Sleep Loss and Nap Effects on Sustained Continuous Performance

ABSTRACT Thirty young male volunteers participated in a study of sustained continuous performance using a variety of computer‐based tasks. After 6 hrs of recorded sleep, 10 subjects were assigned to perform continuously for 42 hrs without break. Three of these subjects were unable to complete the 42‐hr assignment, and 8 of the 10 suffered psychological events such as hallucinations and disorientation. Ten subjects permitted six 1‐hr naps over the 42 hrs performed more successfully than those allowed no sleep. Ten subjects permitted one 6‐hr rest period performed best of all. Fatigue effects appeared after 6 hrs. Time‐of‐day (circadian) effects were at times stronger than fatigue.