When you first drift off into slumber, your eyes will roll about a bit, your temperature will drop slightly, your muscles will relax, and your breathing will become quite regular. Your brain waves slow down a bit, with the alpha rhythm predominating for the first few minutes. This is the first stage of sleep. For the next 30 minutes or so, you will drift down through Stage 2 and Stage 3. The lower your stage of sleep, the slower your brain waves will be. About 40-60 minutes after you lose consciousness, you will reach the last stage. Your brain waves will show the delta rhythm. You may think that you stay at this deep stage all the rest of the night, but that turns out not to be the case. About 80 minutes after you fall into slumber, your activity cycle will increase slightly. The delta rhythm will disappear, to be replaced by the activity pattern of brain waves. Your eyes will begin to dart around under your closed eyelids. This period of Rapid Eye Movements lasts for 8-15 minutes and is called REM sleep.

During both light and deep sleep, the muscles in your body are relaxed but capable of movement. As you slip into REM sleep, a very odd thing occurs — most of the voluntary muscles in your body become paralyzed. Although your brain shows very rapid bursts of neural activity during REM sleep, your body is incapable of moving. REM sleep is accompanied by extensive muscular inhibition.

91. On the part of an average sleeper, _____ of sleep in cycles.

A. there is one stage

B. there are two stages

C. there are six stages

D. there are four stages

92. When a person falls into the state of sleep, _____.

A. his eyeballs will roll about a bit

B. his mind will relax more and more

C. his breathing will slow for minutes

D. his temperature will increase slightly

93. The lower your stage of sleep, _____.

A. the faster your eyes will roll about

B. the quieter your breath will become

C. the slower your brain waves will be

D. the higher your temperature will be

94. After you have reached the deepest sleep, _____.

A. you will stay at the fourth stage the rest of the night

B. you will lose your consciousness for 40－60 minutes

C. your brain waves will show the delta rhythm

D. your brain waves will show the alpha rhythm

95. In the REM sleep, _____.

A. the delta rhythm will disappear

B. the activity pattern will appear

C. something will occur in front of you

D. your eyes will begin to dart around

96. You will fall into the fourth stage of sleep _____.

A. about 80 minutes after you fall into slumber

B. some 10 minutes after your fall into REM sleep

C. about 40 minutes after you lose consciousness

D. some 30 minutes after your brain waves slow

97. The first paragraph of this passage tells us about _____.

A. the rhythms of brain waves

B. the daily activities of sleep

C. the stages of sleep in cycles

D. the daily activities in cycles

98. In this passage, the word “paralyzed” means _____.

A. unable to move

B. unable to think

C. unable to work

D. unable to speak

99. The phrase “extensive muscular inhibition” means _____.

A. the body is incapable of movement

B. the muscles in the body are relaxed

C. voluntary muscles are capable of movement

D. the brain shows rapid burst of neural activity

100. The best title for this passage would be _____.

A. Brain Waves

B. Sleep Cycles

C. Daily Activities

D. Body Activities