PSYCHOLOGY OF EMOTIONS

Detailed explanation-1: -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-2: -There are 4 stages of sleep that your body experiences each night (usually spanning 3-5 sleep cycles): Light sleep, deep sleep (also referred to as slow wave sleep or SWS), REM sleep and awake. For a more in-depth explanation of how this works, check out Understanding Sleep Cycles and the Stages of Sleep.

Detailed explanation-3: -It takes, on average, about 90 minutes to go through each cycle. Completing five cycles a night means you’d get 7.5 hours of sleep, while six full cycles translates to about 9 hours of sleep.

Detailed explanation-4: -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.