A sleep disorder involving abrupt awakening from sleep with behaviour consistent with terror. The cause is unknown but night terrors are commonly associated with periods of emotional tension, stress or conflict.
Night terror (sleep terror) occurs during deep sleep. Night terror is similar to nightmares except that nightmares usually occur during lighter REM sleep and include unpleasant or frightening dreams.
Night terror occurs most often in pre-adolescent boys, although it can occur in girls and in adults. It is fairly common in children 3 to 5 years old, and incidence usually reduces greatly after that. It may run in families. Night terror can occur in adults, especially with emotional tension and/or the use of alcohol.