The significance of different sleep stages for the regulation of electrical brain activity in man.

In 9 patients with implanted electrodes, the relationships between 13 deep subcortical structures and the premotor cortex were considered during different sleep stages, using both neuronal activities and slow electrical processes (including scalp EEG). Changes occurred asynchronously with a relative independence between the various brain structures during slow sleep. On the other hand, during REM sleep, all parameters reveal a high degree of synchronization of the activities. It is suggested that during slow wave sleep each of the separate rhythms display their own regulation, while in paradoxical sleep, it is their inter-relationships which are mainly controlled. The REM stage probably has some other function, associated with the fact that a neuronal population which has taken no part in any activity during wakefulness now reacts.