RESUMO
Objective To investigate the phenomenon of coherence resonance(CR)in a nonlinear integrate-and-fire neuronal model(NIF)induced with correlated voltage-gated channel noise and synaptic noise.Meanwhile,the effects of intensity of the voltage-gated channel noise,intensity of the synaptic noise and the strength of the correlation between noises on coherence resonance are discussed.Methods Based on the adiabatic approximation theory and the two-state theory,the approximate expressions of the probability distribution of neuron first fire(FPD)and the coefficient of variation(CV)of the inter-spike intervals of neuron discharging were obtained.Results It was shown that the FPD and the CV were the function of intensities of the voltage-gated channel noise,intensities of the synaptic noise and the strength of the correlation between noises.Conclusion By choosing appropriate the intensity of noise and the strength of the correlation between noises,the minimum of the CV can be obtained,to make the maximum coherence of system and the phenomenon of coherence resonance will occur.