Cognitive processing during the transition to sleep

摘要

Dramatic physiological and behavioural changes occur during the transition from wakefulness to sleep. The process is regarded as a grey area of consciousness between attentive wakefulness and slow wave sleep. Although neurophysiological changes, as the emergence of EEG grapho-elements (spindles, K-complexes), changes in power spectra and coherence, thalamocortical connectivity in fMRI, and single neuron changes in firing patterns, have been well characterised during the falling asleep process, little attempt has been made to link these modifications to the cognitive and behavioural dynamics of the transition. We revise here the body and brain physiology, behaviour and phenomenology of these changes of consciousness and propose an experimental framework to integrate the two aspects of consciousness that interact in the transition, wakefulness and awareness.