For a long time, sleepwalkers have been known to walk while asleep and even commit murders. There are countless stories of sleepwalkers suddenly     1    up and finding themselves naked in their backyards.     2    1% and 15% of the population are likely to sleepwalk, which     3    people getting up and walking around while     4    and often doing strange things. Frequent sleepwalking can     5    health problems since it interrupts normal patterns of sleep.
    Sleepwalking     6    in the deep stage of sleep when slow brain waves begin to appear. It is one of a group of disorders     7    as     8    behaviors or activities that happen during sleep. These range from teeth     9    to eating while asleep.
    Sleepwalking has long been considered a disorder linked to parts of the brain     10    control arousal, however, the specific pathways and processes involved are still     11    .
    Our bodies function according to a 24 hour     12    , where brain wave activity and hormones fluctuate partly under the influence of     13    factors such as light, but also due to internal regulation. Some researchers believe that slight differences in this cycle could be linked to sleepwalking.
    Sue Wilson     14    a sleep clinic and is investigating the causes of sleepwalking. "We think that     14    sleepwalkers are more stressed after a night's sleep than     16    sleepers," she says. "A sleepwalker's stress levels can get even     17    when they become concerned about their sleepwalking. It's an annoying     18    ," says Wilson, "they worry about sleepwalking so they can't     19    and of course, if your sleep prevents yourself from going into a deeper sleep and so you're more     20    to sleepwalk."