Q. What can you tell me about sleepwalking? Why does it occur? The 10-year-old daughter of my best friend has started to sleepwalk and it’s scary!

A. Sleepwalking is type of parasomnia (abnormal sleeping pattern). It is more common in children than in adults. There are several different types of NREM parasomnias or sleepwalking. The most common type of sleepwalking tends to occur during the first third of the night in non-REM sleep. This type of sleep is a lighter sleep, and it usually does not involve dreams. The part of the brain that generates complex behaviors is believed to remain awake during "sleep." The sleepwalker will tend to repeat daily activities but likely will not initiate some routine activity that he or she has not done before. During sleeping walking the decision-making part of the brain likely is not awake. There are even some sleepwalkers who try to eat, a condition referred to as nocturnal sleep-related eating disorder (NSRED). This can be dangerous if they cut themselves while trying to fix a snack or burn themselves on the hot stove.

Reportedly, children in the age group of 3-12 have the highest prevalence of sleepwalking. Estimates are that nearly 17 percent of these children walk in their sleep. Typically, sleepwalking in children tends to fall off after puberty.

Interestingly, sleepwalkers often have their eyes wide open during an episode and may even engage in conversation with others. If the individual does not recall the conversation or even the episode of sleepwalking, he or she was likely sleepwalking. Unfortunately, sleepwalking can lead to fatigue and sleepiness the next day and can contribute to sleep deprivation.

Sleepwalking tends to run in families. Children whose parent(s) sleepwalked in childhood are more likely to do so. A study published in the British Journal of Psychology concluded that a first-degree relative of a sleepwalker is ten times more likely to sleepwalk than the rest of the population. A separate study published in the journal Neurology concluded that twins are more likely to sleepwalk. Reportedly, a twin is five times more likely to experience episodes of sleepwalking if the other twin sleepwalks. One study has linked sleepwalking with a mutated gene (located somewhere on chromosome 20) that can be passed from parent to child. Researchers from Washington University School of Medicine reported that those with the mutated gene reportedly have a 50% chance of passing it to the next generation.

Does this mean that sleepwalking in offspring is inevitable? Apparently not. It is likely that heritable factors predispose an individual to develop sleepwalking (and/or night terrors), but the actual exhibition of the trait may be influenced by environmental factors.

Consensus is that there is a reason for sleepwalking to occur. Behaviors do not erupt from a vacuum. Some potential contributors include:

  • Unhealthy sleep routines. Sometimes a bad dream or night terror may trigger it, or a scary movie news reports in living color of natural disasters, or even reading a scary story.
  • Something that changed in the child’s life. Did something change in this child’s life?
    • Has she been given a new chore and is anxious about doing it correctly?
    • Has the family recently moved to a new house or relocated to a different city?
    • Has the child changed schools or moved to another grade with a different teacher?
    • Has the child started taking music lessons and is anxious about performance?
    • Have the parents divorced or did a parent or other close family member become very ill or die?
    • Is the child being subjected to bullying behaviors at school?

If you can figure it out and resolve it, or at least discuss it reassuringly with the child if it cannot be resolve, this may help to relieve some of the anxiety. Sometimes preschoolers sleepwalk as the function of imagination begins to develop. In general, sleepwalking among children tends to peak during preschool years and often resolves after puberty.

At least some sleepwalking may be preventable by developing and maintaining a regular and consistent sleep schedule; going to bed at the same time every night and waking up at the same time each morning. Avoiding mid-day naps may help, as well. Shut off all electronics an hour before bedtime—and minimize exposure to terror-inducing information. Do something restful such as reading a favorite book. Some advocate having a relaxing bedtime routine that ends in the room where the child sleeps.