Many patients, especially those with psychiatric disorders, complain o
f disturbed sleep. Thus the question arises whether there is a link be
tween disturbed sleep and psychic complaints. In this article the foll
owing aspects are critically reviewed: 1. impact of sleep changes on t
he pathogenesis of psychiatric disorders; 2. onset of sleep disturbanc
es in correlation to onset of psychiatric symptomatology; 3. specifici
ty of sleep patterns in psychiatric syndromes; 4. therapeutical conseq
uences due to the findings of sleep EEG studies. Up to now the sleep d
ata of psychiatric patients in the literature are rather inconsistent.
Furthermore there are only a few rather specific findings. Some impor
tant clinical aspects for the planning of therapeutic strategies are r
eviewed.