Laboratoire Matière et Systèmes Complexes

Thèse de Tanguy Fardet effectuée sous la direction de Pascal Monceau, Samuel Bottani et Stéphane Métens.

Soutenance le mardi 18 septembre 2018 à 14h.

Lieu : bâtiment Condorcet, amphithéâtre Pierre-Gilles de Gennes (bâtiment Condorcet, niveau -1). La soutenance sera suivie d’un pot au 6e étage.

Growth and activity of neuronal cultures, emergence of organized behaviors

Abstract:

In this thesis, I provide models and numerical tools to better understand and predict the behavior and development of neuronal cultures and devices.

In particular, I detail a mechanism explaining the epileptiform bursts of activity which constitute the default behavior of neuronal cultures, and provide a concise theoretical formulation for this mechanism. This model enabled me to predict how various neuronal properties influence the collective dynamics, then to check experimentally that these predictions were indeed compatible with the behavior observed in vitro. I further develop this description in the second part of the thesis, where I analyze its spatiotemporal dynamics and the fact that burst nucleate in specific areas of neuronal networks.

Given the strong influence of the network structure on the activity which develops on it, I introduce a simulation platform to enable efficient modeling of the network development, accounting for the interactions between the neurons and their environment to simulate the entire growth process of neurons. The neurons generated by this software then enable us to create more realistic networks to describe neuronal cultures, as well as to reproduce more complex neuronal devices. Furthermore, preliminary results of neuronal activities sustained by these structures are compatible with experimental recordings.

Eventually, I discuss several future directions for which the use of neuronal devices would enable to circumvent current limitations of neuronal cultures, thus providing new information on the processes which underlie brain development and plasticity.