Psych Unit 3 Sleep (REM & NREM, Stages of Sleep)

States or Types of Sleep

NREM sleep and REM sleep.

NREM Sleep

� Approx. 80% of the time is spent asleep is in NREM sleep.
� The first half of the night has more NREM sleep than the second half.

Stage 1 of NREM Sleep

� Decreased heart rate, respiration, body temperature and muscle tension.
� Stage 1 is when the sleeper may experience a hypnic jerk. Hypnic jerks are quite common in stage 1.
� Approximately 5-10 minutes.
� EEG pattern shows a decrease in ALPHA WAVE prod

Stage 2 of NREM Sleep

� Light stage of sleep.
� Stage 2 lasts about 10-20 minutes.
�Body movement lessens, breathing becomes regular, heart rate, blood pressure and temperature continues to fall.
� In Stage 2 EEG shows SLEEP SPINDLES (brief bursts of high frequency periodicall

Stage 3 of NREM Sleep

� Stage 3 is a moderate deep sleep stage and lasts for approximately 10 minutes.
� Heart rate, blood pressure and body temperature still continue to drop and breathing becomes slow and steady.
� An individual is external relaxed and becomes less and less

Stage 4 of NREM Sleep

� Deepest stage of sleep. When muscles are completely relaxed and movement is minimal.
� DELTA WAVES dominate the EEG pattern and are even slower and larger than in STAGE 3.
� When the EEG shows that DELTA WAVES comprise more than 50%, the person has ente

REM Sleep

� A period of REM sleep of rapid eye movement sleep during which the eyeballs rapidly move beneath the closed eyelids, darting back and forth and up and down in jerky movements.
� The EEG shows irregular brain wave patterns with short, high frequency beta