Research and theories of sleep

To talk about a concept, we must first be clear on its definition. Psychologists describe sleep as an altered state of consciousness. It is a resting state in which an individual becomes relatively quiescent and relatively unaware of the environment. During sleep, which is in part a period of rest and relaxation, most physiological functions such as body temperature, blood pressure, and rate of breathing and heartbeat decrease. The amount of sleep needed depends on …

…then it is the case that sleep has all these functions and more that we do not know about yet. The bottom line is that sleep is so essential that long periods of sleep depravation eventually results in stress-related deaths (this has happened with lab animals, and it is possible that the same can happen with us). Missing even one single night of sleep may affect our mental performance in decision-making on the next day.