The exact cause of night terrors in children is not really known but associations have always been drawn between events such as disrupted sleep patterns or childhood anxiety. Now, researchers from the University of Montreal, have established that slightly less than half of night terrors could be due to heredity.
When a child experiences night terrors they appear unsettled and may moan in their sleep. There may come a point where they thrash, kick out and possibly scream. In the morning the child is unable to remember the incident. According to sleep experts night terrors differ from nightmares. If a child experiences a nightmare they will frequently wake up and be able to respond to words of comfort and be able to recall what they experienced.
The research team involved 390 pairs of identical and fraternal twins in their study. Twins were assessed for night terrors at 18 months and again at 30 months. In their findings, if one of the identical twins experienced night terrors, there was a 68 percent chance of the other twin having night terrors. In fraternal twins, the likelihood of the second twin experiencing night terrors reduced to 24 percent.
In comments to The Canadian Press, Professor Jacques Montplaisir, a neuroscientist and psychiatrist at the University of Montreal said, "the study brings strong evidence that genetics play a major role." He went on to say that links also exist between night terrors and sleep walking.
According to Montplaisir, environmental factors do have a role in night terrors. Research points to separation anxiety and tensions within the family as two factors felt to have an association.
In describing night terrors, professor Montplaisir says that affected children experience a rapid state of arousal that results in an increase in heart rate, flushing and sweating.
"if you try to wake up a child during a night terror episode, the child is confused, he has no memory of any dreams, although on some occasions he may have just the impression of . . .a painful sensation without being able to give any description. Any attempt to wake the child may increase their agitation and prolong the episode."
There is no treatment for night terrors and most children seem to grow out of the condition within a few weeks or months.
The study is published in the December issue of Pediatrics.