Description

Sleep is a naturally recurring state of reduced responsiveness to external stimuli, characterized by relative immobility, perceptual disengagement, and subdued consciousness, essential for physical and mental restoration. ORSleep is a reversible, periodic state where the body and brain are in a state of rest, distinct from wakefulness and coma. ORthe natural, easily reversible periodic state of many living things that is marked by the absence of wakefulness and by the loss of consciousness of one's surroundings, is accompanied by a typical body posture (such as lying down with the eyes closed), the occurrence of dreaming, and changes in brain activity