AP PSYCHOLOGY

Detailed explanation-1: -Parasomnias – These are unusual experiences or behaviors that occur during sleep; they include sleep terror disorder and sleepwalking (which occur during stage 4 sleep) and nightmare disorder (which occurs during rapid eye movement [REM] sleep).

Detailed explanation-2: -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.

Detailed explanation-3: -Sleep occurs in five stages: wake, N1, N2, N3, and REM. Stages N1 to N3 are considered non-rapid eye movement (NREM) sleep, with each stage a progressively deeper sleep.

Detailed explanation-4: -Stage 4 of non-REM sleep Stage 4 is an even deeper sleep where the brain waves further slow and sleepers are very difficult to wake. It’s believed that tissue repair occurs during the stage of sleep and that hormones are also released to help with growth.