Title:                  Chimera states and collective chaos in pulse-coupled neural networks

Speaker:            Simona Olmi, from Institute for Complex Systems-CNR, Florence Italy

Time:                 Thursday, 3^rd November, 2011, at 14:00

Place:                Room 1520-732           

Abstract:

We study the dynamics of two symmetrically coupled populations of identical leaky integrate-and-fire neurons characterized by an excitatory coupling. Upon varying the coupling strength, we find symmetry-breaking transitions that lead to the onset of various chimera states as well as to a new regime, where the two populations are characterized by a different degree of synchronization. Symmetric collective states of increasing dynamical complexity are also observed. The computation of the the finite-amplitude Lyapunov exponent allows us to establish the chaoticity of the (collective) dynamics in a finite region of the phase plane. The further numerical study of the standard Lyapunov spectrum reveals the presence of several positive exponents, indicating that the microscopic dynamics is high-dimensional.

Alberto Imparato

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