AP PSYCHOLOGY

Detailed explanation-1: -Approximately 75% of sleep is spent in the NREM stages, with the majority spent in the N2 stage.[14] A typical night’s sleep consists of 4 to 5 sleep cycles, with the progression of sleep stages in the following order: N1, N2, N3, N2, REM.[15] A complete sleep cycle takes roughly 90 to 110 minutes.

Detailed explanation-2: -Stage 4: REM sleep In REM sleep, your brain waves and eye movements increase. Your heart rate and breathing also speed up. Dreaming often happens during REM sleep. Your brain also processes information during this stage, making it important for learning and memory.

Detailed explanation-3: -Stage 5: REM sleep The final stage of sleep is REM and this is the cycle where we dream. The eyes move rapidly behind the lids and breathing becomes shallow and rapid. Blood pressure and heart rate also increase during REM sleep and the arms and legs are paralyzed so that sleepers can’t act out their dreams.

Detailed explanation-4: -There are four sleep stages, including one for rapid eye movement (REM) sleep and three that form non-REM (NREM) sleep. These stages are determined based on an analysis of brain activity during sleep, which shows distinct patterns that characterize each stage.

Detailed explanation-5: -The four stages of sleep fall into two categories. The first three stages are considered non-rapid eye movement sleep (NREM), while the fourth and final stage is rapid eye movement (REM).