AP PSYCHOLOGY

Detailed explanation-1: -The activity levels are like when you’re awake. That’s why REM sleep is the stage where you’ll have intense dreams. At the same time, major muscles that you normally control (such as arms and legs) can’t move. In effect, they become temporarily paralyzed.

Detailed explanation-2: -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-3: -Brain imaging studies have found, for example, that the primary visual cortex, the first part of the brain involved in consciously decoding visual signals when people are awake, shows very little activity when they are dreaming during REM sleep.

Detailed explanation-4: -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-5: -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. Muscle tone, pulse, and breathing rate decrease in N3 sleep as the body relaxes even further. The brain activity during this period has an identifiable pattern of what are known as delta waves.