Sleep deprivation (SD) is a common condition that afflicts many people in modern life. Restricted sleep time, particulary when chronic, may cause significant and cumulative neurobehavior deficits and physiological changes. Reduced sleep duration is associated with obesity, cardiovascular morbidity, traffic accidents and death. Many observations have revealed significant daytime cognitive dysfunction (state instability, reduced vigilance attention and working memory) after sleep restriction less than 7 hours per night.
Using neuroimaging technology (PET, functional MRI), impairment of glycose metabolism and neuronal activity in the frontal and temporal cortex and in the thalamus has been demonstrated after SD. Marked individual differences exist in individual cognitive vulnerability to sleep restriction. Current research findings regarding the effects of SD on neurobehavioral and physiological functioning suggest that adequate sleep duration (7–8 hours per night) is of crucial importance.