They are opposite events. Deep slow-wave sleep runs the first third of the night; dreaming REM fills the second half. A terror is a botched exit from slow-wave sleep: the parts that scream and race the heart switch on while the parts that recognise you and record memories stay off. The child is technically still asleep, which is why nothing survives to morning 1. A nightmare is a REM dream that wakes the child, who then knows you and remembers it 2.
Four signals tell them apart. Timing: terrors hit in the first one to three hours, nightmares in the second half. Arousal: a child mid-terror won't respond to their name; a child after a nightmare locks eyes and reaches for you. Memory: none after a terror, usually vivid after a nightmare. Consolation: a terror runs its course no matter what you do, a nightmare calms once you're there.
Both are common and both fade. Terrors peak near age 1.5 and drop under 10% by school age 3. Nightmares peak between 6 and 10; the weekly kind hits about 5% of school-age children and tracks with daytime stress 4.
During a terror, do nothing active. The instinct to wake and soothe is the one thing that makes it worse.
The gain lands fast.
- Days to weeks: scheduled awakenings break predictable nightly terrors in most children 6, 8.
- Weeks: the rehearsed dream is the one that surfaces; nightmare frequency and distress drop 9.
- Within a month: the parent stops bracing for the midnight scream, the child stops dreading bedtime, and the afternoon edge of a household on broken sleep softens.
The fine print โ when to skip it, and what people get wrong
See a doctor for loud snoring or breathing pauses with terrors 10, daytime sleepiness despite full hours, injury during episodes, adolescent onset, or nightmares tied to trauma.
"It's a bad dream, wake them up." Both halves are wrong: it's usually a terror, and waking prolongs it 1. Terrors in young kids rarely mean a psychological problem 4.
Where it goes wrong: treating a terror like a nightmare or the reverse; missing a snoring child's airway 10; and reaching for melatonin before sleep hygiene and the two routines above have had a few weeks.
- 1Mason TB, Pack AI (2007). Pediatric parasomnias. Sleep. link
- 2Levin R, Nielsen TA (2007). Disturbed dreaming, posttraumatic stress disorder, and affect distress: a review and neurocognitive model. Psychological Bulletin. link
- 3Petit D, Pennestri MH, Paquet J, Desautels A, Zadra A, Vitaro F, Tremblay RE, Boivin M, Montplaisir J (2015). Childhood Sleepwalking and Sleep Terrors: A Longitudinal Study of Prevalence and Familial Aggregation. JAMA Pediatrics. link
- 4Schredl M, Fricke-Oerkermann L, Mitschke A, Wiater A, Lehmkuhl G (2009). Longitudinal study of nightmares in children: stability and effect of emotional symptoms. Child Psychiatry and Human Development. link
- 5Carter KA, Hathaway NE, Lettieri CF (2014). Common sleep disorders in children. American Family Physician. link
- 6Lask B (1988). Novel and non-toxic treatment for night terrors. BMJ. link
- 7Krakow B, Hollifield M, Johnston L, et al. (2001). Imagery rehearsal therapy for chronic nightmares in sexual assault survivors with posttraumatic stress disorder: a randomized controlled trial. JAMA. link
- 8Durand VM, Mindell JA (1990). Behavioral treatment of multiple childhood sleep disorders. Effects on child and family. Behavior Modification. link
- 9Simard V, Nielsen TA (2009). Adaptation of imagery rehearsal therapy for nightmares in children: a brief report. Psychotherapy. link
- 10Guilleminault C, Palombini L, Pelayo R, Chervin RD (2003). Sleepwalking and sleep terrors in prepubertal children: what triggers them? Pediatrics. link