高频信号作用于神经元的仿真研究

The Effects of High Frequency Signal Investigated in a Neuron Model

高频电磁辐射对神经系统有负面影响,并且此类生物实验特别是人体实验会引起潜在的健康危害,而在数学模型中的仿真研究则可以完全避免。通过随机龙格库塔算法求解含有白噪声的Hodgkin-Huxley神经元模型,研究了高频信号对神经元的影响。实验结果表明神经元模型处于其最敏感频率环境中时,随着高频信号的幅频比的提高,模型会产生放电频率下降,随机共振消失等现象,噪声强度较强时还产生了振动共振现象,而且神经元的静息电位也将被高频振荡代替。放电现象消失与生理实验发现的高频电流信号可以阻断外周神经动作电位的传导结果一致,本研究还有助于非电离辐射引起的体内特别是神经系统的损伤的预防和治疗,以及神经系统的模型仿真及其信号处理机制的研究。

We have investigated the effects of high frequency （HF） signal on firing activity in a biologically realistic system--the noisy Hodgkin-Huxley （HH） neuron model via numerical simulations. The results show that when the HF amplitude to frequency ratio （AFR） increases, the firing rate is diminished and stochastic resonance disappears, even the HH neuron model is processing a stimulus of its most sensitive frequency. When the noise intensity is strong, the vibration resonance can be observed. Moreover, the fluctuation around the resting potential will be replaced by an oscillation of the same high frequency with the increasing AFR. The inhibition of the firing activity is consistent with the results of experiment in vivo that HF current can stop the transmission of action potential in peripheral nerve. This study is of functional significance to the biomedical research on the damages caused by electropollution in vivo and signal processing.