Confusional Arousals And Waking Up Halfway

Someone sits up, speaks in a way that makes little sense, and remembers none of it in the morning. This is a confusional arousal, the most common of the non-REM parasomnias.

What the episode looks like

The person appears awake with eyes open, may sit up or reach for something, and often responds to questions with slow or garbled speech.

They do not leave the bed, which is the main feature separating this from sleepwalking, and the episode usually lasts from a few seconds to several minutes.

Attempts to rouse them fully tend to prolong the confusion, and some people become irritable or resistant when pressed.

The state underneath

These episodes arise from incomplete transitions out of deep non-REM sleep, in which motor and speech systems activate while regions supporting awareness stay asleep.

Because memory formation depends on structures that remain offline, the person retains nothing afterward and may not believe the account they are given.

They occur predominantly in the first third of the night, when deep sleep is concentrated, which distinguishes them from nightmares arriving late in the night.

Who experiences them

They are extremely common in young children, and a child who wakes disoriented and inconsolable is usually experiencing this rather than a nightmare.

Frequency declines through childhood, though a proportion of adults continue to have them, and there is often a family history of one parasomnia or another.

Episodes concentrated around waking are sometimes called sleep drunkenness, which overlaps with the ordinary grogginess of sleep inertia and blurs the boundary.

What makes them more likely

Sleep deprivation increases the depth and pressure of non-REM sleep, and rebound after short nights is a frequent trigger.

Anything causing arousals during deep sleep contributes, including untreated sleep apnea, a full bladder, noise, fever and an unfamiliar room.

Alcohol and some sedatives change the architecture of early-night sleep and are commonly reported in association with episodes in adults.

When it needs attention

Isolated episodes in a child who is otherwise well are ordinary, and reassurance plus a stable sleep schedule is usually the whole of the response.

Frequent episodes, injury, or behavior during them that is aggressive or complex warrant evaluation, both to check for an underlying disorder and because forensic questions occasionally arise.

A sleep physician can distinguish these from nocturnal seizures, which can look similar to a bed partner, and that distinction is not one to attempt at home.