The response of excitable membrane models to a cyclic input

The response of a space-clamped patch of Hodgkin-Huxley membrane to an applied current density ofA cos(2ft)+BA/cm² is computed for frequencies from 5 to 250 Hz. The train of action potentials generated is phase-locked to the driving cycle,N action potentials occurring at fixed phases inM cycles. For frequencies whereN/M is a simple ratio a describing function for the membrane is computed. The phase-locked behaviour and describing functions are similar to those obtained for a simple leaky integrator neurone model.