局部耦合的双层忆阻神经元网络的嵌合态和同步

嵌合态被发现存在于神经系统并且可能在神经元节律、大脑的睡眠和记忆等诸多神经过程中发挥重要作用.本文考虑神经元交互中的电磁感应现象,建立了以Hindmarsh Rose神经元为节点的局部耦合的双层忆阻神经元网络,研究其嵌合态时空动力学模式及产生机理.结果发现,改变层内、层间突触耦合强度会使网络产生移动和不完美移动嵌合态等多种类型的嵌合模式,其中不完美移动嵌合态中不相干的区域会扩展到网络的相干域.特别地,在特定耦合强度下,存在一种新的嵌合态活动模式,即一部分神经元处于嵌合态,另一部分神经元处于移动嵌合态.考虑神经元突触的忆阻特性,发现忆阻参数的增加能够使处于嵌合态的神经元网络转变为同步态,且耦合强度越大,达到同步态所需要的忆阻参数值越小.进一步探究双层网络的同步性,发现层间耦合强度和忆阻参数的增大有助于网络达到更好的同步.研究结果表明神经元之间的相互作用可以激发双层神经元网络产生多种嵌合态模式,电磁感应可以促进网络由嵌合态向同步态转迁,这些结果有助于理解人脑中复杂的神经放电过程和信息处理机制,并为可能的类脑装置应用提供参考.

Chemira States and Stnchronization in A Two Layer Locally Coupled Memristive Hindmarsh Rose Neuronal Network

Chimera states have been found in nervous systems and may play an important role in many neural processes including neuronal rhythms, sleep and memory in the brain. Considering the phenomenon of electromagnetic induction in the neuron interactions, a two-layer memristive neuronal network of locally coupled Hindmarsh-Rose neurons was established to study the spatiotemporal dynamical patterns of chimera states and the mechanisms of their generation. It is found that changing the intra- and inter-layer synaptic coupling strengths can induce several types of chimera states in networks, including traveling and imperfect traveling chimera states where the incoherent traveling domain spreads into the coherent domain of the network. In particular, a phenomenon that several neurons are in chimera states and others are in traveling chimera states is witnessed at specific coupling strengths. Moreover, it is also observed that increasing the memristive parameter can induce the neuronal network to change from chimera states to synchronous states, and the stronger the coupling strengths, the smaller the value of the memristive parameter required to reach synchronous states. Considering the inter-layer synchronization, the increase of the coupling strengths and the memristive parameter helps the network to achieve better synchronisation. The results demonstrate that the interactions between neurons on two-layer neuronal networks can stimulate a variety of patterns of chimera states, and that the effect of electromagnetic induction can facilitate the transition from chimera states to coherent states. These results are useful for understanding the complex neural firing processes and information processing mechanisms in the human brain and may provide a reference for the application of the brain-like devices.