Li Li, Zhao Zhiguo
Guangdong Key Laboratory of Modern Control Technology, Institute of Intelligent Manufacturing, Guangdong Academy of Sciences, Guangzhou 510070, China.
School of Science, Henan Institute of Technology, Xinxiang 453003, China.
Phys Rev E. 2022 Mar;105(3-1):034408. doi: 10.1103/PhysRevE.105.034408.
Coherence resonance (CR) describes a counterintuitive phenomenon in which the optimal oscillatory responses in nonlinear systems are shaped by a suitable noise amplitude. This phenomenon has been observed in neural systems. In this research, the generation of double coherence resonances (DCRs) due to white noise is investigated in a three-dimensional reduced Hodgkin-Huxley neuron model with multiple-timescale feature. We show that additive white noise can induce DCRs from the resting state near a subcritical Hopf bifurcation. The appearance of DCRs is related to the changes of the firing pattern aroused by the increases of the noise amplitude. The underlying dynamical mechanisms for the appearance of the DCRs and the changes of the firing pattern are interpreted using the phase space analysis and the dynamics of the stable focus-node near the subcritical Hopf bifurcation. We find that the multiple-timescale dynamics is essential for generating the DCRs and different firing patterns. The results not only present a case in which noise can induce DCRs near a Hopf bifurcation but also provide its dynamical mechanism, which enriches the phenomena in nonlinear dynamics and provides further understanding on the roles of noise in neural systems with multiple-timescale feature.
相干共振（CR）描述了一种违反直觉的现象，即非线性系统中的最优振荡响应是由合适的噪声幅度塑造的。这种现象已在神经系统中被观察到。在本研究中，我们在具有多时间尺度特征的三维简化霍奇金-赫胥黎神经元模型中研究了由白噪声引起的双相干共振（DCR）的产生。我们表明，加性白噪声可以在亚临界霍普夫分岔附近从静止状态诱导出DCR。DCR的出现与噪声幅度增加引起的放电模式变化有关。使用相空间分析和亚临界霍普夫分岔附近稳定焦点-节点的动力学来解释DCR出现和放电模式变化的潜在动力学机制。我们发现多时间尺度动力学对于产生DCR和不同的放电模式至关重要。这些结果不仅展示了噪声可以在霍普夫分岔附近诱导DCR的情况，还提供了其动力学机制，丰富了非线性动力学中的现象，并为噪声在具有多时间尺度特征的神经系统中的作用提供了进一步的理解。
