A night terror is a brief episode of extreme panic and terror followed by retrograde amnesia (memory loss of events that previously occurred) the following morning. Night terrors are characterized by high mobility and intense vocalizations in the dreamer. The dreamer, typically a child, might suddenly sit up and scream or shout in distress during a night terror. When a night terror occurs, the dreamer is unaware of the dream and experiences retrograde amnesia and, therefore, seldom experiences distress in waking hours. In general, night terrors occur less often than nightmares but more often than sleepwalking. This entry first further describes and defines night terrors, then presents information on prevalence and etiology, and concludes with discussions of differential diagnosis and treatment.