Bifurcation of modified HR neural model under direct current

On the basis of modified HR neuron model, this paper joins a depolarization direct current to investigate the dynamics of modified HR model under action of direct current with numerical computing method by adopting bifurcation diagram of inter-spike interval, the time responses diagram, the phase diagram and the two-parameter bifurcation diagram. These results indicate period adding bifurcation, period-doubling bifurcation as well as paroxysmal and intermittent chaos phenomenon in spiking neuron models can be observed clearly and intuitively, and not bifurcation structure of neuron model but ranges of parameters of various dynamic characteristics after adding direct current can be changed from the two-parameter bifurcation diagram.