Rapid eye movement sleep in man: modulation by benzodiazepines.

The modulation of rapid eye movement REM sleep in man by benzodiazepines has been analysed using 366 sleep recordings with at least 3 REM periods, obtained in 25 individuals, over 9 years. Sleep-dependent and sleep-independent mechanisms are believed to control REM activity, and the effect of benzodiazepines can be explained if the sleep-dependent influence is modified. It is suggested that a negative feedback mechanism, which usually encourages the appearance of REM periods, is depressed, while a threshold and oscillator which determine the cyclical appearance of the activity, and its relation with the onset of sleep, are unaffected.