A person who is sleepwalking walks or makes other movements that seem purposeful. This occurs while in a state of partial wakefulness from deep sleep. Contrary to popular belief, sleepwalkers don't act out their dreams. Sleepwalking doesn't take place during the dreaming stage of sleep.
Sleepwalking is also called somnambulism. It is common in school-age children. Repeated sleepwalking is more common in boys. It is frequently associated with nighttime bedwetting.
Sleepwalking probably occurs because the brain's ability to regulate sleep/wake cycles is still immature. Most children outgrow the symptoms as their nervous systems develop. Sleepwalking that begins later in life or lasts into adulthood may have psychological causes. These include extreme stress or, rarely, medical causes such as epilepsy.
Sleep terrors are a disorder in which a person wakes up quickly in an extremely frightened state. Sleep terrors (also called night terrors) are related to sleepwalking. The disorder usually occurs in young children.
Sleepwalking and sleep terrors tend to run in families.