Bifurcations and excitability in the temperature-sensitive Morris–Lecar neuron

Abstract

The neuronal excitability related to the transition between firing and resting states is a basic and important dynamic behavior which has different bifurcation characteristics and spiking frequency responses. In this work, we study the response dynamics and the excitability of a Morris–Lecar neuron for two temperature-sensitive ion channels, calcium and leak current, respectively. The codimension-1 bifurcations and the frequency–response curves for different temperatures show that the neuronal excitability is from Class II to I with increasing temperature in the case of the temperature-sensitive calcium current but is from Class I to II for the case of the leak current. The further extensive codimension-2 bifurcations uncover that the neurons undergo different routes of the neuronal dynamics under increasing external current for different temperatures even the same neuronal excitability. These results provide insight into understanding the effect of temperature on the neuronal dynamics and response behaviors with the diversity of temperature-sensitive ion channels.