Temperature-modulated synchronization transition in coupled neuronal oscillators.

We study two firing properties to characterize the activities of a neuron: frequency-current (f-I) curves and phase response curves (PRCs), with variation in the intrinsic temperature scaling parameter (μ) controlling the opening and closing of ionic channels. We show a peak of the firing frequency for small μ in a class I neuron with the I value immediately after the saddle-node bifurcation, which is entirely different from previous experimental reports as well as model studies. The PRC takes a type II form on a logarithmic f-I curve when μ is small. Then, we analyze the synchronization phenomena in a two-neuron network using the phase-reduction method. We find common μ-dependent transition and bifurcation of synchronizations, regardless of the values of I. Such results give us helpful insight into synchronizations tuned with a sinusoidal-wave temperature modulation on neurons.