AP PSYCHOLOGY

Detailed explanation-1: -Sleep occurs in five stages: wake, N1, N2, N3, and REM.

Detailed explanation-2: -In the deepest level of sleep, stage IV sleep, the predominant EEG activity consists of low frequency (1–4 Hz), high-amplitude fluctuations called delta waves, the characteristic slow waves for which this phase of sleep is named. The entire sequence from drowsiness to deep stage IV sleep usually takes about an hour.

Detailed explanation-3: -Stage five is the final stage of sleep where we begin to dream, and it occurs about 90 minutes into the sleep cycle. The eyes move rapidly, breathing becomes shallow and rapid, and blood pressure and heart rate increase. During REM sleep, the arms and legs are paralyzed so that sleepers can’t act out their dreams.

Detailed explanation-4: -Stages 3 and 4, Slow-Wave Sleep Sleep stages 3 and 4 are collectively referred to as slow-wave sleep (SWS), most of which occurs during the first third of the night. Each has distinguishing characteristics. Stage 3 lasts only a few minutes and constitutes about 3 to 8 percent of sleep.

Detailed explanation-5: -Stage 4: REM Sleep While your brain is aroused with mental activities during REM sleep, the fourth stage of sleep, your voluntary muscles become immobilized. During REM sleep, your brain’s activity most closely resembles its activity during waking hours.