Sleep quality changes with transition from one sleep stage into another. Sleep stages are monitored and examined clinically with polysomnography, which provides data regarding electrical and muscular states during sleep. Waking The waking stage is referred to as relaxed wakefulness, because this is the stage in which the body prepares for sleep. All people fall asleep with tense muscles, their eyes moving erratically. Then, normally, as a person becomes sleepier, the body begins to slow down.
Muscles begin to relax, and eye movement slows to a roll.
Back to Top Stage 1 Stage 1 sleep, or drowsiness, is often described as first in the sequence, especially in models where waking is not included. The eyes are closed during Stage 1 sleep, but if aroused from it, a person may feel as if he or she has not slept. Stage 1 may last for five to 10 minutes. Stage 2 Stage 2 is a period of light sleep during which polysomnographic readings show intermittent peaks and valleys, or positive and negative waves. These waves indicate spontaneous periods of muscle tone mixed with periods of muscle relaxation.