The common treatment modalities for depression, i.e. pharmacotherapy and psychotherapy have the significant disadvantage of at least a three- to four-week time lag between initiation of treatment and amelioration of mood. Total sleep deprivation (TSD) in contrast, leads to an immediate antidepressant effect in 60% of the patients. However, it has gained only little clinical relevance as usually the improvement is only transient and almost regularly reversed by the next nights of sleep. A procedure preserving the antidepressive effect of sleep deprivation would therefore be of high clinical relevance.
