局部扩散功能缺陷对随机神经元网络时空斑图的影响  

THE EFFECT OF LOCAL DEFECT WITHOUT DIFFUSION FUNCTION ON SPATIOTEMPORAL PATTERNS OF RANDOM NEURAL NETWORK

作　　者：刘少宝[1,2] 吴莹[1] 郝忠文[2] 李银军[2] 贾宁[2] 

机构地区：[1]西安交通大学航天航空学院机械结构强度与振动国家重点实验室,西安710049 [2]西安理工大学土木建筑工程学院工程力学系,西安710048

出　　处：《动力学与控制学报》2012年第1期81-87,共7页Journal of Dynamics and Control

基　　金：国家自然科学基金资助项目(10972179;10872155;10602003)~~

摘　　要：采用Hodgkin-Huxley神经元模型,在二维随机神经网络中引入局部扩散功能缺陷,研究了神经网络中非对称缺陷附近的方形失去扩散功能的缺陷对螺旋波动力学行为的影响.缺陷使螺旋波降低传播速度的行为与缺陷的位置和尺寸有关:靠近螺旋波中心的缺陷影响最为显著,当缺陷远离中心位置时,缺陷的作用明显减弱;缺陷尺寸越大,影响也越显著.同时观察到,在弱耦合神经网络中,缺陷的存在导致了螺旋波的漂移现象.进一步研究缺陷和通道噪声同时存在时系统时空斑图的演化行为,结果发现,噪声作用下缺陷处形成了新的波源.最后,通过分析神经元放电节律和平均膜电位的变化揭示了缺陷对神经网络时空行为影响的机理.The effects of the position and size of local defects without diffusion function on patterns of two-dimen- sional random neural network were investigated by using the Hodgkin-Huxley model. The result shows that the spiral wave becomes more scattered when the size of defect gets bigger,significantly near to the center of the spiral waves,which means the defect impact is correlated with the defect size positively. Furthermore,it is found that the drift phenomenon of spiral wave is induced by defect in weakly coupled neural network. Study on the behavior of spatiotemporal patterns with the coexistence of channel noise and defect shows that the new wave source is made by the effect of noise. Finally,the physical mechanisms for these phenomena were briefly discussed by analyzing the discharge frequency and the mean membrane voltage of neurons.

关 键 词：神经元网络 缺陷 通道噪声 时空斑图 

分 类 号：O415[理学—理论物理]