Experts believe that sleepwalking and sleep terrors probably occur because the brain's ability to regulate sleep/wake cycles is still immature. Most children out grow the symptoms as their nervous systems develop.
Sleepwalking that begins later in life, or lasts into adulthood, may have psychological causes, such as extreme stress, or rarely, medical causes such as epilepsy.
Contrary to popular belief, sleepwalkers don't act out their dreams. Sleepwalking and doesn't take place during the dreaming stage of sleep. The key symptom of sleepwalking is purposeful movements done while in a state of partial awakening from deep sleep.
Some sleepwalkers simply sit up in bed and move their legs. Others carry out more complex tasks such as dressing and undressing, eating or urinating.
Sleepwalking and sleep terror episodes usually occur one to two hours after going to sleep, and last from one to thirty minutes. A sleepwalker has open eyes and a blank expression, and is usually difficult, if not impossible, to awaken. The next morning, he or she won't remember the episode.
A person's history usually provides enough information for a doctor to diagnose sleepwalking, especially in children. More difficult cases may require a consultation with a sleep specialist and an overnight sleep test called polysomnography. During this test, various body functions are recorded while the person is sleeping.
In rare cases, a brainwave recording (electroencephalogram, or EEG) may be ordered to rule out seizures. Usually treatment is not necessary.
Sleepwalking usually goes away on it's own and the primary concern for a parent or caretaker is just keeping the person safe.
Other related pages at Relax and Sleep