Steyn-Ross D A, Steyn-Ross Moira L, Sleigh J W, Wilson M T, Gillies I P, Wright J J
Department of Physics & Electronic Engineering, University of Waikato, New Zealand.
J Biol Phys. 2005 Dec;31(3-4):547-69. doi: 10.1007/s10867-005-1285-2.
We present a mean-field model of the cortex that attempts to describe the gross changes in brain electrical activity for the cycles of natural sleep. We incorporate within the model two major sleep modulatory effects: slow changes in both synaptic efficiency and in neuron resting voltage caused by the ∼90-min cycling in acetylcholine, together with even slower changes in resting voltage caused by gradual elimination during sleep of somnogens (fatigue agents) such as adenosine. We argue that the change from slow-wave sleep (SWS) to rapid-eye-movement (REM) sleep can be understood as a first-order phase transition from a low-firing, coherent state to a high-firing, desychronized cortical state. We show that the model predictions for changes in EEG power, spectral distribution, and correlation time at the SWS-to-REM transition are consistent not only with those observed in clinical recordings of a sleeping human subject, but also with the on-cortex EEG patterns recently reported by Destexhe et al. [J. Neurosci.19(11), (1999) 4595-4608] for the sleeping cat.
我们提出了一种皮层平均场模型，该模型试图描述自然睡眠周期中大脑电活动的总体变化。我们在模型中纳入了两种主要的睡眠调节效应：由乙酰胆碱约90分钟的循环引起的突触效率和神经元静息电压的缓慢变化，以及由睡眠期间诸如腺苷等促眠物质（疲劳因子）的逐渐消除引起的静息电压更缓慢的变化。我们认为，从慢波睡眠（SWS）到快速眼动（REM）睡眠的转变可以理解为从低发放、相干状态到高发放、去同步化皮层状态的一级相变。我们表明，该模型对SWS到REM转变时脑电图功率、频谱分布和相关时间变化的预测不仅与睡眠人类受试者临床记录中观察到的结果一致，而且与德斯特克斯等人[《神经科学杂志》19(11)，(1999)4595 - 4608]最近报道的睡眠猫的皮层脑电图模式一致。
