Quenched disorder-induced chaotic resonance: Optimal stimulus response near the edge of chaos

We study the collective stimulus response in two classical nonlinear dynamical models, the globally coupled bistable oscillators and the excitable FitzHugh-Nagumo neurons, where the coupling strength among the units are randomly distributed with fixed mean and varying variance. We find theoretically and numerically that in both models the ensemble response to a weak periodic stimulus exhibits a bell-shaped amplification manifesting a different type of resonance mechanism, namely, coupling-disorder-induced resonance, as the quenched disorder of coupling increases. Of particular interest is that the optimal collective response emerges near the orderchaos transition point, i.e., at the edge of chaos. As a promising application, we discuss briefly the potential reasonability for exploiting such a type of chaotic resonance to explain the optimal mutual information in the realistic inferior olive. Our results provide explicitly a clue that the disorderly coupled elements may utilize the coupling-disorder-induced chaos to optimize their stimulus response.