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arXiv · 1405.6232

Quasi-Critical Brain Dynamics on a Non-Equilibrium Widom Line

Rashid V. Williams-Garcia·Mark Moore·John M. Beggs·Gerardo Ortiz
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Abstract

Is the brain really operating at a critical point? We study the non-equilibrium properties of a neural network which models the dynamics of the neocortex and argue for optimal quasi-critical dynamics on the Widom line where the correlation length is maximal. We simulate the network and introduce an analytical mean-field approximation, characterize the non-equilibrium phase transition, and present a non-equilibrium phase diagram, which shows that in addition to an ordered and disordered phase, the system exhibits a quasiperiodic phase corresponding to synchronous activity in simulations which may be related to the pathological synchronization associated with epilepsy.

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Rashid V. Williams-Garcia, Mark Moore, John M. Beggs, Gerardo Ortiz. 2014-05-23. Quasi-Critical Brain Dynamics on a Non-Equilibrium Widom Line. https://doi.org/10.1103/physreve.90.062714

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