MashGet

Sleepwalking from WikiPedia:

Sleepwalking (also called somnambulism or noctambulism) is a parasomnia or sleep disorder where the sufferer engages in activities that are normally associated with wakefulness while he or she is asleep or in a sleep-like state. Sleepwalking is usually defined by or involves the person affected apparently shifting from his or her prior sleeping position and moving around and performing normal actions as if awake (cleaning, walking and other activities).

Somnambulists are not exactly unconscious during their nocturnal sleepwalking episodes, but are not conscious of their actions on a level where memory of the sleepwalking episode can be recalled. Because of this, unless the sleepwalker is awakened by someone else, the sleep disorder can go unnoticed. Sleepwalking is more commonly experienced in people with high levels of stress, anxiety or psychological factors, and in people with genetic factors (family history), or sometimes a combination of both.

Read more on WikiPedia