Somnambulism, or sleepwalking, is a commonly known parasomnia that is not completely understood. Episodes may start similar to confusional arousal while sitting up and looking around confusedly, but the affected person will then get up from bed and continue to perform more complex and seemingly goal-directed actions. These can include walking, running, jumping, cleaning, cooking, eating, and even driving. Sleepwalkers may commonly injure themselves or others. The person may wake up spontaneously when sleepwalking, or return to bed while still asleep . If woken up while sleepwalking, they can become agitated or aggressive. Most sleepwalkers have no memories of the episode. Like confusional arousal, sleepwalking occurs during the first part of sleep, during NREM sleep.