电磁辐射下神经元放电模式及其环状耦合同步研究

Firing patterns and synchronous transition of ring-coupled neurons under electromagnetic radiation

摘要:

鉴于外部磁场会对神经元放电活动产生影响，讨论了具有磁场作用的四变量ML(Morris and Lecar)神经元模型，利用快慢动力学揭示了其簇放电类型及分岔过程,并分析了随磁通反馈系数变化时系统放电行为. 同时以三个环状耦合神经元模型为例，通过定义同步判断标准——互相关系数和快慢变量的极大同步差，发现耦合神经元在磁场作用下，很小的耦合强度就可使系统从混沌状态转迁到周期放电模式并能诱导神经元完成从互不相关到簇放电同步再到峰放电同步的转迁. 且在合适的双参数范围内，适当耦合强度下系统更容易实现同步，有助于理解在适当耦合连接方式下电磁辐射对神经网络集群放电活动的影响及其同步机理.

Abstract:

In view of the external magnetic field having an impact on the discharge activity of neurons, a four variable ML(Morris and Lecar) neuron model with magnetic field is discussed. The bursting type and bifurcation process are revealed by using fast/slow dynamical bifurcation analysis, and discharge behavior of the system with the change of flux feedback coefficient is studied. At the same time, taking the three coupled neuron models with ring connections as an example, by defining the synchronization criterion—correlation coefficient and the maximum synchronization difference of fast and slow variables, it is found that under the action of magnetic field, a very small coupling strength can make a system transform chaos state into periodic discharge mode, and induce the synchronous transition of neuron from unrelated to burst synchronization, then to spike synchronization. Within the appropriate dual parameter range, the system is easier to synchronize with the appropriate coupling strength. It is helpful to understand the influence of electromagnetic radiation on the collective discharge motion of neural network and its synchronization mechanism under the proper coupling connections mode.