有界噪声激励下神经系统中反随机共振现象研究

Inverse Stochastic Resonance in Neural System Induced by Bounded Noise

为了考察噪声对神经元系统中内部信息传递的作用,研究了有界噪声对神经元放电行为的影响,特别是噪声对神经元放电的抑制效应即反随机共振现象.通过蒙特卡洛随机模拟方法,系统研究了当输入电流激发神经元持续放电的情况下,有界噪声中各参数对神经元平均放电率的影响.研究发现,随机相位能抑制神经元的放电行为,即产生反随机共振现象;振幅越大,频率越小,抑制效果越明显;且在稳定的振幅和频率条件下,电流强度越小,平均放电率越小,抑制效果越明显.该抑制效应的研究对生物医学疾病如癫痫具有重要的理论意义.

In order to study the effect of noise on the information transmission in neural system, firing of neural system driven by the bounded noise was discussed, especially the inhibitory effect of neuron firing, which was called the phenomenon of inverse stochastic resonance. Through the stochastic simulation method of Monte Carlo, the influence of parameters of bounded noise on the average spiking rate was systemic studied when the neurons were in the continuous firing state under the input current. Investigation results indicate that random phase can restrain neural spiking and induce the phenomenon of inverse stochastic resonance. Meantime, the bigger the amplitude is, and the smaller the frequency is, the better of the inhibition on the neural spiking is. In addition, the smaller the current intensity is, the smaller the average spiking rate is and it is means that the inhibition effect is more distinct. The research of inhibitory effect gives an important theoretical significance on the treatment of medical diseases such as epilepsy.