Polysomnographic comparison between patients with primary alcohol dependency during subacute withdrawal and patients with a major depression.

Complex neurobiological models based on animal research have been formulated in an attempt to explain the cyclic pattern of nonREM and REM sleep. The "reciprocal interaction model" of nonREM and REM sleep regulation, which has been updated to incorporate new evidence is still the most convincing. Therefore it is reasonable to apply this model also to REM sleep abnormalities such as shortened REM latency and increased REM density, observed in patients with depression and alcohol dependency.