Title: Introduction to connectivity.
Session: Whole-brain, Connectome-based Models of Brain Dynamics: From Principles to Applications
Speaker: Joana Cabral
Abstract: The dynamics of networked systems is known to be strongly dependent on topological features of the connectivity map, particularly when the system operates at the critical border between incoherence and full synchrony. The map of neuroanatomical connections between brain areas obtained from diffusion imaging thus plays a crucial role not only in mediating the transmission of neural signals between brain areas but actually in shaping brain activity in space and time. Computational models simulating the interactions between neural signals in the connectome serve as powerful tools to investigate the impact of specific connectome properties, such as its distribution of coupling weights and distances, as well as properties defined from graph theory, on the resulting dynamics. In this lecture I will demonstrate how the brain connectome has features that support non-stationary dynamics driven by transient cluster synchronization. I will demonstrate how altering the connectome structure by removing nodes or links or reorganizing the distribution of links can greatly disrupt the stability of this critical regime. In addition, I will demonstrate how considering the distance between brain areas introduces an additional degree of complexity that expands the dynamics in the frequency domain, supported by the literature in the physics of delay coupled systems. Scripts for the simulation of brain dynamics using distinct variations of the connectome structure will be made available and a short demonstration will be performed at the end of the talk.
