Sleepwalking, formally known as somnambulism, is a behavior disorder that originates during deep sleep and results in walking or performing other complex behaviors while asleep. It is much more common in children than adults and is more likely to occur if a person is sleep deprived. Because a sleepwalker typically remains in deep sleep throughout the episode, he or she may be difficult to awaken and will probably not remember the sleepwalking incident.
Sleepwalking usually involves more than just walking during sleep; it is a series of complex behaviors that are carried out while sleeping, the most obvious of which is walking. Symptoms of sleepwalking disorder range from simply sitting up in bed and looking around, to walking around the room or house, to leaving the house and even driving long distances. It is a common misconception that a sleepwalker should not be awakened. In fact, it can be quite dangerous not to wake a sleepwalker.
The prevalence of sleepwalking in the general population is estimated to be between 1% and 15%. The onset or persistence of sleepwalking in adulthood is common, and is usually not associated with any significant underlying psychiatric or psychological problems. Common triggers for sleepwalking include sleep deprivation, sedative agents (including alcohol), febrile illnesses, and certain medications.
The prevalence of sleepwalking is much higher for children, especially those between the ages of three and seven, and occurs more often in children with sleep apnea. There is also a higher instance of sleepwalking among children who experience bedwetting. Sleep terrors are a related disorder and both tend to run in families.
Sleepwalking is most often initiated during deep sleep but may occur in the lighter sleep stages or NREM, usually within a few hours of falling asleep, and the sleepwalker may be partially aroused during the episode.
In addition to walking during deep sleep, other symptoms of sleepwalking include:
- Sleep talking
- Little or no memory of the event
- Difficulty arousing the sleepwalker during an episode
- Inappropriate behavior such as urinating in closets (more common in children)
- Screaming (when sleepwalking occurs in conjunction with sleep terrors)
- Violent attacks on the person trying to awaken the sleepwalker
According to the National Sleep Foundation’s 2004 Sleep in America Poll, 1% of pre-school children and 2% of school-aged children walk in their sleep at least a few nights per week.