Contemporary culture increasingly suffers from problems of attention, over-stimulation, and stress, and a variety of personal and social discontents generated by deceptive body images. This book argues that improved body consciousness can relieve these problems and enhance one's knowledge, performance, and pleasure.
In the R&K standard, NREM sleep was divided into four stages, with slow-wave sleep comprising stages 3 and 4. In stage 3, delta waves made up less than 50% of the total wave patterns, while they made up more than 50% in stage 4. Furthermore, REM sleep was sometimes referred to as stage 5. In 2004, the AASM commissioned the AASM Visual Scoring Task Force to review the R&K scoring system.
Cycles. Sleep does not progress through all of these stages in sequence, however. Sleep begins in Stage One and progresses into stages 2, 3, and 4. Then, after Stage Four sleep, Stages Three, then Two are repeated before going into REM sleep. Once REM is over, we usually return to Stage Two sleep. Sleep cycles through these stages approximately 4 or 5 times throughout the night. We typically enter REM approximately 90 minutes after falling asleep. The first cycle of REM often lasts only a short amount of time, but each cycle becomes longer. This is why we need long periods of sleep each night. If we get short periods of sleep, we canât really get through the stages we need to heal and stay healthy. REM can last up to an hour as our sleep progresses. In case you are wondering, if you feel like a dream is taking a long period of time, it really is. Contrary to what was once believed, dreams take as long as they actually seem.