Multistability in coupled Fitzhugh-Nagumo oscillators

We consider a pair of neurons modelled by Fitzhugh-Nagumo equations with el ectrical coupling. When the neurons are identical, we show how the symmetry of the system leads to the coexistence multiple, stable periodic orbits. A s the coupling between the neurons is strengthened, these periodic orbits c an undergo various bifurcations, leading to the coexistence of multiple, st able chaotic attractors. We show that this behaviour persists for near-iden tical neurons.