Masuda Naoki, Aihara Kazuyuki
Department of Mathematical Engineering and Information Physics, Graduate School of Engineering, the University of Tokyo, 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan.
Phys Rev Lett. 2002 Jun 17;88(24):248101. doi: 10.1103/PhysRevLett.88.248101. Epub 2002 May 30.
It is controversial whether temporal spike coding or rate coding is dominant in the information processing of the brain. We show by a two-layered neural network model with noise that, when noise is small, cortical neurons fire synchronously and intervals of synchronous firing robustly encode the signal information, but that the neurons desynchronize with moderately strong noise to encode waveforms of the signal more accurately. Further increase of noise just deteriorates the encoding. A positive role of noise in the brain is suggested in a meaning different from stochastic resonance, coherence resonance, and deterministic chaos.
在大脑的信息处理中,是时间脉冲编码还是速率编码占主导地位存在争议。我们通过一个带有噪声的两层神经网络模型表明,当噪声较小时,皮层神经元同步放电,同步放电的间隔稳健地编码信号信息,但当噪声强度适中时,神经元会去同步化以更准确地编码信号波形。噪声进一步增加只会使编码恶化。噪声在大脑中的积极作用与随机共振、相干共振和确定性混沌的意义不同。