Dynamic range of hypercubic stochastic excitable media.
We study the response properties of d-dimensional hypercubic excitable networks to a stochastic stimulus. Each site, modeled either by a three-state stochastic susceptible-infected-recovered-susceptible system or by the probabilistic Greenberg-Hastings cellular automaton, is continuously and independently stimulated by an external Poisson rate h. The response function (mean density of active sites rho versus h) is obtained via simulations (for d=1,2,3,4) and mean-field approximations at the single-site and pair levels (for all d). In any dimension, the dynamic range and sensitivity of the response function are maximized precisely at the nonequilibrium phase transition to self-sustained activity, in agreement with a reasoning recently proposed. Moreover, the maximum dynamic range attained at a given dimension d is a decreasing function of d.
Assis
Vladimir R V
VR
Laboratório de Física Teórica e Computacional, Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil. vladimirassis@df.ufpe.br
Copelli
Mauro
M
D000200:Action Potentials / Q000502:physiology*; D000344:Afferent Pathways / Q000502:physiology*; D000818:Animals; D003198:Computer Simulation; D006801:Humans; D008959:Models, Neurological; D015233:Models, Statistical; D009415:Nerve Net / Q000502:physiology*; D009475:Neurons, Afferent / Q000502:physiology*; D012677:Sensation / Q000502:physiology*; D012684:Sensory Thresholds / Q000502:physiology; D013269:Stochastic Processes