[Neurophysiological and clinical aspects of psychophysiological insomnia].

Nowadays, a high percentage of the population in modern societies suffers from various kinds of sleep disturbances, in part due to the impact of increased socio-cultural stress factors. The most common sleep complaint is insomnia. Psychophysiological insomnia is one of the most frequent forms of sleep disturbances. It is a type of conditioned or learned insomnia that is presumably derived from two sources. The first involves the conditioning of sleep-preventing habits in which repeated pairing of sleeplessness and situational, temporal, or behavioural stimuli normally associated with sleep leads to conditional arousal that impairs sleep. The second involves somatised tension believed to result from the internalisation of psychological conflicts and excessive worrying about sleep, which are incompatible with sleep. Quantitative EEG approach, particularly with spectral analysis, has recently refined the analysis of the EEG in sleep. These EEG quantification techniques are now very useful to understand the neurophysiological basis of a lot of sleep disorders, particularly in the case of psychophysiological insomnia.