If the brain is critical, what is the phase transition?

Thursday, May 16, 2013 - 3:00pm - 4:00pm
Regents 109
Mauro Copelli
Department of Physics, Federal University of Pernambuco, Recife, Brazil

Neuronal avalanches were experimentally observed a decade ago, lending support to a long-held conjecture that the brain as a dynamical system might be operating near a second-order phase transition. Nontrivial statistics, such as power law distributions and other scale-invariant properties, have been the essential connection between the theory of critical phenomena and neurophysiological data. Many models which have been used to simulate neuronal collective behavior share common features, displaying a phase transition from an absorbing (quiescent) to an active (but otherwise unstructured) phase. Most of these belong to the directed percolation universality class, which has served as a theoretical workhorse in the field. I will discuss the strength and limitations of this theoretical framework in light of experimental results, as well as alternatives arising from different models.

Host: Rhonda Dzakpasu