Dr. Arvind Kumar, Bernstein Center Freiburg, Neurobiology and Biophysics, Faculty of Biology, University of Freiburg, Germany
Basal ganglia (BG) play a crucial role in several motor and cognitive function. Accordingly, chemical or structural changes in one or more of BG nuclei result in major brain disorders like Parkinsonís disease, Huntingtonís disease etc. The dynamical signatures of the brain diseases that involve BG dysfunction are manifested at level of changes in the dynamical states of neuronal activity in one or more BG nuclei.
In my talk I will describe the recent progress in modelling and understanding the origin of various dynamical states within the striatum, the main input stage of the BG. I will show that the inhibitory connectivity within the striatum gives rise to a threshold like function. Although the threshold function of the striatum determined by the recurrent connectivity, it can be modulated by several components of the BG hardware and chemistry, to represent the behavioral state, learning history and motivation level of the animal.
Our models provide novel insights about the brain diseases that involve the BG. For instance, PD can be understood as a change in operative point in the striatum instead of a bifurcation in the sub thalamic nucleus and globus pallidus networks, as is commonly assumed. Finally, I will discuss how such computational models of brain diseases could help us develop novel therapeutic measures.