PSYCHOLOGY OF EMOTIONS

Detailed explanation-1: -These four sleep stages are called non-rapid eye movement (non-REM) sleep, and its most prominent feature is the slow-wave (stage IV) sleep. It is most difficult to awaken people from slow-wave sleep; hence it is considered to be the deepest stage of sleep.

Detailed explanation-2: -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. Your brain also uses this time to cement information into memory, making it an important stage for learning.

Detailed explanation-3: -Stage 3 sleep is also known as N3 or deep sleep, and it is harder to wake someone up if they are in this phase.

Detailed explanation-4: -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-5: -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).