The classical biophysical Morris-Lecar model of neuronal excitability predicts that upon stimulation of the neuron with a sufficiently large constant depolarizing current there exists a finite interval of the current values where periodic spike generation occurs. Above the upper boundary of this interval, there is four-stage damping of the spike amplitude: 1) minor primary damping, which reflects a typical transient to stationary dynamic state, 2) plateau of nearly undamped periodic oscillations, 3) strong damping, and 4) reaching a constant asymptotic value of the neuron potential. We have shown that in the vicinity of the asymptote the Morris-Lecar equations can be reduced to the standard equation for exponentially damped harmonic oscillations. Importantly, all coefficients of this equation can be explicitly expressed through parameters of the original Morris-Lecar model, enabling direct comparison of the numerical and analytical solutions for the neuron potential dynamics at later stages of the spike amplitude damping.

神经元兴奋性的经典生物物理Morris-Lecar模型预测，当用足够大的恒定去极化电流刺激神经元时，电流值存在一定的间隔，在该间隔处会出现周期性的尖峰。在此区间的上限之上，有四个阶段的尖峰幅度阻尼：1）较小的初级阻尼，它反映了典型的从瞬态到平稳的动态状态； 2）几乎没有阻尼的周期性振荡的平稳期； 3）强阻尼；以及4）达到神经元电位的恒定渐近值。我们已经表明，在渐近线附近，Morris-Lecar方程可以简化为指数阻尼谐波振荡的标准方程。重要的，