Lee S G, Kim S
Brain Research Center and Nonlinear and Complex Systems Laboratory, Department of Physics and Mathematics, Pohang University of Science and Technology, San 31 Hyojadong, Pohang 790-784, Korea.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 1999 Jul;60(1):826-30. doi: 10.1103/physreve.60.826.
Recently, the phenomena of stochastic resonance (SR) have attracted much attention in the studies of the excitable systems under inherent noise, in particular, nervous systems. We study SR in a stochastic Hodgkin-Huxley neuron under Ornstein-Uhlenbeck noise and periodic stimulus, focusing on the dependence of properties of SR on stimulus parameters. We find that the dependence of the critical forcing amplitude on the frequency of the periodic stimulus shows a bell-shaped structure with a minimum at the stimulus frequency, which is quite different from the monotonous dependence observed in the bistable system at a small frequency range. The frequency dependence of the critical forcing amplitude is explained in connection with the firing onset bifurcation curve of the Hodgkin-Huxley neuron in the deterministic situation. The optimal noise intensity for maximal amplification is also found to show a similar structure.
最近，随机共振（SR）现象在固有噪声下的可兴奋系统研究中，尤其是神经系统研究中，引起了广泛关注。我们研究了在奥恩斯坦-乌伦贝克噪声和周期性刺激下的随机霍奇金-赫胥黎神经元中的随机共振，重点关注随机共振特性对刺激参数的依赖性。我们发现，临界强迫幅度对周期性刺激频率的依赖性呈现出钟形结构，在刺激频率处有最小值，这与在小频率范围内双稳系统中观察到的单调依赖性有很大不同。结合确定性情况下霍奇金-赫胥黎神经元的放电起始分岔曲线，解释了临界强迫幅度的频率依赖性。还发现最大放大的最佳噪声强度也呈现出类似的结构。
