AP PSYCHOLOGY

Detailed explanation-1: -During stage 1, which is light sleep, we drift in and out of sleep and can be awakened easily. Our eyes move very slowly and muscle activity slows. People awakened from stage 1 sleep often remember fragmented visual images.

Detailed explanation-2: -Stage 1 Non-REM (Rapid Eye Movement) Sleep Stage 1 kicks off the sleep cycle, as we transition from wakefulness to a light sleep. This first stage is when you’re just drifting off to slumber. Your heartbeat, eye movements, and breathing slow down; your muscles relax; and your brain activity begins to taper off.

Detailed explanation-3: -Stage 1. Stage 1, also called N1, is essentially when a person first falls asleep. This stage normally lasts just one to seven minutes. During N1 sleep, the body has not fully relaxed, though the body and brain activities start to slow with periods of brief movements.

Detailed explanation-4: -The human body cycles through two phases of sleep, (1) rapid eye movement (REM) and (2) non-rapid eye movement (NREM) sleep, which is further divided into three stages, N1-N3. Each phase and stage of sleep includes variations in muscle tone, brain wave patterns, and eye movements.

Detailed explanation-5: -Stages 3 and 4, Slow-Wave Sleep 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. Each has distinguishing characteristics. Stage 3 lasts only a few minutes and constitutes about 3 to 8 percent of sleep.