Sleepwalking, also known as somnambulism or noctambulism, is a phenomenon of combined sleep and wakefulness.[1] It is classified as a sleep disorder belonging to the parasomnia family.[2] Sleepwalking occurs during slow wave sleep stage in a state of low consciousness and perform activities that are usually performed during a state of full consciousness. These activities can be as benign as sitting up in bed, walking to a bathroom, and cleaning, or as hazardous as cooking, driving,[3] violent gestures, grabbing at hallucinated objects,[4] or even homicide.[5][6][7] Although sleepwalking cases generally consist of simple, repeated behaviours, there are occasionally reports of people performing complex behaviours while asleep, although their legitimacy is often disputed.[8] Sleepwalkers often have little or no memory of the incident, as their consciousness has altered into a state in which it is harder to recall memories. Although their eyes are open, their expression is dim and glazed over.[9] Sleepwalking may last as little as 30 seconds or as long as 30 minutes.[4] Sleepwalking occurs during slow-wave sleep (N3) of non-rapid eye movement sleep (NREM sleep) cycles. Sleepwalking typically occurs within the first third of the night when slow wave sleep is most prominent.[9] Usually, if sleepwalking occurs at all, it will only occur once in a night.[4]