Alertness

Muscle tone

Activity of brain

Summary

Wakefulness

Present

Increased

Active

Mind and body are active, you are alert

NREM

Absent

Reduced

Reduced

Mind and body are relaxed, you are asleep

REM

Absent

Absent

Active

Mind is active, but body is paralyzed, you are asleep

Sometimes, features of one state will transition into another, resulting in behaviors such as walking, talking, panic and eating during sleep. These conditions are collectively known as Parasomnias.