As the sleep cycle evolves through the night, people tend to:

• spend more time in REM sleep and less time in NREM sleep.
• spend more time in NREM sleep and less time in REM sleep.
• spend a more or less equal amount of time in REM sleep and NREM sleep.
• spend more time in stage 4 sleep and less time in REM sleep.

By the end of the night you spend half of your sleep time in this stage.

• NREM 1
• NREM 2
• NREM 3
• REM

If you were awakened during this sleep stage you might insist you were not asleep.

• NREM 1
• NREM 2
• NREM 3
• REM

You sleep most deeply during this stage, which is characterized by delta waves or slow waves.

• NREM 1
• NREM 2
• NREM 3
• REM

What happens just before you enter REM sleep? You:

• cycle back up through NREM 2 & NREM 1
• stay in NREM 3 for another 30 minutes
• go directly from NREM 3 to REM
• wake up, but you won't remember it the next day

During REM, your brainwave patterns are similar to:

• NREM 1
• NREM 2
• NREM 3
• When you're awake

Why is REM sleep considered paradoxical?

• Internally aroused
• Externally paralyzed
• Brainstem blocking messages from motor cortex
• all of these

Slow wave sleep consists of stages ______ of sleep and is dominated by _____ waves. 

• 1 and 2; beta
• 2 and 3, alpha
• 3 and 4; delta
• 1 and 2; delta

Sleep spindles are seen during

• NREM1
• NREM2
• NREM3
• REM

In most people, muscle paralysis occurs during

• REM
• NREM1
• NREM2
• NREM3