Sleep Occurs in Four Stages

During the sleep, homeostasis will fluctuate because sleep occurs on four stages (Davidmann 1998). The individual goes from awake to Stage 1, then to 2, 3 and finally 4. After spending about twenty minutes in Stage 4, individuals return to Stage 1 and progress back to Stage 4. The individual will continue to make these cycles throughout their sleep. Most individuals will experience about 4 to 5 cycles a night (Davidmann, 1998). During Stage 1 the individual will experience what has been named REM (Rapid Eye Movement). During REM the body will show more signs of consciousness by spontaneous muscle contractions, flagellate excretion, and oculomotor coordination (eye movement). The body will experience these tensions and reactions because this is the active time of sleep in the average human (Davidmann, 1998). REM is the time in which the individual will have their dreams. Nathaniel Kleitman discovered it in 1953. It always occurs in the lightest stage of sleep, Stage 1. It has been given its name because of the muscle contractions in the eye motor receptors. These electrical impulses originate from the brain stem and then travel to the eyes to produce imagery. The catalysts for these impulses are triggered by the subconscious mind and the emotions within it (Davidmann, 1998). The REM will usually begin ninety minutes after sleep is initiated and will last roughly ten to fifteen minutes. The REM will end and the individual will slip into deeper periods of sleep until the fourth stage is reached. Once this occurs the mind begins to come out of the deeper sleep stages until it reaches REM once again. The interesting factor is that each time the sleeper enters the REM phase of sleep the REM phase will increase in length. This repeats four to five times in the average sleep. The reason the dreams occur in the REM or the lightest stage is that this is the only state in which the conscious mind can interpret the imagery of the subconscious.