Neurodynamic behavior of hippocampal CA1 neuron model driven by external current stimulation

Abstract

Electromagnetic intervention has significant superiorities in improving the brain cognitive functions. The hippocampal CA1 neuron is associated with cognitive functions such as working memory and spatial navigation. However, it is difficult to capture the neurodynamic behavior of biological neurons due to the disadvantages of biological electrophysiological signals. Neuron model can simulate the electrophysiological characteristics of biological neuron, and produce its neurodynamic behavior. In addition, the hippocampal CA1 neuron model did not consider the electromagnetic induction caused by ions flow inside and outside the cell membrane of biological neurons. Thus, introducing magnetic flux-controlled memristor, we construct a hippocampal CA1 neuron model that considers electromagnetic induction. Then, we investigate its neurodynamic behavior driven by external current stimulation using neurodynamic methods, including the interspike interval bifurcation, the largest Lyapunov exponent, the time sequence of membrane potential, and the phase diagram. Our results find that when the CA1 neuron model is initially in any of the resting state, spiking state, and cluster-firing state, the model’s firing is promoted as the amplitude of external current stimulation increases, while the model’s firing is inhibited as the frequency of external current stimulation increases. Additionally, as the amplitude increases, the model exhibits different firing modes, tending to chaotic firing from the three initial states; as the frequency increases, the model exhibits different firing modes, tending to spiking or cluster-firing from the three initial states. This work can enhance the understanding of the regulatory mechanism of external current stimulation on the hippocampus.