sleep deprivation [L, deprivare, to deprive; ME, slep + L, efficere, to accomplish] , the result of interference with a basic physiological urge to sleep, which appears to be governed by sleep centers in the hypothalamus and reticular activating system. Sleep deprivation can cause significant reductions in performance and alertness. Reducing nighttime sleep by as little as 90 minutes for just one night can affect cognitive processes. Sleep deprivation results in progressive mental aberrations after 30 to 60 continuous hours. After this point, repetitive tasks become intolerable, speech begins to be slurred, and performance becomes increasingly poor. After a week of sleep deprivation, symptoms of psychosis may appear.
