Stochastic resonance in spatially extended systems: the role of far from equilibrium potentials

Previous works have shown numerically that the response of a “stochastic resonator” is enhanced as a consequence of spatial coupling. Also, similar results have been obtained in a reaction–diffusion model by studying the phenomenon of stochastic resonance (SR) in spatially extended systems using nonequilibrium potential (NEP) techniques. The knowledge of the NEP for such systems allows us to determine the probability for the decay of the metastable extended states, and approximate expressions for the correlation function and the signal-to-noise ratio. Here, exploiting known forms of the NEP, we have investigated the role of NEP's symmetry on SR, the enhancement of the SNR due to a selectivity of the coupling or diffusion parameter, and discussed competition between local and nonlocal (excitatory) coupling.