[Contribution of the electrophysiological study of sleep in psychiatry (author's transl)].

The authors briefly remind us of physiological characteristics of normal sleep and its modifications in psychiatric disorders. They draw attention to the numerous possibilities in the clinic of using electrophysiological sleep research. This is of importance in an area where few biological markers are available for the diagnosis and the treatment. Furthermore, sleep studies support the hypothesis of disturbances in circadian rhythms in affective disorders.