Sleep disturbances in affective disorders

Sleep disturbances are an integral feature of affective disorders. Episodes of affective illness are often accompanied by marked changes in sleep. Insomnia frequently occurs in mania, and insomnia or hypersomnia often occurs in depression. The observation that sleep deprivation improves mood in about 50-60%of depressed subjects [1], and that it can even trigger mania in patients with bipolar disorder [2, 3], suggests a close relationship between the regulation of mood and the regulation of sleep. If we assume a neurobiological link between sleep and mood, the recent explosion of basic findings on the functional neuroanatomy of sleep-wake regulation and on the cellular basis of the different sleep rhythms [4-7] should open newways in our understanding of affective disorders. In the present review, we therefore propose to focus primarily on those findings that enable the integration of sleep-wake electrophysiological and neurobiological data observed in affective disorders with our present knowledge of the sleep-wake mechanisms.SCOPUS: ch.b