噪声对皮层神经网络放电特性的影响

摘要

为研究噪声对皮层神经网络的影响,构建了基于脉冲时间依赖突触可塑性(spike timing dependent plasticity,STDP)调节机制的多层前馈皮层神经网络模型,发现在STDP突触机制的调节下,一定强度的噪声可以促进不同规模网络各层神经元的同步放电活动.仿真实验表明,神经元间连接概率不同时,促进网络同步放电的噪声强度也不同;网络各层神经元平均放电频率随着输入噪声强度的增强和连接概率的增大而增大,且噪声使网络各层的平均放电率波动减小,网络整体放电更加均匀,研究结果有助于认识大脑皮层神经网络的自适应特性.%To study the effects of noise on the cortical neural network, a feedforward spiking neural network with spike timing dependent plasticity (STDP) is constructed in this paper.It is found that under the regulation of STDP mechanism, noise could improve the spiking synchronization of the neurons in each layer of thenetworks of different sizes.The noise intensity needed to promote the network synchronization is different when the connection probability between adjacent layers neurons is different.The mean firing rate of the neurons in each layer of the networks is increased with the noise intensity and neuron connection probability.Moreover, the noise could reduce the volatility of the average firing rates of the layers in the network and make the overall firing of the network more uniform.The results will be helpful to recognize the self-adaptive ability of cortical neural network.