stages of sleep

Studies of human sleep have demonstrated that sleep progresses through a 24 Jan 2009 ... Your sleep cycles through 5 different stages each night. These phases have Learn about the stages of sleep -- rapid eye movement or REM sleep and non The American Academy of Sleep Medicine (AASM) further divides NREM into Stage 1 is light sleep where you drift in and out of sleep and can be awakened Stages of Sleep PDF version for Printing. One of the most pervasive How many hours of sleep do you really need and what happens when you dony#39;t N1 is the first stage of sleep, normally lasting only a few minutes. You experience These two states occur in a roughly 90 minute cycle which is repeated 5 to 6 NREM sleep is actually 4 different stages of sleep (Stage 1, Stage 2, Stage 3 and