Sleep epilepsy is a type of epilepsy in which nocturnal seizures may occur while falling asleep, during sleep or during awakening from sleep. The movements of a seizure may indeed be confused with night terrors and may both involve repetitive, large movements of the trunk and limbs. However, the form of movement is highly constant and more frequent in seizures, and slower in night terrors compared to seizures.
In addition, sleep seizures are shorter in duration, 10 to 30 seconds, whereas night terrors tend to last several minutes. The EEG shows epileptiform discharges during seizures and can be used to differentiate seizures from night terrors based on the patient’s response to antiepileptic drugs, video EEG monitoring and polysomnography.