Physiology of Sleep and Clinical Characteristics

Sleep is defined as a natural decrease in the perception of the external environment that occurs periodically and reversibly, but retaining a certain degree of reactivity towards the environment and autonomous functions. The dream is considered an active process of biological, cyclical and, is essential for survival. Most adults require an amount of sleep between 7 8 hours per day; however, there are individual variations regarding the schedule, duration, and internal structure of the dream. In this regard, recent research has identified a possible genetic basis to explain these differences.