Julian Packheiser & Roland Pusch (Biopsychologie, RUB):
Neuronal properties of the the NCL during decision making
Monday, 04.05.2015, 1 - 3 pm, GAFO 05/425
Fakultät für Psychologie
Phone: +49 - 234 - 32 - 28213
Fax: +49 - 234 - 32 - 14377
News & Views
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!!
News & Views
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.
News & Views
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:
News & Views
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.
News & Views
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).