Confusional arousals occur when the brain becomes divided, literally, between sleeping and waking.
Part of the brain wakes up, but another part remains deeply asleep. A sleep-walker's behavior may be calm or it may be agitated. Occasionally it can be violent. If a sleep-walker risks injuring him or herself, treatment for the disorder should be sought immediately from a specialist in sleep medicine. When children experience confusional arousals, they typically awaken frightened and confused, and often scream in terror at an invisible threat.