3rd FUNDING PERIOD

THEMATIC AREA B: MULTI-SITE INTERACTIONS DURING DEVELOPMENT, PLASTICITY AND LEARNING

Prof. Dr. Ileana L. Hanganu-Opatz

Dept. of Neuroanatomy, UKE  

Prefrontal-hippocampal dysfunction is considered as main cause of cognitive deficits in mental disorders, yet its ontogeny and mechanisms throughout life are still largely unknown. Using mouse models that mimic the etiology and symptoms of schizophrenia, we showed during the first two funding periods that, shortly after birth, the long-range coupling between prefrontal cortex and hippocampus is reduced due to structural and functional deficits of specific neuronal populations. Preliminary data identified juvenile age as an additional period of high vulnerability for disease. Here, we will elucidate the cellular substrate of juvenile prefrontal-hippocampal miswiring leading to poorer cognitive performance and identify electrophysiological markers of dysfunction common to mice and prodromal humans.

Dr. Fabio Morellini

Behavioral Biology Unit, ZMNH, UKE

Prof. Dr. Thomas Oertner

Dept. of Synaptic Physiology, ZMNH, UKE  

We use optogenetic and electrophysiological approaches to investigate how specific neuronal populations encode spatial memories. By activity-dependent expression of optogenetic silencers, we are able to shut off mossy cells that were highly active during encoding of a specific spatial location and test the effects on water maze performance. As we could show, learning of a new location typically re-activates dentate gyrus neurons encoding for the old location. We will investigate the importance of this reactivation for successful reversal learning and monitor learning-induced connectivity changes between the left and right hemisphere.

Prof. Dr.  Simon Wiegert

Research Group Synaptic Wiring and Information Processing, ZMNH, UKE

Institute for Synaptic Physiology, ZMNH, UKE

How does the brain know what it has to remember and what it may safely forget? Dopamine is a central neuromodulator signaling salience and novelty and it is important for learning and memory formation. In this project we will investigate how dopamine controls network activity and functional connectivity in the dorsal hippocampus of mice during different behavioral states. Using two-photon imaging in the hippocampus during behavior in combination with optogenetic and chemogenetic manipulation of locus coeruleus and ventral tegmental area we aim at unravelling the specific roles of these long-range projecting areas for defined behavioral states and hippocampus-dependent learning and memory-formation.

Prof. Dr. Lars Schwabe

This project aims at elucidating the impact of stress and major stress mediators on memory reconsolidation and the underlying brain networks. We predict that stress and glucocorticoid activation impair reconsolidation by interfering with the recruitment of and crosstalk in limbic, prefrontal and large-scale frontoparietal memory networks, whereas noradrenergic stimulation may have the opposite effect. In order to test these predictions, we will combine experimental stress-induction and pharmacological elevation of glucocorticoid and noradrenergic activity with funtional MRI recordings of memory network dynamics during encoding, reactivation and test.

Prof. Dr. Brigitte Röder

The present study will test two hypotheses in human visual and multisensory neural networks: (1) The development of top-down communication lags behind the development of bottom-up processing; (2) the development of top-down processing depends to a larger extent on early sensory experience than the development of bottom-up processing. Two EEG paradigms, a visual attention and a multisensory paradigm, will be developed in human adults. They will consecutively be adapted to children (5-11 year old, prospective developmental approach) and sight-recovery individuals (retrospective developmental approach) to test these two hypotheses, respectively.