Night terrors are not nightmares. In fact they are not even dreams. Also known as sleep terrors, night terrors occur during non-REM sleep, not during REM sleep when the majority of us dream. They typically occur within the first few hours of going to sleep. The person may wake up for about twenty seconds and in most cases settle back to sleep. There is typically an increase in heart rate, blood pressure and respiration. There will also be a classic physiological response to fear, with dilated pupils, confusion or panic and sweat. Subjects may scream or yell during an episode and flail their arms and legs around or sit upright in bed. In adults, alcohol, stress, fever or lack of sleep may trigger night terrors and they are believed to have their basis in a purely biological function.
If the terror wakes the sleeper up, they may recall a single image of terror but if they fall back to sleep there is unlikely to be any recall of the feeling.
If you or someone you know experiences more than three or four episodes of night terror a month, then you or they might be suffering from an anxiety disorder. It is important to consult a doctor if this is the case. Night terrors tend to be most common in children between the ages of three and eight, and most sleep experts urge parents and carers not to rush to their child to try and wake and comfort them as this can intensify or aggravate the night terror. You should instead let the night terror run its course and the child will rarely recall the event in the morning. There is not much evidence that night terrors reflect deep psychological problems and occasional night terrors are considered quite normal in young children. See also Sleep paralysis, and Incubus and succubus entries in SPIRITS AND GHOSTS.... The Element Encyclopedia