Séminaire de Vincent Hakim 29/11/2024

Vendredi 29 novembre 2024, 14h30 – Salle Henri Gastaud

Vincent Hakim (Département de Physique, Ecole Normale Supérieure) invited by Bjorg Kilavik

Internal architecture and external entries shape neuronal network dynamics: the case of beta oscillations in motor cortex

Abstract: Oscillatory activity with different characteristic frequencies is recorded in different neural areas. Bursts of beta (13-30Hz) oscillations are prominent in the motor cortex during movement preparation. Moreover, in several experiments, this oscillatory activity has been reported to organize into a variety of traveling wave types. I will discuss how these waves could arise in local excitatory-inhibitory modules coupled by long-range excitation. First, I will describe the synchronization properties of such a system that we reinvestigated following several previous works. I will then try to precisely compare the modeling to electrophysiological datasets recorded in the primary motor cortices of macaque monkeys during an instructed delayed reach-to-grasp task. Close agreement between the model and the experimental data is obtained in the presence of stochastic entries that have both spatially local and global components and mimic inputs to the motor cortex from other neural areas. The results suggest that both time-varying external entries and intrinsic network architecture shape the dynamics of the motor cortex.