How ‘REM sleep’ is paradoxical in human
H. Bastuji
Neurophysiologie Clinique January 8, 2018 DOI: 10.1016/j.neucli.2018.06.008 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Peer reviewed |
|---|---|
| Key findings | Argues that during paradoxical sleep, thalamo-cortical activity is decoupled and mid-anterior cingulate responses to nociceptive stimuli are suppressed while sensory processing persists, and that verbal discordance detection operates differently than in waking. The authors propose these differences may account for absurd dream content, hypnagogic hallucinations in narcolepsy, and the incorporation or neglect of painful stimuli without awakening. |
Abstract
Although brain activity has some similarity during paradoxical sleep and wakefulness, it differs in many aspects. Thalamic and cortical activities, time-locked throughout wakefulness and slow wave sleep, are different during paradoxical sleep, that of the thalamus being in the delta range while that of the cortex being rapid. This decoupling of thalamo-cortical activity may participate to phenomena such as altered experience during dream or hypnagogic hallucinations in narcolepsy. Detection of verbal discordance is preserved during PS, but with a different process that of waking, responses to pseudo-words being similar to those to congruous words. Linguistic absurdity appears to be accepted in a different manner during paradoxical sleep than during waking, and this might explain why absurd contents are so naturally incorporated into otherwise plausible dream stories. In responses to nociceptive stimuli, while the lateral operculo-insular system subserving sensory analysis of the stimuli remained active during paradoxical sleep, mid-anterior cingulate processes related to orienting and avoidance behavior are suppressed. Dissociation between sensory and orienting-motor networks might explain why nociceptive stimuli can be either neglected or incorporated into dreams without awakening the subject.