Ever since I was a child, I had always had problems with sleep walking, talking, mumbling, etc. Only now has the question come into my head- what is happening in our brains during this crazy phenomenon?
According to the National Sleep Foundation, 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.
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.
There is an interesting article on google scholar that explains that sleepwalking is a dissociation between body sleep and mind sleep. Sleepwalking refers to various complex motor behaviors, including walking, that are initiated during deep (stages 3–4) non-rapid-eye-movement (NREM) sleep (slow-wave sleep). Some episodes may be limited to sitting up, fumbling, picking at bedclothes, and mumbling. Patients usually stand up and walk around quietly and aimlessly. Occasionally, sleepwalkers become agitated, with thrashing about, screaming, running, and aggressive behavior. Sleepwalking is regarded as a disorder of arousal with frequent but incomplete awakening from slow-wave sleep. The association of abrupt motor activity with diffuse, rhythmic, high-voltage bursts of delta electroencephalographic (EEG) activity indicates a dissociation between mental and motor arousal.
MedicalDaily.com also published an article explaining that sleepwalking happens at the tail end of the NREM phases, when your body has fallen into a semi-conscious state. Formally, the brain’s delta waves are their most active. Delta waves are the slowest waves yet have the greatest amplitude, which contributes to the depth of sleep yet retained ability to be physically active.
Why certain people’s brains make the transition from high delta wave frequency to sleepwalking, and not simply continued sleep, is something of a mystery. But scientists speculate the behavior likely has roots in poor maturation during childhood. Neurologist Antonio Oliviero, of the National Hospital for Paraplegics in Toledo, Spain, believes from his research that faulty wiring related to the neurotransmitter GABA (gamma-aminobutyric acid) could be the underlying mechanism.
“In children the neurons that release this neurotransmitter are still developing and have not yet fully established a network of connections to keep motor activity under control,” Oliviero explained in Scientific American. Because GABA suppresses the brain’s motor control signals, a shortage of the substance could lead to a sleepy child whose dreams get turned into reality. “In some, this inhibitory system may remain underdeveloped — or be rendered less effective by environmental factors — and sleepwalking can persist into adulthood.”
It also runs in the family (no pun intended). If one parent is a sleepwalker, the child has a 45% chance of becoming one. If both parents are, the chances jump to 60 percent. Depressed people are three times more likely to sleepwalk, not to mention migraine sufferers and people with Tourettes syndrome who are four to six times more likely to sleepwalk.
Considering my father was (and still is) an extreme sleepwalker, this is all starting to make sense to me now. It still blows my mind that I am one of the only 3.6 percent of U.S. adults who have walked in their sleep at least once in the previous year… lets just hope that I don’t pass on this crazy habit genetically to my future children!