316.
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Selective attention is boosted by smoking in schizophrenia
Smoking prevalence is highly elevated in schizophrenia compared to the general population and to other psychiatric populations. Evidence suggests that smoking may lead to improvements of schizophrenia-associated attention deficits; however, large-scale studies on this important issue are scarce. A group of psychiatrists from Berlin and biopsychologists from Bochum examined whether sustained, selective, and executive attention processes are differentially modulated by long-term nicotine consumption in 104 schizophrenia patients and 104 carefully matched healthy controls. Smoking was significantly associated with a detrimental conflict effect in controls, while the opposite effect was revealed for schizophrenia patients. Likewise, a positive correlation between a cumulative measure of nicotine consumption and conflict effect in controls and a negative correlation in patients were found. These results provide evidence for specific directional effects of smoking on conflict processing that critically dissociate with diagnosis. The data supports the self-medication hypothesis of smoking in schizophrenia and suggests selective attention as a specific cognitive domain positively targeted by nicotine consumption. The authors offer a model to explain the dissociating effects by nicotine-dopamine interactions located in the ventral tegmental area that lead to an increased prefrontal D1 receptor activation. As a consequence, smoking is disadvantageous for healthy participants with a priori favorable dopamine levels, but reinstates an advantageous D1 state in schizophrenia patients who otherwise suffer from a marked prefrontal dopamine deficit.
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The convergent evolution of neural substrates for cognition
This review by Onur Güntürkün describes a case of convergence in the evolution of brain and cognition. Both mammals and birds can organize their behavior flexibly over time and evolved similar cognitive skills. However, mammals and birds display vast differences in the organization of their forebrains with mammals having a laminated cortex. The avian forebrain displays no such lamination; hence, lamination does not seem to be a requirement for higher cognitive functions. In mammals, executive functions are associated with the prefrontal cortex. The corresponding structure in birds is the nidopallium caudolaterale. Anatomic, neurochemical, electrophysiologic and behavioral studies show these structures to be highly similar, but not homologous. Thus, despite the presence (mammals) or the absence (birds) of a laminated forebrain, 'prefrontal' areas in mammals and birds converged over evolutionary time into a highly similar neural architecture. The neuroarchitectonic degrees of freedom to create different neural architectures that generate identical prefrontal functions seem to be very limited.
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THE NEURAL SUBSTRATES FOR SEQUENTIAL BEHAVIOR
Most of our behavior is composed of action sequences, like driving a car, brushing your teeth or human language. The pigeon is a commonly used model organism to investigate the principles of how sequences are learned and executed. However, so far virtually nothing was known about the underlying neural circuits in the pigeon brain.
In a recent study scientists of the IKN identified two structures that play a role for the execution of a learned sequence in the pigeon.
The scientist applied a so called serial reaction time task (SRTT). This kind of task requires subjects to respond quickly to a stimulus that appears at five different locations in a fixed sequence. In their study the scientists transiently inactivated different brain areas of the pigeons during the execution of this sequential task. Results show that two regions play a central role. On the one hand, the nidopallium caudolaterale (NCL), that is considered the avian equivalent to mammalian prefrontal cortex. On the other hand, the nidopallium intermedium medialis pars laterale (NIMl). This area is comparable in some characteristics to a nucleus of the neural system that generates song in song birds. Hence, this study is the first to identify components of a neural system for the execution of sequential behavior in the pigeon.
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The impact of asymmetrical light input on cerebral hemispheric specialization and interhemispheric cooperation
Specialization of the brain, where the left and right hemispheres perform different functions, is thought to have evolutionary advantages. But for many tasks, the hemispheres have to combine their expertise for optimal information processing. Scientists from the IKN studied hemispheric cooperation in pigeons, which have a visual system that develops asymmetrically in response to light stimulation. This allows comparison of integration capacities of lateralized (light-incubated) and non-lateralized (dark-incubated) animals. By presenting the left or right eye of the birds with different colour pairings, the scientists show that lateralized pigeons are able to integrate information learnt separately by the two hemispheres to solve a cognitive puzzle. In contrast, non-lateralized birds could not discriminate between colour pairings that required the combination of hemispheric-specific knowledge. This study provides first direct evidence that the efficiency of cooperation between the two brain halves depends on the development of hemispheric specialization, based on the experiences of the embryo.
Manns, M. & Römling, J. (2012). The impact of asymmetrical light input on cerebral hemispheric specialization and interhemispheric cooperation. Nature Communications, doi: 10.1038/ncomms1699.
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The Neural Landscape as seen with the 5-HT1A-receptor
The 5-HT1A receptor is the most widespread serotonin receptor type and is involved in various functions like depression, schizophrenia, Alzheimer’s disease, and eating disorders. Our knowledge about the distribution of 5-HT1A receptors in birds is extremely limited. Therefore, a team of neuroanatomists and biopsychologists from the universities of Düsseldorf and Bochum analyzed the distribution of 5-HT1A receptor binding sites in the pigeon brain using quantitative in vitro receptor autoradiography with the selective radioligand [3H]-8-Hydroxy-2-(di-n-propylamino)tetralin ([3H]-8-OH-DPAT). What they discovered is a completely new landscape of neural subdivisions that hints to functional specializations that were unknown before. The picture of the entopallium shown here is a nice example for this new landscape that testifies the existence of new subdivisions. In addition, the regional pattern of distribution of 5-HT1A receptors displays a scattering similar to brain structures of mammals, furthering the discussion on the comparison of the avian and the mammalian brain.
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Hemispheric asymmetries: The comparative view
Hemispheric asymmetries play an important role in almost all cognitive functions. For more than a century, they were considered to be uniquely human but now an increasing number of findings in all vertebrate classes make it likely that we inherited our asymmetries from common ancestors. In a new review article in Frontiers in Comparative Psychology, IKN researchers explain how studying animal models could provide unique insights into the mechanisms of lateralization. Three avenues of research are outlined by providing an overview of experiments on left-right differences in the connectivity of sensory systems, the embryonic determinants of brain asymmetries, and the genetics of lateralization. All these lines of studies could provide a wealth of insights into human asymmetries that should and will be exploited by future analyses.
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Hemispheric asymmetries modulate cognitive flexibility
In the present study a team of IKN scientists investigated the relevance of hemispheric asymmetries for cognitive control processes using a lateralized version of the task switching paradigm.
ERPs were recorded and the neural sources of the ERPs were reconstructed using standardised low resolution brain electromagnetic tomography (sLORETA).
A left lateralization of the N1 that was mediated by activation in the left extrastriate cortex as well as a greater positivity of the P3b were observed after stimulus presentation in the
RVF compared to the LVF. These findings reveal that FCAs are an important modulator of executive functions related to cognitive flexibility.
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When control fails....
There is growing interest in understanding the neurobiological foundations of attention.
Since dopamine is one of the most important neurotransmitters regulating attention processes, we aimed to examine whether attentional processes in a change detection task (biased competition paradigm) are modulated by dopamine signaling. Therefore, we investigated the influence of two polymorphisms of the dopaminergic system, i.e., Val158Met (rs4680) in the catechol-O-methyltransferase (COMT) and a variable number of tandem repeats polymorphism (VNTR, rs28363170) in the dopamine transporter (DAT1). Based on previous research, it is known, that the COMT Met allele results in lower enzyme activity and is therefore related to enhanced PFC dopamine signalling. In this study with 216 Caucasian subjects, we found that homozygous Met/Met allele carriers had difficulties when performing the biased competition task, particularly showing the greatest difficulties in case cognitive and behavioural flexibility was necessary and the required reaction was not part of the subject’s primary task set.
Contrary, no differences between the two genotype groups were evident, when an attentional conflict emerged and attentional control was needed for adequate responding.
With respect to other studies examining mechanisms of attentional functions in different paradigms, the results suggest that behavioural flexibility and attentional control as two execeutive subprocesses are differentially influenced by genetic polymorphisms within the dopaminergic system.
Schulz, S., Arning, L., Pinnow, M., Wascher, E., Epplen, J.T., Beste, C. (2012). When control fails: Influence of the prefrontal but not striatal dopaminergic system on behavioural flexibility in a change detection task. Neuropharmacology, 62, 1028-1033.
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The Fate of the Memory Trace: Brochure Release!
From 4th to 23rd of September 2011 we had the great pleasure of hosting the first “European Campus of Excellence” in Neuroscience at the Ruhr University Bochum. Over a period of three weeks thirty truly gifted students from all over Europe visited Bochum to deepen their knowledge in memory research. The present volume is a compilation of many of those ECE memories proving that our research is not only relevant to understanding human behavior but can also be a lot of fun for students, scholars and laymen. Enjoy Reading!
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Emmy Noether Group of Christian Beste accepted
Our seamless stream of thoughts and actions cloud be one of the greatest mysteries of the mind. This mystery is the ease with which we constantly and effortlessly chose one thing to do and many other things to let. Even more miraculously, we sometimes switch to a mode in which we can work in parallel on some tasks to then switch back to a serial mode of working. Often this flexibility of our mind was discussed in a corticocentric way, as if our cortex does it all. Now, the newly accepted and DFG-funded Emmy Noether group of Christian Beste set sails to completely change perspectives. In a grand effort that involves psychological, genetic, neurological, electrophysiological, theoretical, and imaging-based approaches, he and his team is dedicated to find crucial answers to the mysteries of the parallel and/or serially organized mind by focusing on the intricacies of the basal ganglia. The reviewers of the DFG were deeply impressed with the 5 year plan and decided to generously support this endeavor. By acquiring an Emmy Noether group, Christian is eligible to create his own independent research unit that is associated with the Biopsychology lab.
CONGRATULATIONS CHRISTIAN !!!
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A MATLAB-TOOLBOX FOR THE COMPUTATION OF STANDARDIZED EFFECT SIZES
The overwhelming majority of research in the neurosciences employs p-values stemming from tests of statistical significance to decide on the presence or absence of an effect of some treatment variable. Although a continuous variable, the p-value is commonly used to reach a dichotomous decision about the presence of an effect around an arbitrary criterion of 0.05. This analysis strategy is widely used, but has been heavily criticized in the past decades. To counter frequent misinterpretations of p-values, methodologists advocate complementing or replacing p-values with measures of effect size (MES). Many psychological, biological, and medical journals now recommend reporting appropriate MES. One hindrance to the more frequent use of MES may be their scarcity in standard statistical software packages. Also, the arguably most widespread data analysis software in neuroscience, MATLAB, does not provide MES beyond correlation and receiver-operating characteristic analysis. In our article, we review the most common criticisms of significance testing and provide several neuroscience examples where usage of MES conveys insights not amenable through the use of p-values alone. We introduce an open-access MATLAB toolbox providing a wide range of MES to complement the frequently used types of hypothesis tests, such as t-tests and analysis of variance. The accompanying documentation provides calculation formulae, intuitions for interpretation, and example calculations for each measure. The toolbox described in this article is usable without sophisticated statistical knowledge and should be useful to neuroscientists wishing to enhance their repertoire of statistical reporting.
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Doctoral Thesis - Conny Hahn
Conny Hahn successfully graduated on the 28th of November 2011 at the IGSN and was awarded with a PhD in Neuroscience. Conny submitted a thesis consisting of four papers on the effects of smoking on language asymmetry and attention. She could show that smoking, possibly via the cellular effects of nicotine, is able to alter functional brain asymmetries and attentional resources. Some of these effects show a clear sex-dependency. Most interestingly, Conny was able to show that if one controls for cigarette consumption, asymmetries in schizophrenic patients are no different from controls. Thus, some of the effects of schizophrenia on cerebral asymmetries might arise due to the heavy nicotine consumption of these patients. The international committee was impressed with Conny's contributions and decided to award her the title PhD of Neuroscience with the grade magna cum laude.
CONGRATULATIONS CONNY !!!
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Doctoral Thesis - Sebastian Ocklenburg
Sebastian Ocklenburg successfully graduated on the 25th of November 2011 in the Faculty of Psychology. He so much impressed the committee with his outstanding thesis and his strong defense that they unanimously decided to grade his doctoral project with a summa cum laude. Given the high threshold for this grade in our Faculty, this is an extremely rare and very prestigious event. Sebastian submitted a publication-based thesis with six papers in which he analyzed the phylogenetic, ontogenetic, genetic, and neuronal mechanisms of cerebral asymmetries. He was able to show that vocal asymmetry has a long evolutionary history, that experience-based factors shape human handedness, and that early neuronal processes guided language lateralization. In addition, he identified a genetic association for language asymmetry.
CONGRATULATIONS SEBASTIAN !!!
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Multisensory interactions in individuals with a congenital absence of the Corpus callosum
Callosal agenesis is a condition in which the Corpus callosum – the largest nerve fiber bundle connecting the two cerebral hemispheres – is developmentally absent due to genetic or environmental factors. Although this implies an absence of more than 180 million nerve fibers, past research revealed that the brain’s reorganization power may allow for a compensation for this malformation in certain unisensory tasks, e.g. by an increased use of other pathways such as the anterior commissure. Until now, however, potentials and limits of the brain’s plasticity have not been investigated in experimental setups which involve interactions between different sensory modalities. Therefore, a team of Biopsychologists from Hamburg and Bochum investigated five individuals with callosal agenesis in a visuotactile interaction task, the Crossmodal Congruency Task, which involves speeded tactile judgments in accompaniment of visual distractors. Results showed that interactions between vision and touch did not differ between individuals with callosal agenesis and healthy controls. This implies that the Corpus callosum is not necessary for visuotactile perception per se, and that early reorganization mechanisms may compensate for the absence of the corpus callosum.
Wolf, C.C., Ball, A., Ocklenburg, S., Otto, T., Heed, T., Röder, B., Güntürkün O. (2011). Visuotactile interactions in the congenitally acallosal brain: evidence for early cerebral plasticity. Neuropsychologia, 49, 3908-3916.
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Telencephalic Organization of the Olfactory System in Homing Pigeons
There is something mysterious about olfaction. It is the only sense that directly enters the forebrain without a thalamic relay. It also has tight links with the limbic system; creating the myth that olfaction is a strong gateway into emotional memory. Pigeons also use olfactory cues to navigate over unfamiliar areas, and any impairment of the olfactory system generates remarkable reduction of homing performance. This special function of olfaction is also lateralized: Studies suggest a critical involvement of the right olfactory bulb (OB) and the left piriform cortex (CPi) for initial orientation. Unfortunately, the structural organization of the olfactory system is by far not clarified yet. Thus, a team of Biopsychologists from Bochum and Witwatersrand (South Africa) re-analyzed the system by antero- and retrograde tract tracing with biotinylated dextran amine and choleratoxin subunit B, and especially evaluated quantitative differences in the number of cells in the OB innervating the left and right CPi. They verified a strong bilateral input to the CPi, and the prepiriform cortex (CPP), as well as small projections to the ipsilateral medial septum and the dorsolateral corticoid area and the nucleus taeniae of the amygdala in both hemispheres. The adjacent picture depicts some of the olfactory components within a 3D-view of the pigeon brain. However, the authors could not reveal any asymmetries within in the projections described. Thus, the functional lateralization of the olfactory system is not simply based on differences in the number of projecting axons of the major processing streams.
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Mapping spikes to sensations
Single-unit recordings conducted during perceptual decision-making tasks have yielded tremendous insights into the neural coding of sensory stimuli. In such experiments, detection or discrimination behavior (the psychometric data) is observed in parallel with spike trains in sensory neurons (the neurometric data). Frequently, candidate neural codes for information read-out are pitted against each other by transforming the neurometric data in some way and asking which code’s performance most closely approximates the psychometric performance. The code that matches the psychometric performance best is retained as a viable candidate and the others are rejected. In following this strategy, psychometric data is often considered to provide an unbiased measure of perceptual sensitivity. It is rarely acknowledged that psychometric data result from a complex interplay of sensory and non-sensory processes and that neglect of these processes may result in misestimating psychophysical sensitivity. This again may lead to erroneous conclusions regarding the adequacy of neural candidate codes. In this review, we first discuss requirements on the neural data for a subsequent neurometric-psychometric comparison. We then focus on different psychophysical tasks for the assessment of detection and discrimination performance and the cognitive processes that may underlie their execution. We discuss further factors that may compromise psychometric performance and how they can be detected or avoided. We believe that these considerations point to shortcomings in our understanding of the processes underlying perceptual decisions, and therefore offer potential for future research.
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Aging induces ‚changes in genotype effcts' – evidence from the BDNF Val66Met polymorphism
In this study we examined the relevance of the functional brain-derived neurotrophic factor (BDNF) Val66Met polymorphism as a modulator of task-switching performance in healthy elderly by using behavioral and event-related potential (ERP) measures. Task switching was examined in a cue-based and a memory-based paradigm. Val/Val carriers were generally slower, showed enhanced reaction time variability and higher error rates, particularly during memory-based task switching than the Met-allele individuals. On a neurophysiological level these dissociative effects were reflected by variations in the N2 and P3 ERP components. The task switch-related N2 was increased while the P3 was decreased in Met-allele carriers, while the Val/Val genotype group revealed the opposite pattern of results. In cue-based task-switching no behavioral and ERP differences were seen between the genotypes. These data suggest that superior memory-based task-switching performance in elderly Met-allele carriers may emerge due to more efficient response selection processes. The results implicate that under special circumstances the Met-allele renders cognitive processes more efficient than the Val/Val genotype in healthy elderly, corroborating recent findings in young subjects.
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On the role of fronto-striatal circuits for 'controlled' and ‚habitual' action selection - insights from response inhibition in Huntington's disease gene mutation carriers
Fronto-striatal loops play an important role action selection processes, especially when discordant sensory and contextual information has to be integrated to allow adequate selection of actions. Yet, it is widely unknown how far changes in the precision of neural synchronization processes are induced by only slight dysfunctions of striatal neural inter-connectivity and in how far such slight changes may affect action selection processes. To elucidate the role of fronto-striatal interactions, these processes may be examined in neurodegenerative basal ganglia disorders. We investigated these processes in a neurogenetic, degenerative disorder (i.e. Huntington's disease) in a modified Go/Nogo task, while assessing neural synchronization processes by means of phase-locking factors (PLFs) as derived from event-related potentials (ERPs). The results show that gene mutation carriers, who have not yet developed clinical signs of this movement disorder (i.e., pre-HDs) only encounter problems in response inhibition, when discordant contextual information and sensory input have to be integrated. No deficits were evident, when response inhibition can be based on more habitual stimulus–response mappings, i.e., when contextual and sensory information were congruent. While 'habitual' action selection is unaffected by changes in striatal structures influencing reliability of neural synchronization processes, efficient 'controlled' processes of action seem to be closely dependent upon highly reliable neural synchronization processes. The neurophysiological analysis suggests that especially pre-motor inhibition processes (Nogo-N2) are affected. This was most strongly reflected in a decline in the degree of phase-locking in the Nogo-N2 range. Deficits in pre-HDs seem to emerge as a consequence of phase-locking-behavioural decoupling. Of clinical interest, declines in the precision of phase-locking depended on the amount of the individual's mutant huntingtin exposure and predicted the probability of disease manifestation in the next five years. This suggests that phase-locking parameters may prove useful in future studies evaluating a possible function as a biomarker in Huntington's disease.
Beste C., Ness V., Falkenstein M., Saft C. (2011). On the role of fronto-striatal neural synchronization processes for response inhibition – evidence from ERP phase synchronization analyses in pre-manifest Huntington's disease gene mutation carriers. Neuropsychologia, 49, 3484-3493.
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Adaptive criterion setting in perceptual decision making
In perceptual decision making tasks, subjects are required to sort a range of stimuli into two or more categories. From the viewpoint of the experimenter, this is a psychophysical task: the subject tries to decide on the basis of sensory evidence which category a given stimulus belongs to. Thus, the subject is assumed to attempt to maximize accuracy. However, when the subjects are animals, conditions may change: to perform well in a behavioral experiment, animals are usually rewarded for each correct response. Thus, from the viewpoint of the animal subject, the task is more about foraging than about psychophysics.
In a newly released paper, Maik Stüttgen, Ali Yildiz and Onur Güntürkün report that rewarding animal subjects for one kind of classification more often than for another kind heavily biases their choice behavior. More importantly, the animals were shown to integrate sensory evidence - which category the stimulus belongs to - and reward preference - which category response is rewarded more often - in a statistically optimal fashion. Moreover, the subjects did so in a suprisingly brief amount of time, which calls into question that they attempted to maximize expected value as decision goal - a central assumption of signal detection theory.
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Variations in the GRIN2B gene are associated with risky decision-making
In recent studies by our group we accumulated evidence that the effect of certain genetic polymorphisms varies across cognitive processes. The polymorphisms 5-HT1A C(-1019)G (Beste et al., 2011) and TNF-alpha -308G-A (Beste et al., 2011) have been shown to participate in the modulation of cognitive control. For the first time, the present study provides evidence that variations in the GRIN2B gene are associated with decision making. The dopaminergic system is known to modulate decision-making. As N-methyl-d-aspartate (NMDA) receptors strongly influence dopaminergic function, it is conceivable that the glutamatergic system is also involved in decision-making. We examined whether polymorphisms in the N-methyl-d-aspartate receptor 2B subunit gene (GRIN2B) influence decision-making using the Iowa Gambling Task (IGT). In total, 245 (n = 245, 127 female) healthy German students were included in the analysis. Two synonymous SNPs in exon 13, rs1806191 (H1178H) and rs1806201 (T888T) showed the strongest association with aspects of IGT performance. Females with a CC allele in rs1806201 made less use both of a win-stay strategy and demonstrated more exploratory behaviour during task execution. For rs1806191, we found a strong additive effect in usage of a win-stay strategy. This, partly sex-dependent, correlation of the win-stay/lose-shift behaviour with GRIN2B genotypes suggests that healthy individuals with certain GRIN2B variations respond differently to ambiguous conditions, possibly by altered perception of wins and losses. These findings underline the necessity to integrate the glutamatergic system when examining decision-making processes.
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Variation in the NMDA receptor 2B subunit gene GRIN2B is associated with differential language lateralization
In the current study, a team of scientists from the IKN and the Department of Human Genetics investigated whether variations in the N-methyl-d-aspartate receptor 2B subunit gene (GRIN2B) influence language lateralization and handedness in healthy individuals. In a cohort of 424 genetically unrelated participants a significant association between the synonymous GRIN2B variation rs1806201 and language lateralization assessed using the dichotic listening task, but not handedness, was observed. These findings suggest for the first time that variation in NMDA-receptors contributes to the interindividual variability of language lateralization.
Ocklenburg, S., Arning, L., Hahn, C., Gerding, W.M., Epplen, J.T., Güntürkün, O., Beste, C. (2011). Variation in the NMDA receptor 2B subunit gene GRIN2B is associated with differential language lateralization. Behavioural Brain Research, 225, 284-289.
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Mapping Prefrontal Areas
Mapping a territory is always the first step of analysis. So, mapping the nidopallium caudolaterale (NCL), an avian functional analogue to the mammalian prefrontal cortex, in 1993 was a prerequisite for subsequent research. However, a more comprehensive and truly comparative mapping was meanwhile needed. Therefore, scientist from the Institute of Brain Research in Düsseldorf and Biopsychologists from Bochum analyzed binding site densities of AMPA, NMDA, Kainite, GABAA, M1, M2, and nicotinic nACh, a1, a2, 5-HT1A, and D1-like receptors using quantitative in vitro receptor autoradiography. They compared the receptor architecture of the pigeons’ NCL, with prefrontal areas in rats and humans. Their findings enable a novel delineation of the avian NCL from surrounding structures and a further parcellation into medial and lateral components. Comparisons of the NCL with the rat and human frontal structures showed differences in the receptor distribution, particularly for glutamate receptors, but also revealed highly conserved features like for GABAA, M2, nACh and D1-like receptors. Assuming a convergent evolution of avian and mammalian prefrontal areas, these results support the hypothesis that specific neurochemical traits provide the molecular background for higher order processes such as executive functions.
Herold, C., Palomero-Gallagher, N., Hellmann, B., Kröner, S., Theiss, C., Güntürkün, O., Zilles, K. (2011). The receptorarchitecture of the pigeons' nidopallium caudolaterale – an avian analogue to the prefrontal cortex. Brain Structure & Function, 216, 239-254.
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Maik Stüttgen wins Attempto Research Prize for outstanding work in neuroscience
The board of trustees of the Attempto Foundation of the University of Tübingen has decided to award Maik Stüttgen this year's Attempto Award for his recent paper, "Integration of vibrotactile signals for whisker-related perception in rats is governed by short time constants: comparison of neurometric and psychometric performance", appeared in The Journal of Neuroscience last year.
The paper investigated mechanisms of sensory coding in the primary somatosensory ("barrel") cortex of the rat. The animals' ability for detecting multi-pulse tactile stimuli was measured simultaneously with the activity of single neurons in barrel cortex. The authors constructed a theoretical model which successfully relates neural response patterns to both detection probabilities and reaction times of the animals, thus bridging the gap between neural activity on the one hand and sensation and perception on the other.
The award ceremony will take place on October 12th Tübingen.
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Is a ‚risk allele' always risky? Evidence how 'risk alleles' confer a benefit to its carriers
In recent studies by our group we accumulated evidence that the effect of certain genetic polymorphisms varies across cognitive processes. The results call in question, if a ‘risk allele’ necessarily confers a disadvantage to its carriers. In this study we provide further evidence on this issue.
Cognitive control processes may depend on contextual information, sometimes improving performance, but impairing performance if expectancies about forthcoming events induce pre-potent responses. The neurobiological bases of these effects are not understood. Here, we examine context-dependent variations of response control processes using the AX-CPT task with respect to the relevance of the functional serotonin 1A receptor polymorphism (5-HT1A C(−1019)G). The results show that, when context information is helpful to drive behavioural performance, carriers of the −1019G allele reveal compromised cognitive control. Yet, they show enhanced task performance when strong context representations would lead to declines in behavioural control. These findings are paralleled by modulations of the (Nogo)-P3 ERP-component. These results show for the first time that, even though the −1019G allele enhances the risk to develop anxiety disorders, it also confers an advantage to its carriers in terms of better cognitive control processes in conditions where contextual information compromises cognitive control. Effects of the 5-HT1A C(−1019)G polymorphism were further modulated by anxiety sensitivity. As the functional effect of the 5-HT1A C(−1019)G polymorphism has previously been shown to be rather specific for serotonergic 1A autoreceptors in the dorsal raphe nucleus (DRN), the results suggest that contextual modulations in cognitive control may be exerted by the DRN.
Beste, C., Domschke, K., Radenz, B., Falkenstein, M., Konrad, C. (2011). The functional 5-HT1A receptor polymorphism affects response inhibition processes in a context-dependent manner. Neuropsychologia, 49, 2664-2672.
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Türöffner Tag am 10.Juli 2011
Was ist eigentlich das Gehirn und wie funktioniert es genau? Am 10. Juli bietet das IKN, im Rahmen des von der "Sendung mit der Maus" organisiertem Türöffner Tag, einen Workshop an, in dem Kinder mehr über das wohl wichtigste Organ unseres Körpers erfahren können. Zusammen mit Forschern und Studenten des IKN werden die Besucher Gehirnmodelle aus Knete anfertigen. Natürlich können alle Fragen zum Thema "Gehirn und Nervensystem" gestellt werden.
Das Institut öffnet seine Tür am 10. Juli ab 14 Uhr für Kinder ab 4 Jahren.
Ort: Ruhr-Uni-Bochum, Universitätsstraße 150, Institut für kognitive Neurowissenschaften, GAFO 05/609. Die Veranstaltung dauert 1 bis 2 Std. Anmeldungen bitte per Mail an: firstname.lastname@example.org
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NEW DFG-FUNDED RESEARCH PROJECT ON DECISION MAKING
Maik Stüttgen has been granted a research project on the neural basis of adaptive decision-making. The project will be funded for three years and will focus on neural correlates of subjective value.
Classical models of decision making assume that the objective value of different choice options is transformed to subjective value, i.e. the expected utility of a choice outcome as assessed by an individual subject. Subjective value is known to be influenced by a variety of factors, such as the magnitude of a gain or a loss. Recent studies have suggested that subjective value is coded by the spiking activity of individual neurons in forebrain areas. However, little is known about the properties of the value representation when negative consequences, such as loss of reinforcers, are encountered. Furthermore, the plasticity of these representations has not been characterized. In the present project, pigeons will be exposed to complex perceptual discrimination tasks in a non-stationary environment. Concomitant unit recordings in forebrain areas will enable to relate adaptive decision making to changes in neuronal coding properties.
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Passive makes perfect – depending on what you see
Cellular studies have focused on long-term potentiation (LTP) and long-term depression (LTD) to understand requirements for persistent changes in synaptic connections. Here we adapted LTP/LTD-like protocols to visual stimulation to alter human visual attention and behavior. In a change-detection task, participants reported luminance changes against distracting orientation changes. Subsequently, they were exposed to passive visual high- or low-frequency stimulation of either the relevant luminance or irrelevant orientation feature. LTP-like high-frequency protocols using luminance improved ability to detect luminance changes, whereas low-frequency LTD-like stimulation impaired performance. In contrast, LTP-like exposure of the irrelevant orientation feature impaired performance, whereas LTD-like orientation stimulation improved it. This is the first study showing that mechanisms used in cellular studies can also be used in vivo to alter human behavior and supports cellular, neurophysiological studies showing that these mechanisms alter synaptic strength. Future research may evaluate the potential of this technique for clinical interventions.
Beste, C., Wascher, E., Güntürkün, O., Dinse, H. R. (2011). Improvement and impairment of visually guided behavior through LTP- and LTD-like exposure-based visual learning. Current Biology, 21, 876-882.
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Onur Güntürkün becomes a member of the Editorial Board of Behavioural Processes
Onur Güntürkün becomes a member of the Editorial Board of Behavioural Processes (Elsevier). Behavioural Processes publishes research on animal behavior from behavioral analytic, cognitive, ethological, ecological and evolutionary points of view. The journal plans to make a strategic shift to incorporate contributions from neuroscience without losing its strength in the field of ethology-minded behavioral analyses. Troubled waters; Onur Güntürkün was seen as a person to help in this transition.
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Schizophrenia, Smoking, and Language Asymmetry: A new link
Schizophrenia has been associated with deficits in functional brain lateralization and some authors even argue that the reduction of asymmetry produces the psychosis. However, there is one major and often overlooked confound: Schizophrenic patients are extreme cigarette smokers. This association is very interesting, because a team from the Bochum Biopsychology Department could recently show that smoking can reduce auditory language asymmetry. Thus, the altered laterality pattern in schizophrenia could, at least in part, result from secondary artifacts due to smoking rather than being a pure cause of the disease itself. To test this hypothesis, the present study examined auditory language lateralization in 67 schizophrenia patients and in 72 healthy controls. Again it was found that smoking reduces language lateralization. Most importantly, no further effect of schizophrenia on language asymmetry was found. This opens the tantalizing possibility that at least some of the asymmetry alterations in schizophrenia are not a primary consequence of the disease but a secondary effect of increased smoking habits.
Hahn, C., Neuhaus, A. H., Pogun, S., Dettling, M., Kotz, S. A., Hahn, E., Brüne, M., Güntürkün, O. (2011). Smoking reduces language lateralization: A dichotic listening study with control participants and schizophrenia patients. Brain Cogn., 76, 300-309.
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Mental rotation does not account for sex differences in left–right confusion
Several studies have demonstrated that women believe they are more prone to left–right confusion than men. However, while some studies report that there is also a sex difference in LRC tasks favouring men, others report that men and women perform equally well. Recently, it was suggested that sex differences only emerge in LRC tasks when they involve mental rotation. To test this assumption, a team of biopsychologists from Durham University (Durham, England) together with biopsychologists from Bochum tested 91 participants with two LRC tasks. To rule out the possibility that sex differences in LRC are confounded by sex differences in mental rotation, male and female participants were matched for mental rotation performance. These matched participants showed robust sex differences in favour of men in all LRC measurements.
Ocklenburg, S., Hirnstein, M., Ohmann, H. A., Hausmann, M. (2011). Mental rotation does not account for sex differences in left–right confusion. Brain and Cognition, 76, 166-171.
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Medal of Merit of North Rhine-Westphalia for Onur Güntürkün
On the 7th of April 2011, Onur Güntürkün was awarded in Düsseldorf with the Medal of Merit of North Rhine-Westphalia. As explained by Minister-President Hannelore Kraft in her laudatio, the medal was awarded for his scientific success and his contribution to the academic exchange between Germany and Turkey.
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Dr. Christian Beste has been elected in the Editorial Advisory Board of Neuropsychologia
With april the 22nd Christian Beste has been appointed as a member of the Editorial Advisory Board of Neuropsychologia. Neuropsychologia is a prestigeous, traditional journal in the field of cognitive neuroscience. Together with the other members of the Editoral Advisory Board his task is to further improve journal standards by monitoring the editorial policy of the journal in terms of coverage, level and quality of the papers.
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Lateralized neural mechanisms underlying the modulation of response
In the present study a team of IKN scientists investigated the temporal and spectral dynamics as well as the cortical networks underlying the interaction of hemispheric asymmetries and executive functions related to response inhibition. To this end, event-related potentials were recorded during tachistoscopic presentation of verbal 'Go' and 'Nogo' stimuli in the left (LVF) and the right visual field (RVF). Participants committed fewer false alarms to verbal Nogo stimuli presented in the RVF than to stimuli presented in the LVF. This asymmetry was paralleled by the neurophysiological data. The Nogo-N2 and related delta frequency band power were stronger when response inhibition was driven by stimuli presented in the LVF, implying a stronger response conflict. This effect was mediated by stronger activations in bilateral medial-prefrontal and especially left parietal networks. These findings show that hemispheric dominances in information processing can induce differences in demands on cognitive processes operating via bilateral networks that ultimately drive behavioural asymmetries.
Ocklenburg, S., Güntürkün, O., Beste, C. (2011). Lateralized neural mechanisms underlying the modulation of response inhibition processes. Neuroimage, 55, 1771-1778.
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It's official: First European Campus of Excellence (ECE) hosted by us
From September 4th – 25th, 2011, the first ECE course in neuroscience will be held at the Ruhr-University Bochum. The ECE is promoting a European network of summer schools that bring eminent scientists and 30 highly talented and gifted European (plus Israel, Norway, Switzerland, and Turkey) students together. Central theme of the summer course in Bochum is: "The Fate of the Memory Trace: Learning, remembering and forgetting from molecules to behavior." Over a period of 3 weeks the students attend lectures in the morning and practical lab excercises in the afternoon.The topics of the first week are "Acquisition and Consolidation". In week 2 the students deepen their knowledge on "Retrieval and the Memory System". Week 3 is dedicated to "Extinction and Forgetting". At weekends our guests get to know more about the Ruhr area and, of course, each other. The Campus in Bochum is possible due to the generous funding of Stiftung Mercator. The selected students receive stipends covering travel, housing and full board. Onur Güntürkün is in charge of organizing the summer school.
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Laterality in the rubber hand illusion
In patient studies, impairments of sense of body ownership have repeatedly been linked to right-hemispheric brain damage. In the current study a team of IKN scientists from the Neuro- and Biopsychology labs investigated lateralisation for sense of body ownership in healthy adults. To this end the rubber hand illusion was elicited on both hands of left- and right-handed participants. The vividness of the illusion was measured by subjective self-reports as well as by skin conductance responses to watching the rubber hand being harmed. Handedness did not affect the vividness of the illusion, but a stronger skin conductance response was observed, when the illusion was elicited on the left hand. These findings suggest a right-hemispheric dominance for sense of body ownership in healthy adults.
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TNF-alpha modulates cognitive control processes in a double-dissociated fashion
Neuroimmunological factors may modulate brain functions and are important to understand the molecular basis of cognition. Previously, we have been shown that these factors modulate functions mediated by different cortical areas in a dissociated fashion. In the current study we ask, if such dissociated effects are also evident between adjacent functional fronto-striatal loops. Since the basal ganglia are neurobiologically heterogeneous, different cognitive functions mediated by basal ganglia-prefrontal loops (response inhibition and error processing) may not necessarily be uniformly affected. Response inhibition and error processing functions were examined using event-related potentials (ERPs) and subjects were genotyped for the functional TNF-alpha -308G-A polymorphism. We show a double-dissociated effect of the functional TNF-alpha -308G-A polymorphism on response inhibition and error processing. While response inhibition functions were more effective in the AA/AG genotype group, error monitoring functions are adversely affected in this genotype group. In the GG genotype group, the pattern of results was vice versa. The results refine the view of the effects of TNF-alpha on cognitive functions.
Beste, C., Güntürkün, O., Baune, B. T., Domschke, K., Falkenstein, M., Konrad, C. (2011). Double dissociated effects of the functional TNF-alpha -308G/A polymorphism on processes of cognitive control. Neuropsychologia, 49, 196-202.
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The effects of parental hormones on working memory processes
Men outperform women in mental rotation by about one standard deviation. Prenatal exposure to testosterone has been suggested as one cause. In animals it has been shown that a female fetus located between two male ones is exposed to higher levels of testosterone. It is still unclear whether intra-uterine hormone transfer exists in humans. Therefore, the influence of an intra-uterine presence of a male co twin was studied in female fraternal twins (N=200). Women with a male co-twin outperformed women with a female co-twin by about a third standard deviation. In a no-twin control group (N=200), performance of women with a slightly older sibling did not depend upon the sibling's sex. These findings provide preliminary support for the theory of an influence of prenatal testosterone on mental rotation performance.
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How BDNF and affective status modulate pre-attentive visual processes
The brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, is involved in nerve growth and survival. Especially, a single nucleotide polymorphism (SNP) in the BDNF gene, Val66Met, has gained a lot of attention, because of its effect on activity-dependent BDNF secretion and its link to several cognitive functions, especially memory processes. In this study we investigated the functional relevance of BDNF for pre-attentive visual sensory memory processes. Since BDNF is also discussed to be involved in the pathogenesis of depression, we additionally tested for possible interactions with depressive mood. The BDNF Val66Met polymorphism significantly influences iconic-memory performance, with the combined Val/Met-Met/Met genotype group revealing less time stability of information stored in iconic memory than the Val/Val group. Furthermore, this stability was positively correlated with depressive mood exclusively in the Val/Val genotype group. Thus, these results show that the BDNF Val66Met polymorphism has an effect on pre-attentive visual sensory memory processes and also suggests that sensory memory processes may proof useful in the search for cognitive endophenotypes of depression, which may be target for future studies.
Beste, C., Schneider, D., Epplen, J. T., Arning, L. (2011). The functional BDNF Val66Met polymorphism affects functions of pre-attentive visual sensory memory processes. Neuropharmacology, 60, 467-471.
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Effects of dopaminergic treatment on action selection mechanisms in Parkinson's disease
Action selection mechanisms depend upon fronto-striatal structures and are impaired in neurodegenerative basal ganglia disorders. Dopaminergic treatment of Parkinson's disease lingers clinical symptoms, but the question what effects these treatments have neurophysiological mechanisms underlying complex action selection processes have only rarely been addressed. We examined effects of short-term and long-term dopaminergic medication in Parkinson's disease on conflict monitoring or response selection processes. These processes were examined using event-related potentials (ERPs), while subjects performed a stimulus-response (S-R) compatibility task. An extended sample of young and elderly controls, Parkinson's disease patients with a medication history (PDs) and initially diagnosed, drug-naïve de novo PD patients (de novo PDs) were enrolled. Both PD groups were measured twice (on and off-medication or before and 8 weeks after medication onset). The results show that dopaminergic intervention selectively reduced the pathologically enhanced response selection in compatible S-R relations. This medication effect was already evident after short-term treatment, not differing from long-term treatment and performance in elderly controls. Contrary, age-related attenuations of the N2 in incompatible S-R relations, probably reflecting impaired conflict processing or response control, are unaffected by medication. The results suggest that compatible and incompatible S-R relations demand different neuronal mechanisms within the basal ganglia, as only the former are affected by agonizing the dopaminergic system.
Willemssen, R., Falkenstein, M., Schwarz, M., Müller, T., Beste, C. (2011). Effects of aging, Parkinson’s disease, and dopaminergic medication on response selection and control. Neurobiol Aging, 32, 327-335.
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Proposal for the DFG Research Unit "Extinction Learning" accepted!
We can learn new information and are subsequently able to remember it. However, we are equally able to learn that once acquired information is no longer valid and cease to respond to it. While the initial process of acquisition of new knowledge is well studied, the process of extinction is far less understood. It is known that extinction involves a new learning process that is different and more complex than the initial acquisition of the CS-US-association. Extinguished responses do not disappear but can return following manipulations such as a change in context as in renewal paradigms. Within the scope of the Research Unit that is going to start working on 1st of January 2011, 8 labs from the universities of Bochum, Essen-Duisburg and Marburg plan to explore the neural, the behavioral, and the clinical mechanisms of extinction in various species, incl. humans. Using a highly interactive research strategy, they intend to harvest deep insights into both the common and the distinct mechanisms of extinction learning in different systems and organisms. By this, there is good hope to achieve translational insights between Basic and Clinical Science. Onur Güntürkün is the speaker of the Research Unit.
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Brain region counts: Dissociated effect of TNF-a on attention and action selection mechanism
There is growing interest to understand the molecular basis of complex cognitive processes. While neurotransmitter systems have frequently been examined, other, for example neuroimmunological factors have attracted much less interest. Recent evidence suggests that the A allele of the tumor necrosis factor alpha (TNF-alpha) 308G-A single nucleotide polymorphism (SNP; rs1800629) enhances cognitive functions. However, it is also known that TNF-a exerts divergent, region-specific effects on neuronal functioning. Thus the finding that the A allele is associated with enhanced cognitive performance may be due to regionally specific effects of TNF-alpha. To further elucidate the divergent role of TNF-alpha as a modulator for cognitive processes we examine associations between the TNF-alpha -308G-A single nucleotide polymorphism (rs1800629) and cognitive performance, utilizing a task that enables the assessment of occipito-parietal-medial prefrontal coupling. The results show a dissociative effect of the TNF- 308G-A SNP on ERPs reflecting attentional (N1) versus conflict and action selection processes [N2 and early-lateralized readiness potential (e-LRP)] between the AA/AG and the GG genotypes. Compared with the GG genotype group, attentional processes (N1) were enhanced in the combined AA/AG genotype group, while conflict processing functions (N2) and the selection of actions (LRP) were reduced. The results refine the picture of the effects of the TNF-alpha -308G-A SNP on cognitive functions and emphasize the known divergent effects of TNF-alpha on brain functions.
Beste, C., Baune, B. T., Falkenstein, M., Konrad, C. (2010). Variations in the TNF-alpha gene (TNF-alpha -308G/A) affect attention and action selection mechanisms in a double-dissociated fashion. J Neurophysiol, 104, 2523-2531.
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SMOKING AND SEX DIFFERENTIALLY AFFECT AUDITORY LANGUAGE LATERALIZATION
Smoking affects the neural architecture of auditory attention pathways via the nicotinergic acetylcholine transmitter system. These changes primarily occur during critical developmental periods, i.e., during embryonic development and adolescence. In addition, males and females appear to be differentially affected by the adverse effects of smoking, such these effects were found to be more detrimental in males than in females. This raises the question whether nicotine would also affect auditory language lateralization in men and women in different ways. To address this question, Biopsychologists from Bochum and Neuroscientists from the Aegean University in Izmir, Turkey, assessed auditory language lateralization in 90 healthy right-handed participants by a classic consonant-vowel syllable dichotic listening paradigm. Indeed, the results reveal that smoking impairs stimulus recognition in men, while women are not negatively affected. Moreover, the laterality index, which is usually biased towards the left (speech-dominant) hemisphere, is reduced in smoking men compared to non-smoking ones. In contrast, the laterality patterns of women remain unaltered by smoking. Given that a higher laterality is further associated with better performance in this task, these findings provide an exciting first step in elucidating the important role of smoking with respect the neuronal mechanisms underlying brain laterality.
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Lateralized and Non-Lateralized Visual Systems for Migration
Migratory birds like European robins are able to use white or monochromatic light from the short-wavelength spectrum up to 565 nm to orient according to a magnetic compass system. Compass orientation is based on radical pair processes and is lateralized in favor of the right eye. For robins this implies a northbound direction towards Sweden during their spring migration. If, however, light with a long-wavelength component is given, the animals are no longer able to use their right-eye based compass system and depart to a 'fixed direction' response that is eastbound. Now a team of scientists from Frankfurt and Bochum universities demonstrated that these two visual orientation systems are differently organized with respect to hemispheric asymmetries. Robins were tested with either the right or the left eye covered or with both eyes uncovered for their orientation under different light conditions. With 502 nm turquoise light, the birds showed normal compass orientation, whereas they displayed an easterly 'fixed direction' response under a combination of 502 nm turquoise with 590 nm yellow light. Monocularly right-eyed birds with their left eye covered were oriented under turquoise in their northerly migratory direction, under turquoise-and-yellow towards east. The response of monocularly left-eyed birds differed: under turquoise light, they were disoriented, reflecting a lateralization of the magnetic compass system in favor of the right eye, whereas they continued to head eastward under turquoise-and-yellow light. Thus, 'fixed direction' responses are not lateralized. Hence und long-wavelength light the animals are no longer able to use their right-eye based compass system and depart to a non-lateralized 'fixed direction' response that is eastbound.
Wiltschko, R., Gehring, D., Denzau, S., Güntürkün, O. and Wiltschko, W. (2010). Interaction of the magnetite-based receptors in the beak with the visual system underlying 'fixed direction' responses, Frontiers Zool., 7: 24.
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Variations in the Reelin gene (RELN) affect executive functions in healthy individuals
Executive functions such as set-shifting and maintenance are cognitive processes that rely on complex neurodevelopmental processes mediated by basal ganglia-prefrontal loops and the medial prefrontal cortex. To establish of basal ganglia-prefrontal loops, Reelin plays an important role in neurodevelopment. Although neurodevelopmental processes are mainly studied in animal models and in neuropsychiatric disorders, the underlying genetic basis for these processes under physiological conditions is poorly understood. We aimed to investigate the association between genetic variants of the Reelin (RELN) gene and cognitive set-shifting in healthy young individuals. The relationship between 12 selected single nucleotide polymorphisms (SNPs) of the RELN gene and cognitive set-shifting. We accounted for robust associations that were substantiated by subsequent haplotype analyses. The results suggest that variation in the REN gene affect processes of cognitive set-shifting and flexible rule adaptation and broadens the relevance of the RELN gene as a modulator for cognitive functions beyond neurological and/or psychiatric disorders.
Baune, B. T., Konrad, C., Suslow, T., Domschke, K., Birosiva, E., Sehlmeyer, C., Beste, C. (2010). The Reelin (RELN) gene is associated with executive function in healthy individuals. Neurobiol Learn Mem, 94, 446-451.
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Third DAAD PhDNet Autumn School in Delmenhorst
A delegation of our lab participated in the third autumn school of our DAAD-funded international PhD-program, taking part Sept. 19th-24th at the Hanse-Wissenschaftskolleg (HWK) in Delmenhorst. Doctoral fellows and their supervisors from Bochum, Izmir (Turkey) and Padua (Italy) came together for talks, vivid scientific discussions and poster sessions on both individual research projects and more general neuroscientific topics. Renowned scientists Josep Call from the MPI Leipzig, Germany, and Isabelle George from the CRNS in Rennes, France, completed the event as invited speakers. The doctoral fellows ran a competition for the best presentation and the best poster. For our lab, the autumn school was a success all down the line: We brought home all prizes. The picture below shows Sebastian Ocklenburg, the winner of the presentation prize, Felix Ströckens and Nils Kasties as winners of the poster prize, together with the organizational team, during the award ceremony.
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Magnetoreception of Directional Information in Birds Requires Nondegraded Vision
The magnetic compass orientation of birds is light dependent and is primarily mediated by the right eye. These findings make it likely that magnetic compass information is actually “seen” by the bird as a local change in its visual percept. The superiority of the right eye / left hemisphere in this process could then be a consequence of the superiority of the left hemisphere in discrimination tasks requiring object vision. Scientists from Frankfurt University and Biologists and Biopsychologists from Bochum have now conducted tests in the local geomagnetic field with European robins wearing goggles equipped with a clear and a frosted foil of equal optical translucence. Robins with a clear foil on the right eye and a frosted foil on the left eye oriented in the migratory direction as well as birds using both eyes. Birds with a frosted foil that blurred vision on the right eye and a clear foil on the left eye, in contrast, were disoriented. The publication in Current Biology is the first to show that avian magnetoreception requires, in addition to light, a nondegraded image formation along the projectional streams of the right retina. This suggests that the conversion of magnetic input into directional information requires processes that are also relevant for visual pattern recognition.
Stapput, K., Güntürkün, O., Hoffmann, K.-P., Wiltschko, R. and Wolfgang, W. (2010). Magnetoreception of directional information in birds requires non-degraded object vision. Curr. Biol., 20, 1259-1262.
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How pro-inflammatory cytokines affect working memory processes
There is a growing interest in how pro-inflammatory cytokines modulate cognitive processes, especially since these molecules do not affect every brain area in a uniform way. The tumor necrosis factor alpha (TNF-alpha) for example exerts neuroprotective and neurodegenerative effects, depending on brain region. While some research suggests enhancing effects of the TNF-alpha gene (TNF-alpha -308G/A) on cognitive function, further research is needed to clarify the association between the TNF-alpha gene and specific areas of cognitive performance including their neurophysiological correlates. In this study we examined associations of the TNF-alpha -308G/A single nucleotide polymorphism (rs1800629) with attention and mental rotation performance in an event-related potential (ERP) study. The results show that carriers of the -308 A allele display elevated attentional processes (i.e. a stronger N1) as compared to the GG genotype group. Mental rotation performance varied across genotypes only when demands on mental rotation were high. Here, carriers of the -308 A allele performed better than the GG genotype group. This is paralleled by the neurophysiological data. The finding of enhanced attentional and mental rotation performance in A allele carriers supports recent findings that the A allele of this single nucleotide polymorphism (SNP) enhances cognitive performance on a general measure of cognitive processing speed.
Beste, C., Heil, M., Domschke, K., Baune, B.T., Konrad, C. (2010). Associations between the tumor necrosis factor alpha gene (-308G->A) and event-related potential indices of attention and mental rotation. Neuroscience, 170, 742-748.
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Asymmetry of Change Blindness
Do you see the difference between the two pictures? No? Then you are in good company. If the two pictures would simply alternate on a monitor, you would instantly see the difference. However, when a brief pause or a blank (like the grey partition in our example) is interposed between the two pictures, a person can sometimes gaze for minutes at the constantly switching two figures (and their interposed partitions) without detecting even very large changes in the scene. This phenomenon is called Change Blindness and it is to some extent still a mystery. Very likely, change blindness critically depends on attentional mechanisms. Visuo-spatial attention is lateralized towards the right hemisphere (left visual field). Wouldn’t we then expect change blindness to be more pronounced in the right visual field? In two successive experiments, psychologists from Izmir and Bochum tested this assumption and could prove it. Indeed, subjects could detect changes significantly faster in the left visual field, irrespective of their eye movements. Thus, even in cases when they started with a saccade to the right side of the picture, they were more likely to detect the difference on the left side of the picture.
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How BDNF synchronizes our brain to adjust behaviour
Behavioural adaptation depends on the recognition of response errors and processing of this error-information. Error processing is a specific cognitive function crucial for behavioural adaptation. Even though synchronization processes are important in information processing, its role and neurobiological foundation in behavioural adaptation are not understood. The brain-derived-neurotrophic-factor (BDNF) strongly modulates the establishment of neural connectivity that determines neural network dynamics and synchronization properties. Therefore altered synchronization processes may constitute a mechanism via which BDNF affects processes of error-induced behavioural adaptation. We investigate how variants of the BDNF gene regulate EEG-synchronization processes underlying error processing. Subjects (N=65) were genotyped for the functional BDNF Val66Met polymorphism (rs6265). We show that Val/Val genotype is associated with stronger error-specific phase-locking, compared to Met allele carriers. Post-error behavioural adaptation seems to be strongly dependent on these phase-locking processes and efficacy of EEG-phase-locking-behavioural coupling was genotype dependent. After correct responses, neurophysiological processes were not modulated by the polymorphism, underlining that BDNF becomes especially necessary in situations requiring behavioural adaptation. The results suggest that alterations in neural synchronization processes modulated by the genetic variants of BDNF Val66Met may be the mechanism by which cognitive functions are affected.
Beste, C., Kolev, V., Yordanova, J., Domschke, K., Falkenstein, M., Baune, B.T. and Konrad, C., The role of the BDNF Val66Met polymorphism for the synchronization of error- specific neural networks, J Neurosci, 2010, 30: 10727-10733.
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Molecular Imaging during Homing
Pigeons use olfactory cues to navigate over unfamiliar areas when flying home. The left and the right hemispheres seem to play different roles in this process. In particular, the right olfactory bulb and left piriform cortex (the ‘cortical’-like area of olfactory representation) have been shown to be crucial for navigation. In a new study Biopsychologists from Bochum and Biologists from Pisa conducted a molecular imaging study in pigeons that had to home (or not) under different conditions. Imaging was done by the use of the immediate early gene ZENK that is activated when neurons are highly active. One group of pigeons was released from an unfamiliar site and had to fly home. On their way to the realease area they could smell and could use their olfactory sense when flying homeward. The second group was transported to the unfamiliar site (and could also smell everything), but was driven back without flying. The third group was released in front of the loft and had no trouble to find their way. In all groups, the nostrils of some pigeons were either occluded unilaterally or not. Released pigeons revealed the highest ZENK cell density in the olfactory bulb and the piriform cortex, indicating that very likely not smelling as such but the use of odours for homing from an unfamiliar site massively activates these structures. Only occlusion of the right olfactory bulb resulted in a decreased ZENK cell expression in the piriform cortex, whereas occlusion of the left nostril had no effect. This is the first study to reveal neuronal activation patterns in the olfactory system during homing. The data show that lateralized processing of olfactory cues is indeed involved in navigation over unfamiliar areas.
Es ist kaum zu glauben, aber Sabine Kesch hat gestern ihr 25jähriges Dienstjubiläum gefeiert. Seit so langer Zeit sorgt Sabine in der Biopsychologie, dass es den Tauben optimal geht. Sie fing zu einer Zeit an, in der dieser Lehrstuhl „Tierpsychologie“ hieß und der Chef Juan Delius. Später wurde Hans Markowitsch Professor des Lehrstuhls und benannte ihn in „Biopsychologie“ um. Noch später kam Onur Güntürkün. In all dieser Zeit hat Sabine die Tierpflege großartig organisiert und durchgeführt.
VIELEN DANK, SABINE!!!
Josine Verhaal successfully fulfilled her defence on the 15th of July 2010 in the International Graduate School of Neuroscience (IGSN) and was awarded with a PhD. Josine gave a very nice overview of her work in which she showed how neurons in the entopallium code in a lateralized way for learned visual cues. She could show further how the interactions in an asymmetrically wired visual system are organized. One of her reviewers, Prof. Vern Bingman, came all the way from Ohio to this event. The picture shows her during the party after her defence along with Onur and Vern Bingman.
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How different forms of anxiety-related personality traits affect basal ganglia-prefrontal networks
Anxiety is often associated with impaired cognitive control that gets manifest because basal ganglia-prefrontal circuits are compromised, especially in anxiety disorders. The aim of this study was to investigate the effect of anxiety-related personality traits, such as anxiety sensitivity and trait anxiety, on event-related potentials of response inhibition in a standard Go/Nogo-paradigm that reflect processes of basal ganglia prefrontal circuits. We focused on the Nogo-N2 and Nogo-P3 components, which probably represent different sub-processes of response inhibition. The Nogo-N2 was mainly influenced by trait anxiety, while it was slightly affected by anxiety sensitivity. In contrast, the Nogo-P3 was significantly associated with anxiety sensitivity, but was less affected by trait anxiety. Thus, anxious subjects seem to maintain a higher level of cognitive control to prepare and to monitor the outcome of their actions, which is differentially reflected in Nogo-N2 and Nogo-P3 potentials. Our results show that anxiety-related personality traits modulate electrophysiological responses related to cognitive control processes and should be taken into consideration in studies investigating response inhibition. The results show that different types of anxiety seem to differentially modulate basal ganglia-prefrontal circuits.
Sehlmeyer, C., Konrad, C., Zwitserlood, P., Arolt, V., Falkenstein, M. and Beste, C., ERP indices for response inhibition are related to anxiety-related personality traits, Neuropsychologia, 2010, 48: 2488-2495.
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Imaging of orientation representation in the pigeon’s visual Wulst
The pigeon is a widely established behavioral model of visual cognition, but the processes along its most basic visual pathways remain mostly unexplored. Now, Theoretical Neuroscientists and Biopsychologists from Bochum report the neuronal population dynamics of the visual Wulst, an assumed homolog of the mammalian primary visual cortex, captured for the first time with voltage-sensitive dye imaging. Responses to drifting gratings were characterized by focal emergence of activity that spread extensively across the entire Wulst, followed by rapid adaptation that was most effective in the surround. Using additional electrophysiological recordings, they found cells that prefer a variety of orientations. However, analysis of the imaged spatiotemporal activation patterns revealed no clustered orientation map-like arrangements as typically found in the primary visual cortices of many mammalian species. Instead, the vertical orientation was overrepresented, both in terms of the imaged population signal, as well as the number of neurons preferring the vertical orientation. Such enhanced selectivity for the vertical orientation may result from horizontal motion vectors that trigger adaptation to the extensive flow field input during flight and the fast head thrusts during walking. The findings suggest that, although the avian visual Wulst is homologous to the primary visual cortex in terms of its gross anatomical connectivity and topology, its detailed operation and internal organization is still shaped according to specific input characteristics.
Ng, B., Grabska-Barwinska, A., Güntürkün, O. and Jancke, D., Dominant vertical orientation processing without clustered maps: Early visual brain dynamics imaged with voltage-sensitive dye in the pigeon visual Wulst, J. Neurosci., 2010, 30: 6713-6725.
Prof. Dr. Dr. h.c. Onur Güntürkün
Onur Güntürkün was accepted as a new member to the Wilhelm-Wundt Gesellschaft. The Wilhelm-Wundt Gesellschaft is a scientific society that has limited the maximal number of its scholars to 30. Its goal is the promotion of basic knowledge in the field of experimental psychology as well as the promotion of young scientists.
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Learning of magnetic compass directions in pigeons
Pigeons are able to sense the magnetic field and use it to orient in space. However, a proof of magnetic compass learning by pigeons under laboratory conditions has been attempted for decades, but all experiments have failed so far. Now biopsychologists from Bochum and animal behavioral scientists from Frankfurt University aimed to test whether pigeons can learn magnetic compass directions in an operant chamber if magnetic cues are presented as true spatial cues. Experimental sessions were carried out in the local geomagnetic field and in magnetic fields with matched total intensity and inclination, but different directions generated with Helmholtz-coils. Birds demonstrated successful learning with a performance level comparable to that in learning studies with magnetic anomalies. Surprisingly, the most successful magnetic field learners in the lab were subsequently those that first took a detour in the field before flying to their loft. Did they first explore the territory before embarking on their voyage? In any way, these findings represent the first evidence for operant magnetic compass learning in pigeons and also provide a link between behavioural data from the field and the laboratory.
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Association between genetic variants of the metabotropic glutamate receptor 3 (GRM3) and cognitive set shifting in healthy individuals
The ability to adapt behaviour in a flexible way is a crucial cognitive function. Set-shifting and maintenance are complex cognitive processes, which are often impaired in several neuropsychiatric and neurodegenerative diseases. The genetic basis of these processes is poorly understood. We aimed to investigate the association between genetic variants of the metabotropic glutamate receptor 3 (GRM3) and cognitive set-shifting in healthy individuals. The relationship between 14 selected single nucleotide polymorphisms (SNPs) of the GRM3 gene and cognitive set-shifting as measured by perseverative errors using the modified card sorting test (MCST). Results show that SNP rs17676277 is related to the performance on the MCST. Subjects with the TT genotype showed significantly less perseverative errors as compared with the AA (P = 0.025) and AT (P = 0.0005) and combined AA/AT genotypes (P = 0.0005). Haplotype analyses suggest the involvement of various SNPs of the GRM3 gene in perseverative error processing in a dominant model of inheritance. The findings strongly suggest that the genetic variation (rs17676277 and three haplotypes) in the metabotropic GRM3 is related to cognitive setshifting in healthy individuals independent of working memory.
Baune, B.T., Suslow, T., Beste, C., Birosova, E., Domschke, K., Sehlmeyer, C., and Konrad, C. (2010), Association between genetic variants of the metabotropic glutamate receptor 3 (GRM3) and cognitive set shifting in healthy individuals, Genes, Brain and Behavior, 9: 459-466.
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Learning about dopamine by playing the shell game
For sure you know how difficult it is to track the correct shell in a shell game (German: “Hütchenspiel”). We have to fully attend to the correct object to not lose track of it. Selective attention is a crucial component of all sensory processing. Biopsychologists from Bochum tested the role of dopamine in attentional selection and in the maintenance of attention in pigeons. The birds were trained on a moving-dot paradigm comparable to the shell game and had to select a target among distractors and maintain attention to the target. Target and distractors consisted of white dots, moving at random on a touch-screen. Here you see a historic picture of the shell game along with a cartoon of three sequences of the experiment conducted with pigeons. In the pigeon-version of the shell game, the demand on attention was modulated by varying the number of distractors and the duration of motion. Both manipulations affected performance equally. In the next step, the contribution of dopamine to attention was investigated. Intracranial injections of D1-antagonist before testing led to decrements in performance that equally affected trials with different attentional demand. This drop in performance could not be attributed to altered motivation or motor performance. The conclusion was that dopamine has a critical role in attention. It is involved in the selection of targets for attention and in the stabilization of attention against interference. This is comparable to the role dopamine plays in working memory and argues for similar mechanisms underlying selective attention and working memory. For a video of the experiment, see below:
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LARGE ASSOCIATIVE BRAIN AREAS MAKE SMART BIRDS
Animals with a high rate of innovative and associative-based behaviour usually have large brains. New Caledonian (NC) crows stand out due to their tool manufacture, their generalized problem-solving abilities and an extremely high degree of encephalization. It is generally assumed that this increased brain size is due to the ability to process, associate and memorize diverse stimuli, thereby enhancing the propensity to invent new and complex behaviours in adaptive ways. However, this premise lacks firm empirical support since encephalization could also result from an increase of only perceptual and/or motor areas. Scientists from the Bochum Biopsychology lab, the University of Düsseldorf and the University of Auckland (New Zealand) now compared the brain structures of NC crows with those of other advanced birds. The brains of NC crows were characterized by a relatively large association and motor-learning areas. This supports the hypothesis that the evolution of innovative or complex behaviour requires a brain composition that increases the ability to associate and memorize diverse stimuli in order to execute complex motor output. Since apes show a similar correlation of cerebral growth and cognitive abilities, the evolution of advanced cognitive skills appears to have evolved independently in birds and mammals but with a similar neural orchestration.
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A new genetic window into functional specialisations of basal ganglia circuits
The basal ganglia are connected to prefrontal cortical areas via different functional loops. These loops do not only differ with respect to their cognitive functions the mediate, but also on a neurochemical level. In the current study we ask, how these differences on a neurobiochemical level may affect cognitive processes mediated by these loops. One function of the anterior-cingulate loop is error processing. One function of the orbito-frontal loop is response inhibition. Combining a genetic approach with event-related potential (ERP) measurements of response inhibition (OFC-loop function) and error processing (ACC-loop function), we provide robust results showing a selective modulation of response inhibition processes by the GRIN2B C2664T polymorphism at the behavioural and neurophysiological level. Since error processing functions were not affected, the results suggest for differential influences of the GRIN2B C2664T polymorphism on response inhibition and error processing functions. The results provide first insight into cognitive-neurophysiological effects of the GRIN2B C2664T polymorphism. The dissociation obtained may be due to a differential importance of N-methyl-d-aspartate receptors for glutamatergic neural transmission in different striatal compartments (matrix and striosomes). We provide a model on this that may be a target for future research.
Beste, C., Baune, B. T., Domschke, K., Falkenstein, M., & Konrad, C., Dissociable influences of NR2B-receptor related neural transmission on functions of distinct associative basal ganglia circuits, NeuroImage, 2010, 52: 309-315.
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Biological and social causes for sex differences in parking
The stereotype of women’s limited parking skills is deeply anchored in modern culture. When entering the items ‘women’ and ‘parking’ in one of the biggest search engines of the World Wide Web, more than 80.000.000 results are obtained. As parking is a complex, spatial task, and a large body of literature proves the existence of sex differences in spatial cognition in favour of men, it is possible that the prejudice addressing women’s poor parking skills has a scientific background. To test this possibility, we investigated parking performance of 17 driving beginners and 48 more experienced drivers in an area of a car park that was closed off for the public. Subjects conducted three different types of manoeuvres (forward, backward, parallel), which were analysed for speed and accuracy. We found that men park more accurately and especially faster than women. On average, males were 42 seconds faster and 3 % more accurate than women. Although overall performance was better in experienced drivers, the sex difference remained. Performance was related to spatial skills and self-assessment in driving beginners, but only to self-assessment in more experienced drivers. As male subjects outperformed females in the mental rotation test for spatial skills and achieved higher scores in the self-assessment questionnaire, we assume that the sex difference in parking is due to these two variables. We assume that – due to differential feedback – self-assessment incrementally replaces the controlling influence of spatial skills, as parking is trained with increasing experience. Additionally, the prevalence of the prejudice about women’s parking skills could constitute a stereotype threat that additionally decreases women’s performance. Our results suggest that sex differences in spatial cognition found in laboratory experiments persist in real-life situations. However, real-life spatial cognition is also influenced by socio-psychological factors, which modulate the biological causes of sex differences.
Wolf, C.C., Ocklenburg, S., Ören, B., Becker, C., Hofstätter, A., Bös, C., Popken, M., Thorstensen, T. & Güntürkün, O., Sex differences in parking are affected by biological and social factors, Psych. Res., 2010, 74: 429-435.
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Looming responses of telencephalic neurons in the pigeon are modulated by optic flow
The movement of animals through space filled with various objects requires the interaction between neuronal mechanisms specialized for processing local object motion and those specialized for processing optic flow generated by self-motion of the animal. In the avian brain, visual nuclei in the tectofugal pathway are primarily involved in the detection of object motion. By contrast, the nucleus of the basal optic root (nBOR) and the pretectal nucleus lentiformis mesencephali (nLM) are dedicated to the analysis of optic flow. But little is known about how these two systems interact. Using single-unit recording in the entopallium of the tectofugal pathway, we show that some neurons appeared to be integrating visual information of looming objects and whole field motion simulating optic flow. They specifically responded to looming objects, but their looming responses were modulated by optic flow. Optic flow in the nasotemporal direction, typically produced by the forward movement of the bird, only mildly inhibited the looming responses. Furthermore, these neurons started firing later than when the looming object was presented against a stationary background. However, optic flow in other directions, especially the temporonasal direction, strongly inhibited their looming responses. Previous studies have implicated looming-sensitive neurons in predator avoidance behavior and these results suggest that a bird in motion may need less time to initiate an avoidance response to an approaching object.
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When things go wrong – error processing and the serotonergic system
Behavioural adaptation and cognitive control are crucial for goal-reaching behaviour. Common sense suggests that errors are an important source of information in the regulation of such processes. Much effort is undertaken to understand the neurobiological mechanisms underlying these processes. Several lines of research suggest that the serotonergic system may be of special interest in this respect.
This study investigates the dependence of response monitoring and error detection on genetic influences modulating the serotonergic system, which was done using the event-related potentials (ERPs) after error (Ne/ERN) and correct trials (Nc/CRN). To induce a sufficient amount of errors, a standard flanker task was used. The subjects (N = 94) were genotyped for the functional 5-HT1A C(-1019)G polymorphism. In order to investigate neural processes that are specific for error monitoring, time-frequency analyses (wavelet-analyses) were applied. The results show that the 5-HT1A C(-1019)G polymorphism specifically modulates error detection. Neurophysiological modulations on error detection were paralleled by a similar modulation of response slowing after an error, reflecting the behavioral adaptation. The 5-HT1A -1019 CC genotype group showed a larger Ne and stronger post-error slowing than the CG and GG genotype groups. More general processes of performance monitoring, as reflected in the Nc/CRN, were not affected. The finding that error-specific processes, but not general response monitoring processes, are modulated by the 5-HT1A C(-1019)G polymorphism is underlined by a wavelet analysis. In summary, the results suggest a specific effect of the 5-HT1A C(-1019)G polymorphism on error monitoring processes and suggest a neurobiological dissociation between processes of error monitoring and general response monitoring at the level of the serotonin 1A receptor system.
Beste, C., Domschke, K., Kolev, V., Yordanova, J., Baffa, A., Falkenstein, M., & Konrad, C., Functional 5-HT1a receptor polymorphism selectively modulates error-specific subprocesses of performance monitoring, Hum Brain Mapp, 2010, 31: 621-630.
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Linking attention, eye-movements and working memory using the serotonergic system
Numerous lines of research indicate that attentional processes, working memory and saccadic processes are highly interrelated. Even though this relation has often been postulated in literature, the neurobiological mechanism underlying this interrelation, are not understood. In the current study, we examine the relation between these processes with respect to their cognitive-neurophysiological and neurobiological background by means of event-related potentials (ERPs) in a sample of N = 72 healthy probands characterized for the functional serotonin receptor 1 A (5-HT1A) C(−1019)G polymorphism. The results support a close interrelation between working memory, attentional and saccadic processes. Yet, these processes are differentially modulated by the 5-HT1A C(−1019)G polymorphism. The 5-HT1A C(−1019)G polymorphism primarily affects attentional processing, whereas processes related to the mental rotation of an object are independent of 5-HT1A genetic variation. It is shown that an increasing number of −1019 G alleles leads to a differential reduction of the N1 above the left and right hemisphere and hence bottom-up attentional processing. In the way increasing numbers of −1019 G alleles lead to a reduction of attentional processes, saccadic activity increases as a similar function of the number of −1019 G alleles. This increase in activity occurs parallel in time to the process of mental rotation. It is hypothesized that decreased attentional processes, dependent on different 5-HT1A C(−1019)G genotypes, may cause parietal networks to increase saccadic activity in order to perform mental rotation. The results support theories of highly interlinked attention, working memory and eye-movement systems.
Beste, C., Heil, M., Domschke, K., & Konrad, C., The relevance of the functional 5-HT1A receptor polymorphism for attention and working memory processes during mental rotation of characters, Neuropsychologia, 2010, 48: 1248-1254.
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Learning of Magnetic Compass Direction in Pigeons
How does it feel to sense the magnetic field? How is it to actually "see" where North is? We humans do not know how it feels to sense the magnetic compass but we can study the mechanisms of this system in birds. Previous studies had shown that birds can "visualize" the magnetic compass directions and, in addition, can sense the strength of the local magnetic field. However, all attempts to actually train birds to learn a compass direction had failed. A new study by scientists from Frankfurt, Düsseldorf and the Biopsychology Department in Bochum now reports the first successful study on learning the magnetic compass direction. Pigeons were trained in an operant chamber with magnetic compass directions as true spatial cues. Experimental sessions were carried out in the local geomagnetic field and in magnetic fields with matched total intensity and inclination, but divergent directions generated with Helmholtz-coils. The animals successfully learned to peck those keys that were in the direction of the correct compass direction. Subsequently, the birds were tested in a true outdoor homing task. Astonishingly, the more successful individuals of the Skinner-Box learning experiment had worse initial orientations at unfamiliar, but not at familiar sites. The authors speculate that the better learners might have more self confidence to first explore unknown locations before taking the way back home. Future studies will show if this interpretation is correct.
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How the serotonergic system modulates our selection of appropriate responses
Response selection and control are supposed to reflect important basal ganglia functions. Recently, we showed that the dopaminergic system may be especially important for response selection in compatible, but not in incompatible stimulus-response (S-R) relations. Research indicates that the dopaminergic system is influenced by the serotonergic system, but little is known about the involvement of the serotonergic system in response selection. Analyzing event-related potentials (ERPs) we show the 5-HT1A C(-1019)G polymorphism modulating response-related processes, but only in compatible S-R relations. This modulation was a function of the number of -1019 G alleles. Decreasing numbers of -1019 G alleles were stepwise related to increases in response selection efforts. The functional effect of the 5-HT1A C(-1019)G polymorphism has previously been shown to be specific for serotonergic 1 A autoreceptors of serotonergic neurons in the dorsal raphe nucleus (DRN). Due to this close relation of genotype effects to neuroanatomically dissociable structures, the results suggest that DRN serotonin 1 A autoreceptors are important for response selection. The results extend previous findings on the dopaminergic system to the serotonergic system. The examined functions are precisely regulated on a neuronal level, since neurophysiological and behavioural effects are driven in an allele-dose fashion. Because of this, the results are of importance for future clinical applications.
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Tuning perceptual competition
The way our brain selects relevant information and discards irrelevant one is a highly competitive process. The ability to notice relevant visual information has been assumed to be determined both by the relative salience of relevant information compared with distracters within a given display and by voluntary allocation of attention toward intended goals. A dominance of either of these two mechanisms in stimulus processing has been claimed by different theories. A central question in this context is to what degree and how task irrelevant signals can influence processing of target information. This question was examined in this study using event-related potentials (ERPs). Using parametrical manipulations of the saliency of distracting stimuli we found that the amount of saliency was predictive for the proportion of detected information when relevant and irrelevant information were spatially separated but not when they overlapped. Weighting and competition of incoming signals was reflected in the amplitude of the N1pc component of the event-related potential. Initial orientation of attention toward the irrelevant element had to be followed by a reallocation process, reflected in an N2pc. The control of conflicting information additionally evoked a fronto-central N2 that varied with the amount of competition induced. Thus the data support models that assume that attention is a dynamic interplay of bottom-up and top-down processes that may be mediated via a common dynamic neural network.
Tobias Ohmann successfully fulfilled his defence on the 9th of February 2010 in the Faculty of Psychology and was awarded with a Dr. rer. nat. Tobias truly impressed the committee and the spectators (the room was filled to the last place) with a brilliant overview of his work and a smooth and highly informed discussion. In his thesis, Tobias had studied the behavioural neuroscience of time – a highly elusive property of life. His experiments reached from waiting for reward or punishment up to episodic-like recall of the last time-of-meal and incorporated highly ingenious behavioural approaches.
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How different dopaminergic pathways affect different subprocesses of inhibiting a response
Response inhibition is a component of executive functions, which can be divided into distinct subprocesses by means of event-related potentials (ERPs). These subprocesses are (pre)-motor inhibition and inhibition monitoring, which are probably reflected by distinct ERP-components. We asked, if these subprocesses may depend on distinct basal ganglia subsystems. We examined response inhibition processes in an extended sample of young and elderly subjects, patients with Parkinson’s disease (PD) and Huntington’ disease (HD). This combination of groups also allow us to study whether, and to what degree, pathological basal ganglia changes and healthy aging have similar and/or different effects on these processes. Indeed subprocesses of response inhibition are differentially modulated by distinct basal ganglia circuits. Processes related to (pre)-motor inhibition appear to be modulated by the nigrostriatal system, and are sensitive to aging and age-related basal ganglia diseases (i.e. PD). Parkinson’s disease induces additive effects of aging and pathology. In contrast, inhibition monitoring is most likely modulated by the mesocortico-limbic dopamine system. These processes are equally affected in healthy aging and both basal ganglia diseases (i.e. PD, HD).
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How risk alleles for basal ganglia dysfunctions confer an advantage for specific executive functions
Response inhibition is a basic executive function which is dysfunctional in various basal ganglia diseases. The brain-derived-neurotrophic-factor (BDNF) plays an important pathophysiological role in these diseases. In the current study we examined the functional relevance of the BDNF val66met polymorphism for response inhibition processes in 57 healthy human subjects using event-related potentials (ERPs), which likely reflect different aspects of inhibition. The results show that the BDNF val66met polymorphism selectively modulates the pre-motor subprocesses of response inhibition. Response inhibition was better in the val/met-met/met group, since this group committed fewer false alarms, and their Nogo-N2 was larger, compared to the val/val group. This is the first study showing that met alleles of the BDNF val66met polymorphism confer an advantage for a specific cognitive function. We propose a neuronal model how this advantage gets manifest on a neuronal level.
Beste, C., Baune, B. T., Domschke, K., Falkenstein, M., & Konrad, C., Paradoxical association of the brain-derived-neurotrophic factor val66met genotype with response inhibition, Neuroscience, 2010, 166: 178-184.
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The relevance of subcortical structures vs. cortical structures for pain perception – an fMRI study
Peripheral and central mechanisms of pain from incision differs from inflammatory or chronic pain. It is expected that brain activation patterns differ with pain type but have not been studied in humans. In this study, the activation of different brain areas after an experimental surgical incision was assessed by functional magnetic resonance imaging, and the pathophysiological role of distinct brain activation patterns for pain perception after incision was analyzed. Functional magnetic resonance imaging analysis showed a distinct temporal profile of activity within specific brain regions during and after the injury. Lateralization (predominantly contralateral to the incision) and increased brain activity of the somatosensory cortex, frontal cortex, and limbic system were observed in subjects after incision, when compared with individuals receiving sham procedure. Peak brain activation occurred about 2 min after incision and decreased subsequently. Basal ganglia structures and especially the caudate nucleus were activated shortly after incision. Lateron activity persists in neocortical structures, but was absent in basal ganglia structures. A distinct correlation between evoked pain ratings and brain activity was observed for the anterior cingulate cortex, insular cortex, thalamus, frontal cortex, and somatosensory cortex. These findings show different and distinct cortical and subcortical activation patterns over a relevant time period after incision. Pain sensitivity hereby has an influence on the activity profile. This may have important implications for encoding ongoing pain after a tissue injury, for example, resting pain in postoperative patients.
Pogatzki-Zahn, E.M., Wagner, C., Meinhardt-Renner, A., Burgmer, M., Beste, C., Zahn, P. K., & Pfleiderer, B., Coding of incisional pain in the brain: a functional magnetic resonance imaging study in human volunteers, Anesthesiology, 2010, 112: 406-417.
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How handedness affects auditory space perception
Several studies have shown that handedness has an impact on visual spatial abilities. However, the relationship of handedness and spatial processing in the auditory modality has remained largely unclear. To investigate this relationship, scientist from Durham University (England), the Ifado in Dortmund and the Ruhr-University of Bochum assessed auditory space perception in left- and right-handers in a dark, anechoic, and sound-proof room. Interestingly, participants showed a bias in sound localization that was to the side contralateral to the preferred hand. This partially parallels findings in the visual modality as left-handers typically have a more rightward bias in visual line bisection compared with right-handers. Despite the differences in neural processing of auditory and visual spatial information these findings show similar effects of lateral preference on auditory and visual spatial perception. This suggests that supramodal neural processes are involved in the mechanisms generating laterality in space perception.
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How visual experience affects handedness
Most theories of human handedness assume that it is completely determined by genetic factors. However, since there is a large body of evidence for an influence of non-genetic factors on asymmetries in other vertebrates, biopsychologist from Bochum tested the hypothesis that human handedness may also result from a combination of genetic and experience-driven factors. In order to do so, the research team analysed sidedness in children suffering from congenital muscular torticollis. These children display a permanently tilted asymmetric head posture to the left or to the right in combination with a contralateral rotation of face and chin, which could lead to an increased visual experience of the hand contralateral to the head-tilt. Relative to controls, torticollis children had a higher probability of right- or left-handedness when having a head-tilt to the opposite side. Thus, an increased visual control of the hand during early childhood seems to modulate handedness. These findings not only show that human handedness is affected by early lateralised visual experience but also speak in favour of a combined gene-environment model for its development.
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Reading a pigeon’s mind
Cicero (106-43 B.C.) is quoted as saying, 'Ut imago est animi voltus sic indices oculi' (the face is a picture of the mind as the eyes are its interpreter). Today we use this original quote in the slightly abbreviated form as “the eyes are the window to the soul”. Indeed, countless eye-tracking studies have uncovered hidden intentions and hot spots of attention by observing the eye movements of human volunteers. Unfortunately, bird researchers were until recently excluded from this rich source of knowledge since it is impossible to comparably track eye movements of birds. Now, scientists from the Biopsychology laboratory in Bochum invented a fast way to track the peck locations of pigeons while these animals discriminated hundreds of photographs that contained humans or just landscapes and other objects. Peck location tracking is an indirect way to trace the foci of attention of pigeons. Once this method was established, the scientists were up to a surprise: The birds specifically pecked onto the humans in the pictures. Thus, they attended to the critical portion of the pictures and aimed at these areas. But even more than that: the animals focused on the heads of humans. When these heads were cut out, discrimination success of the birds dropped significantly. So, reading a pigeon’s mind reveals that for them it is our face that makes us human.
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A method for the evaluation of intracranial tetrodotoxin injections
Tetrodotoxin, the poison of the buffer fish, is often used by neuroscientists to selectively block specific brain regions. In spite of this abundant use, little was known about the temporal and spatial decay of TTX injected in brain tissue. Scientists of the Biopsychology group have now been able to develop an immunohistochemical protocol to make injected TTX visible on brain slices. With this approach they could show that the diffusion of TTX one hour after injection to pigeons' entopallium was 3 mm in all directions. Furthermore, contrary to the often assumed decay period of maximally 24 h, they showed that only after 48 hours TTX had completely cleared from the brain tissue. With this new approach the spread of injected TTX can easily be visualized and therefore it makes the blocking of specific brain regions more reliable.
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Pigeons identify individual humans but show no sign of recognizing them in photographs
It seems to be so easy to recognize a person on a photograph. In fact, it’s quite difficult: First of all, we have to transform a 3D-human to a 2D-image. We also have to accept that the absolute size of the two objects is vastly different, that the human moves around while the picture is static, etc. Despite these and many more problems, we easily generalize from humans to pictures and vice versa. But are other animals also able to do it? This is an important question since hundreds of publications with pigeons rely on the implicit assumption that photographs do represent real objects for these birds. Biopsychologists from Bochum, from the Max-Planck-Institute for Biological Cybernetics in Tübingen and from Mugla University (Turkey) tested the ability of pigeons to perform the transfer from 3D-individual humans to 2D-pictures of these individuals. Sixteen birds were first trained to identify individual, real-life humans. It turned out that this discrimination depended primarily on visual cues from the heads of the persons. Subsequently, the pigeons were shown photographs of these individuals to test for transfer to a two dimensional representation. Successful identification of a three-dimensional person did not facilitate learning of the corresponding photographs. These results show that the cross-recognition of individual real-life humans and their photographs in pigeons is far more limited than previously assumed.
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Vison During Head-Bobbing: The Rise and Fall of a Scientific Explanation
Have you ever watched a pigeon walking? The head constantly seems to thrust foreward and backward while the rest of body behaves as if being a wind up toy. Scientists know since long that the fore-and-back oscillation of the head is just an illusion: In reality the head quickly thrusts foreward but subsequently stands still while the body moves. Then the head thrusts foreward again, etc. Thus, there is no backward movement of the head. But why is the movement of the head different from the rest of the body? Well, here comes a clever explanation: If the head would move constantly together with the body, the retinal image would be blurred due to movement artefacts. So, a quick foreward thrust (during which the animal should be blind mostly), followed by hold period should be an optimal solution. This explanation was so compelling that it was accepted by almost everybody for decades. Now scientists from Spain, Canada, and Biopsychologists from the Ruhr-University have killed this theory (requiescat in pace as the Romans would say). With a true high-tech approach they managed to flash patterns onto monitors while the pigeons were either just thrusting their head foreward, or were just in their hold phase. To do so, head movements were tracked by means of an optical motion capture system consisting of high-speed cameras which provided the three-dimensional position of a marker mounted on the head of the animal in real time. The job of the pigeons was simple: Tell me which pattern was shown to you. The results were also simple: The pigeons were equally able to perfectly perform the discrimination both in the thrust and in the hold phase. Thus, head-bobbing can not be explained by a temporary blindness during the movement time of the head. Now that the temporary-blindness-theory is dead, what then is the explanation for head bobbing? Well, more research is needed…
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Dual coding of visual asymmetries in the pigeon brain
You read this paragraph by mostly using resources of your left hemisphere. But is the asymmetry of your brain realized at the neuronal level and how does it emerge during your lifetime? The pigeon’s visual system is an excellent model to find answers for these questions. Now, Biopsychologists from Bochum have published a review on 20 years of asymmetry research in this model. They describe how lateralized visual stimulation induces structural asymmetries within the brain of the embryo during a critical time window, and how these early asymmetrical signals shape the nervous system into a lateralized structure. Interhemispheric control mechanisms seem to stabilize these induced asymmetries. The functional left-right differences are then established due to the interplay between bottom-up and top-down mechanisms that generate a lateralized, hemispheric-specific visual analysis.
Lars Dittrich successfully graduated on the 29th of October in the IGSN and was awarded with a PhD of Neuroscience. Lars impressed the committee so much that they unanimously decided to grade his thesis and defence with a summa cum laude – a rare and very prestigious event. Lars analyzed how pigeons learn a complex categorization task in which the animals have to come up with a strategy to discriminate humans from non-humans on pictures. In addition he introduced novel ways to "read a pigeons mind" with behavioural and anatomical means. Subsequent to the party, Lars' students gave him a shisha as present. As shown below, the new device was directly put into widespread use.
Teaching Award for Maik Stüttgen
Maik Stüttgen received a teaching award from the students of the Graduate School for Neural and Behavioural Sciences. During the winter term 2009, he lectured on 'Essential Statistics' for students of neuroscience at the University of Tübingen. The curriculum covered a range of topics including probability theory, correlation & regression, null-hypothesis statistical testing, effect sizes and confidence intervals.
Blockseminar "Klinische Prüfung von Wirkstoffen"
Das Blockseminar "Klinische Prüfung von Wirkstoffen" (114 291) von Prof. See wird am 18. und 19.02.2010 sowie am 25. und 26.02.2010 jeweils von 10-16:30 Uhr im Raum GAFO 05/609 stattfinden. Die Vorbesprechung zu der Veranstaltung findet am 23.11.2009 von 18 s.t.-19 Uhr ebenfalls im Raum GAFO 05/609 statt. Die Vorbesprechnung ist verpflichtend für die Teilnahme an dem Seminar.
Vorlesung "Grundlagen der Neuro- und Sinnesphysiologie"
Die Vorlesung "Grundlagen der Neuro- und Sinnesphysiologie" von Frau Dr. Tagrid Yousef (B. Sc. Psychologie, 1. Semester) beginnt erst am Mittwoch, 04.11.2009, 10.00-12.00, HZO 20 (Anmeldung über VSPL).
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Biopsy-Team wins Psycho Cup 2009
This year 5 teams competed for the famous Psycho Cup. Besides Biopsychology, also Industrial Psychology, Neuropsychology, Clinical Psychology and the Psychology Workshop had sent their teams to win the fame and the glory that comes with the success in this traditional competition. The teams played against each other on the 25th of September under brilliant and sunny conditions. In a heart-throbbing final, the Biopsychology team outmatched its eternal enemy, the Psychology Workshop, 2 to 1. The picture shows the heroes of the Cup Felix, Sivajan, Ali, Pascal, Tobias (team coach, holding the award), Joswin, and Cem.
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Asymmetries in quails retain a lifelong potential for plasticity
Japanese quail are an excellent model for studies on sexual behaviour. They very quickly learn to approach quails of the opposite sex when being reinforced with access to copulation. Previous studies had shown that quails tested with their left eye performed better than the ones tested with their right eye when working for sex. This right hemispheric dominance for instinctual and affective behaviour is typical for vertebrates, incl. humans. Now scientists from the Bochum Biopsychology lab and two universities in Izmir (Turkey) aimed to see if this hemispheric dominance can be modified by asymmetrical light input in early life. To this end they closed the right or the left eyes of the 2 day-old quail for 70 days and tested the subjects in the same set up. Indeed, asymmetry of behaviour had disappeared. Thus, brain asymmetries can be altered with asymmetrical sensory stimulation in early life. However, the scientist were up for a surprise when they removed the eye cap from the closed eye, switched its position to the previously open eye and retested the birds. Suddenly, the old right hemispheric dominancy emerged again. So, the old left-right differences had survived in the deprived hemisphere, showing that lateralized circuits are retained to some extent, even after major changes on the undeprived side.
Das menschliche Gehirn - ein Mal- und Bastelkurs
In January 2008 the seminar "Das menschliche Gehirn - ein Mal- und Bastelkurs" (The human brain - a painting- and craftsmanship course) of the Biopsychology department was awarded on the conference "Kompetenzorientiert lehren und lernen an der RUB" for exemplary teaching.
As a result this film was made to show the concept and the realization of the seminar to a broad community.
If you enjoyed it please distribute the web location to people who might be interested in it.