Stochastic Resonance with Sensitive Frequency Dependence in Globally Coupled Continuous Systems

A model of globally coupled bistable continuous systems with two series of cells, modeling competing processes between activators and suppressors, subject to periodic and stochastic forces is investigated. In the large system size limit the exact solution of linear response theory is obtained, which shows typical stochastic resonance (SR) behavior. In particular, we find a resonance, sensitively depending not only on noise intensity and coupling strength, but also on the frequency of the periodic forcing. The SR occurs at a noise-induced Hopf bifurcation point, and is associated with the divergence of linear response.