Physiological responses of men during sleep deprivation.

The effects of 84 hours of sleep deprivation were examined in a group of six young men and compared with a group of six controls. Subjects were studied in pairs, one sleep-deprived and one control. Primary attention was given to the responses to acute whole body cold exposure in terms of internal body and skin temperature changes, oxygen consumption changes and plasma catecholamine levels. Psychomotor performance was evaluated at 4-hour intervals over the course of the sleepless period and the patterns of urinary excretion of catecholamines, magnesium, and creatinine were followed. the first sleepless night, psychomotor performance of sleep-deprived subjects was significantly lower than that of control subjects. The ability to regulate body temperature during standardized cold exposures, however, was not impaired by the loss of sleep. Urinary excretion patterns for the two groups were similar, except for differences related to activity level. is suggested that, despite the gross psychomotor changes observed during sleep deprivation, physiological regulating systems are relatively unaffected by sleep loss.