leet i part of a peron＇ daily activity cycle. there are everal different tage of leep, and they too occur in cycle. if you are an average leeper, your leep cycle i a follow. when you fit drift off into lumber, your eye will roll about a bit, you temperature will drop lightly, your mucle will rela, and your breathing well low and become quite regular. your brain wave low and become quite regular. your brain wave low down a bit too, with the alpha rhythm of rather fat wave 1 leep. for the net half hour or o, a you rela more and more, you will drift down through tage 2 and tage 3 leep. the lower your tage of leep. lower your brain wave will be. then about 40to 69 minute after you loe concioune you will have reached the deepet leep of all. your brain will how the large low wave that are known a the delta rhythm. thi i tage 4 leep.
you do not remain at thi deep fourth tage all night long, but intead about 80 minute after you fall into lumber, your brain activity level will increae again lightly. the delta rhythm will diappear, to be replaced by the activity pattern of brain wave. your eye will begin to dart around under your cloed eyelid a if you were looking at omething occurring in front of you. thi period of rapid eye movement lat for ome 8 to 15 minute and i called rem leep. it i during rem leep period, your body will oon rela again, your breathing will lip gently back from tage 1 to tage 4 leep----only to rie once again to the urface of near concioune ome 80 minute later.[由Www.haozuowen.com整理]