The effect of sleep deprivation on depressed patients.

In this paper an account is given of the effect of single-night sleep deprivation (SD) therapy in 124 depressive patients of different diagnostic groups. Phasic depressives showed a marked improvement after treatment by sleep deprivation. Because these improvements were often of short duration, we repeated the treatments and combined them with thymoleptic drugs. In the group of neurotic depressives the therapeutic effect of sleep deprivation varied; on the whole, however, the improvement was less marked. It is pointed out that the vital symptoms and "critical time" are of importance. Sleep deprivation can be explained as a resynchronization of disturbed circadian rhythms brought about by interrupting these rhythms.