Glossary of Sleep-related terms

Sleep walking (Somnambulism)

Arising from bed during a period when there is a simultaneous occurrence of incomplete wakefulness and NREM sleep. The eyes are usually open, but appear not to be focusing. If victims do not awaken during the episode, they do not remember the event. An extremely common phenomenon, occurring in up to 40 percent of children, with a peak incidence at 12 years of age. Sleepwalking typically occurs in the first third of the night during deep NREM sleep (stages 3 and 4).1