Sleep-wake cycle, sleep-related disturbances, and sleep disorders: A chronobiological approach

There is convincing evidence that the functions of sleep include restoratio n of brain energy storage and memory consolidation. The circadian timing sy stem (CTS) is involved in the daily variation of almost any physiological a nd psychological variable evaluated thus far. Disturbances of the CTS can b e clinically observed by their influence on the sleep-wake cycle, hormones, body temperature, and locomotor activity. This article reviews the basic m echanisms of circadian rhythm sleep disturbances, names the applicable diag nostic tools and specific therapeutic strategies, and thereby hints at the impact of circadian rhythm sleep disturbance on psychiatric disorders, espe cially disorders of affect and cognition, in light of the preventive, diagn ostic, and therapeutic tools now available, a new round of chronobiological studies in psychiatry seems justified, promising, and necessary. Copyright (C) 2000 by W.B, Saunders Company.