准周期噪声激励FHN神经元模型引起的动力学特征

Dynamic characteristics of the FitzHugh-Nagumo neuron model induced by quasi-monochromatic noise

目的:在FHN模型上,研究Bursting放电的特征,观察Bursting放电发生的机制,观察准周期噪声(quasi-monochromaticnoise,QMN)引起的Bursting放电形式,研究与实际真实神经元放电的噪声特性。方法:观察试验数据和数学模型产生的放电形式差异,采用功率谱分析、信噪比、放电间期的概率密度、一致性程度等分析。结果:阈下膜电位振荡不是完全单一频率组成的波形,而是由一个狭窄频率范围的信号组成,而QMN信号具有与实际阈下膜电位振荡非常相近的频率特征和波形,所产生的放电与实际神经元的放电类似。在合适的噪声条件下,信噪比最高;放电具有相位同步的特征。结论:QMN是一种较好的模拟Bursting放电的刺激条件。

AIM:To study the discharging characteristics of Bursting in the basis of FitzHugh-Nagumo(FHN) neuron model induced by quasi-monochromatic noise(QMN) so as to explore the noise characteristics of the discharge of actual neurons.METHODS:By comparing and analyzing the power spectral densities,signal-to-noise ratios,degree of coherences of test data and FHN model,the characteristics of bursting were studied.RESULTS:Sub-threshold membrane potential oscillation(SMPO) was not a mono-frequency signal,but it was a QMN signal,which had similar frequent features and wave form to the actual SMPO.The frequency of SMPO was in a narrow frequency range.The signal-to-noise reached the highest in the proper intensity of noise.Interspike interval(ISIH) presented the characteristics of phase locked. CONCLUSION:QMN is a good tool to study bursting discharge.