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SYPH: Physik im Hirn - Physical Approaches to Brain Function
SYPH 2: Physik im Hirn - Physical Approaches to Brain Function
SYPH 2.9: Poster
Thursday, March 14, 2002, 15:30–18:00, Poster D
Dynamics of Rate and Correlation in Cortical Feed-Forward Networks — •Tom Tetzlaff, Michael Buschermöhle, Theo Geisel, and Markus Diesmann — Dept. of Nonlinear Dynamics, MPI für Strömungsforschung, Göttingen
Experimental studies revealed that the cortical network can exhibit
spatio-temporal spike patterns associated with sensory or contextual
events (e.g. [1]). The concept of the synfire chain [2] explains how
a state can arise in which dynamically grouped neurons discharge in
precise coincidence. The excited mode of the underlying subnetwork is
characterized by volleys of spikes stably propagating from one neuron
group to the next [3]. In the ground state neurons asynchronously
fire at low rates. From here the excited synchronous regime can be
reached by increasing either firing rate or correlation inside the
chain. The divergent/convergent network structure causes a strong
coupling of both measures which can be captured in a 2-dimensional map
simultaneously describing the spatial dynamics of rate and
correlation. This framework enables us to discuss the stability of
the ground state.
[1] Prut et al. (1998) J. Neurophysiol. 79:2857–2874
Abeles M. (1991) Corticonics
Diesmann et al. (1999) Nature 402:529–533