Night terrors
Also called: Sleep terrors · Pavor nocturnus
A sleeping child suddenly sits up, screams, and looks terrified, but is not awake. Parts of the brain act awake while the rest stays in deep sleep. Next morning the child usually remembers nothing. The parent remembers all of it.
How common
Does this happen to you?
How it works
A night terror starts suddenly. The sleeper bolts upright with wide eyes, screams, and may thrash or run1. The heart races, breathing is fast, and the skin sweats15. The person looks awake but is not. They cannot be comforted and may not recognise people they know12. An episode lasts up to about 15 minutes2. Then the sleeper settles back to sleep5. Next morning they usually remember nothing2.
The medical term is sleep terror, or pavor nocturnus. It comes out of slow-wave sleep, the deepest stage of non-dreaming (NREM) sleep1. Most episodes happen in the first third of the night5.
During an episode the brain is in a mixed state. Recordings from night terrors and sleepwalking show that areas for movement and emotion act as if awake. At the same time, a network across the front and top of the brain stays in deep sleep3. Researchers compare this to “local arousal”, where only some parts of the brain wake up3. The old idea of total memory loss is now questioned. Some people recall a brief image or fragment13.
A night terror is not a very bad nightmare. A nightmare is a dream in REM sleep, later in the night. You wake up from it and remember it12. Night terrors run in families and are closely linked to sleepwalking12. In one study, as many as one-third of children with early night terrors later started to sleepwalk4. Lack of sleep, fever, and stress make episodes more likely1.
How common it is
The top figure is for young children only. In a Quebec study of 1,940 children, sleep terrors peaked at 18 months. Mothers reported them in 34.4% of children at that age4. In the same group, 39.8% had them at some point between ages 2.5 and 66. Most children outgrow them by about age 105. In adults the rate is much lower1. A UK telephone survey of 4,972 teenagers and adults found 2.2%7. The authors say self-reports probably undercount it7. All the child figures come from mothers’ reports.
Is it a problem?
In young children, usually no. Most children grow out of night terrors5. They do not raise a child’s chance of epilepsy5. Running or thrashing can cause injury1. The NHS advice is to stay calm and not wake the person. Do not hold them back unless they could hurt themselves or someone else2.
See a doctor if:
- a child still has night terrors after age 122,
- night terrors start after age 52,
- night terrors start in adulthood, which is rare5.
Some night-time seizures look similar5.
Sources and further material
- Wikipedia Night terror Symptoms, difference from nightmares, and DSM-5 figures: 36.9% of children at 18 months, 19.7% at 30 months.
- nhs.uk Night terrors and nightmares Ages 3 to 8, episodes of up to 15 minutes, what to do during one, and when to see a GP.
- PubMed Sleepwalking, sleep terrors, sexsomnia and other disorders of arousal: the old and the new Journal of Sleep Research. Review. Wake-like motor and emotion regions next to deep sleep in a front and top network. 2% to 4% of adults have a disorder of this group.
- PubMed Childhood Sleepwalking and Sleep Terrors: A Longitudinal Study of Prevalence and Familial Aggregation JAMA Pediatrics. 1,940 Quebec children. Peak of 34.4% at 18 months. As many as one-third of children with early sleep terrors later sleepwalked.
- NCBI Night Terrors First third of the night, look-alike seizures, no raised risk of epilepsy, most children outgrow it by age 10.
More sources for this oddity (2)
- PubMed Dyssomnias and parasomnias in early childhood Pediatrics. 39.8% of Quebec children had sleep terrors at some point between ages 2.5 and 6, by mother's report.
- PubMed Night terrors, sleepwalking, and confusional arousals in the general population: their frequency and relationship to other sleep and mental disorders Journal of Clinical Psychiatry. Telephone interviews with 4,972 people from the UK general population, teenagers included. 2.2% reported night terrors.
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