Sustained performance with short evening and morning sleeps.

The effect which early evening sleep may have on overnight and subsequent daytime performance, and the effect which morning sleep may have on daytime performance after overnight sleep deprivation has been studied in six healthy male volunteers. It would appear that relatively short periods of natural and drug induced (brotizolam 0.125 mg) sleep have a beneficial effect on subsequent performance even in the absence of preceding sleep debt. In the event of disturbed sleep in shiftwork an hypnotic may be helpful, and in this context, one which is rapidly eliminated and sustains sleep is appropriate.