Washington, Apr 3 : People predisposed to sleepwalking should keep a regular bedtime to avoid unwanted evening strolls, according to researchers at the Universite de Montreal.
This sleep disorder, also called somnambulism, makes the sufferers engage in activities like cleaning, walking, normally linked to wakefulness while he or she is asleep or in a sleeplike state. It affects up to four percent of adults, and can cause mental confusion or bouts of amnesia in those affected as they wander unresponsive to their environment.
The study, led by Antonio Zadra, evaluated 40 suspected sleepwalkers. All the participants were referred to the Sleep Research Centre at Sacre-Coeur Hospital, a Universite de Montreal teaching hospital, between August 2003 and March 2007.
"Our study found that sleep deprivation can precipitate sleepwalking in predisposed individuals. Sleepwalkers are best to maintain a regular bedtime and avoid sleep deprivation if they wish to steer clear of somnambulism," said Zadra.
All the subjects taking part in the study, agreed to have their baseline sleep patterns monitored during an initial all-night assessment. In a subsequent visit, the researchers kept the patients awake for whole evening and constantly supervised them.
After the patients were awake for 25 hours, they were allowed to have a recovery sleep the next morning. During each sleep period, the subjects were videotaped enabling the researchers to evaluate their behaviour, which ranged from playing with bed sheets to trying to jump over the bed rails. Subjects were evaluated on a three-point scale based on the complexity of their actions.
The researchers came up with remarkable results, as during baseline sleep, only half of patients exhibited some 32 behavioural episodes. During recovery sleep, 90 percent of patients demonstrated a total of 92 behavioural episodes.
Also, the study found that sleepwalkers, previously thought to suffer from an inability to sustain slow-wave or deep sleep, had increased difficulty in passing from slow-wave sleep to another sleep stage or to be fully awake following sleep deprivation.
"This research also reveals that objective methods can now be used for investigating and diagnosing sleepwalking," said Dr. Zadra.
The study is published in the recent issue of the Annals of Neurology, the official journal of the American Neurological Association.