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This article is part of the supplement: Sixteenth Annual Computational Neuroscience Meeting: CNS*2007

Open Access Poster presentation

Physics of psychophysics: optimal dynamic range of critical excitable networks

Mauro Copelli1* and Osame Kinouchi2

Author Affiliations

1 Laboratório de Física Teórica e Computacional, Departamento de Física, Universidade Federal de Pernambuco, 50670-901, Recife, PE, Brazil

2 Departamento de Física e Matemática, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brazil

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BMC Neuroscience 2007, 8(Suppl 2):P174  doi:10.1186/1471-2202-8-S2-P174

The electronic version of this article is the complete one and can be found online at:

Published:6 July 2007

© 2007 Copelli and Kinouchi; licensee BioMed Central Ltd.

Poster presentation

A recurrent idea in the study of complex systems is that optimal information processing is to be found near phase transitions [1-3]. However, this heuristic hypothesis has few (if any) concrete realizations where a standard and biologically relevant quantity is optimized at criticality. Here we give a clear example of such phenomenon: a network of excitable elements has its sensitivity and dynamic range maximized at the critical point of a nonequilibrium phase transition. Our results are compatible with the essential role of gap junctions in olfactory glomeruli and retinal ganglion cell output. Synchronization and global oscillations also emerge from the network dynamics. We propose that the main functional role of electrical coupling is to provide an enhancement of dynamic range, therefore allowing the coding of information spanning several orders of magnitude. The mechanism provides a microscopic neural basis for psychophysical laws.


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