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Section C
Sleep is part of a person's daily __36__ cycle. There are several different stages of sleep and they occur in cycles, If you are an __37___ sleeper, your sleep cycle is as follows. When you first drift off into slumber, your eyes will roll about a bit, your _____38_____ will drop slightly, your ___39__ will relax, and your ___40____ will slow and become quite ____41____ Your brain waves slow down a bit too with the alpha rhythm of rather fast waves ____42____ for the first few minutes. This is called stage 1 sleep. For the next half hour or so as you relax more and more you will drift down through stage 2 and stage 3 sleep. The lower your stage of sleep the slower your brain waves will be. Then about 40 to 60 minutes after you lose _____43____ you will have reached the deepest sleep of all.
________________________________________44__________________________________. This is stage 4 sleep.
You do not remain at this deep fourth stage all night long, but instead about 80 minutes after you fall into slumber, your brain activity level will increase again slightly. The delta rhythm will disappear to be replaced by the activity pattern of brain waves. _______________________________45______________________________.
This period of rapid eye movement lasts for some ~ to 15 minutes and is called REM sleep. It is during REM sleep that most dreams seem to occur. ______________________46________________ .You will slip gently back from stage I to 4.
