Definition A sleep disorder involving abrupt awakening from sleep with behavior consistent with terror. The normal sleep cycle involves distinct stages from light drowsiness to deep sleep. During a night, there will be several cycles of non-REM and REM sleep. The cause is unknown but night terrors are commonly associated with periods of emotional tension , stress , or conflict. Night terror is similar to nightmares except that nightmares usually occur during REM sleep and include unpleasant or frightening dreams.
Nightmares are most common in the early morning.
If recurrent, nightmares and night terror may be associated with psychological disturbances or severe stress, especially in adults. Night terror occurs most often in preadolescent 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. They may last 10 to 20 minutes, then normal sleep returns.