A Study In Delay Coupled Neural Network

Neurons as the basic unit of the nervous system. It can feel the stimulation and conduction excitement. The transmission of nerve impulses in the neuron system often need to perform specific functions by way of coupling of neurons, Neuron system in the processing of information will be affected by noise, Neurons can generate spontaneous action potentials, due to noise. This article research from single neuron to neuronal network.First, considering a single neuron, In determined the HH model, It has been found that different intensity of external input current, neuron firing pattern is different. When external input current is greater than a critical value, the neuron can generate action potentials. In random HH model. Membrane size is finite, neurons without any external stimulation can generate spontaneous action potentials, due to stochastic opening and closing of sodium and potassium channels, Get the following result:(i). Neurons internal coherence resonance is caused by ion channel noise, there is an optimal membrane area reached a maximum coherence resonance.(ii). We found that with the increase of the membrane area, the average response time is increased.Second, the combined effect of transmission delay and channel fluctuations on popu-lation behaviors of an excitatory HH topology neural network. First, it is found that the network reaches a perfect spatial temporal coherence at a suitable membrane size. Such a coherence resonance is stimulus-free and is array-enhanced. Second, the presence of transmission delay can induce intermittent changes of the population dynamics. Besides, two resonant peaks of the population firing rate are observed as delay changes:one is at Td ≈ 7ms for all membrane areas, which reflects the resonance between the delayed interaction and the intrinsic period of channel kinetics; the other occurs when the trans-mission delay equals to the mean inter-spike intervals (ISIs) of the population firings in the absence of delay, which reflects the resonance between the delayed interaction and the intrinsic firing period of the non-delayed system. Third, Concerning the impact of network topology and population size, it is found that decreasing the connection proba-bility does not change the range of transmission delay but broadens the range of synaptic coupling that supports population neurons to generate action potentials synchronously and temporally coherently. Furthermore, there exists a critical connection probability that distinguishes the population dynamics into an asynchronous and synchronous state.Third, correlation poisson input effects on uncouple neuronal networks. In the only correlation poisson input, As the correlation increasing, the network synchronization, power spectrum are also gradually strengthen, To give a more systematic investigation of the combined effect of correlation input and channel noise on the population dynamics. When membrane area is small, poisson input and larger ion channel noise effects on neurons network can destroy the network dynamics. While, the membrane area is large, poisson input station leading role.