http://www.sleepfoundation.org/site/apps/nl/content.asp?c=huIXKjM0IxF&b=2457455&ct=3501387
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.