Yes, night terrors are different from nightmares. While they both occur during sleep, night terrors take place during the first hour or so after bedtime during the deepest form of sleep, clinically called non-rapid eye movement or non-REM sleep. Also, night terrors may be associated with physical activity during sleep.

Children in the throes of a sleep terror may scream, flail around in bed, and often attempt to get up and run away, regardless of their surroundings. Occasionally, they will hurt themselves during these episodes and may bother other family members.

In contrast, nightmares occur during REM sleep or "dream" sleep, when muscles other than those used for breathing and eye movement are paralyzed, so physical activity, such as sleep walking, and physical reaction to night terrors do not occur.

A nightmare is a long, frightening dream, accompanied by unpleasant and vivid emotions, such as fear, horror or desperation, and is common among individuals at any age. While children can wake up from a nightmare relatively easily and vividly remember the dream, or fragments of it, children experiencing a night terror do not fully wake up and do not recall the episode the next morning. Also, night terrors typically start between the ages of 4 and 10 and disappear during adolescence.

Although a child may appear to be awake during a sleep terror by looking at you and talking to you, they are not awake or aware of their surroundings. If forcibly awakened during the episode, they are likely to be confused and disoriented.

Both nightmares and night terrors cause sweating, rapid breathing, fast heart beats and dilated pupils. These physical changes are much more pronounced during a night terror.

Night terrors are primarily related to genetic and developmental factors. But it's important to know that children with occasional sleep terrors show no more emotional or psychological problems than children who do not experience this phenomenon.

Parents should not forcibly intervene during a child's night terror. Do not wake the child; it may only prolong the event. The parents' main job is to ensure their child's safety should he attempt to get up and flee. If the child wakes up, it may help to talk to him in a quiet tone about something pleasant and re-orient him to the safety of his room and home. A child who has a sleep terror will probably drift back into a peaceful sleep.

Children who experience sleep terrors should be kept on a regular sleep schedule. Being overly tired or sleep deprived can sometimes trigger an episode. For the child with frequent episodes of night terror, especially those who regularly get up and try to flee or engage other family members, a consultation with a sleep disorders specialist is in order, who can recommend appropriate therapy. Talk to your child's pediatrician.