These typically occur in non-REM sleep, especially in the deeper stages (slow wave sleep). All are more common in children, and occur more frequently whenever sleep is deeper (such as after sleep deprivation). Confusional arousals (“sleep drunkenness”) consists of confusion, sometimes accompanied by stumbling and slurring, on awakening and can last for several minutes. Sometimes there will be no memory of the awakening whatsoever. Sleep terrors consist of sudden awakening, often accompanied by screaming and a brief, frightening image. In this case the person may also be confused and disoriented for several minutes. Sleepwalking is also considered a disorder of arousal.