Spatiotemporal stochastic resonance in a bistable FitzHugh-Nagumo ring with phase-repulsive coupling

In this paper, we numerically study a ring of bistable FitzHugh-Nagumo elements coupled in a phase-repulsive way, which are externally driven by a weak periodic signal and noises, and focus on the system's response. A novel type of spatiotemporal stochastic resonance of antiphase state is uncovered, namely, for an intermediate strength of individual noise, the elements can form an ... -upper-lower-upper-lower- ... antiphase structure along the ring, and the global activation oscillates nearly synchronously with the weak periodic signal. Meanwhile, the system response undergoes a resonant behavior with the intensity of noise. It is shown that the combinative effects of the periodic signal, noise, and coupling are of importance for its appearance. The influences of common and individual noises are also investigated.