• (sleep terror) Episodes of intense fear, screaming, and flailing occur even though the affected individuals are still asleep.
  Human Phenotype Ontology (HPO)
  The Human Phenotype Ontology Project, 2025
• A disorder characterized by incomplete arousals from sleep associated with behavior suggesting extreme fright. This condition primarily affects children and young adults and the individual generally has no recall of the event. Episodes tend to occur during stage III or IV. SOMNAMBULISM is frequently associated with this condition. (Adams et al., Principles of Neurology, 6th ed, p391)
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• Episodes of abrupt awakening associated with screaming, agitation and hyperarousal.
  NCI
  U.S. National Cancer Institute, 2021
• (sleep terror disorder) A sleep disorder characterized by abrupt awakenings from sleep with a panicky scream, accompanied by signs of autonomic arousal. There is no recall of a nightmare and the person has amnesia for the event in the morning.
  NCI
  U.S. National Cancer Institute, 2021
• Sleep disruption in childhood is a common and frequently upsetting occurrence; sleep terrors (also known as night terrors or pavor nocturnus) are a specific sleep disruption most remarkable for their intensity and anxiety-appearing nature. Most episodes begin within the first 1-2 hours of sleep, during stages 3 and 4 of non�rapid eye...
  Medscape
  WebMD, 2025
• Sleep terrors are episodes of screaming, intense fear and flailing while still asleep. Also known as night terrors, sleep terrors often are paired with sleepwalking. Like sleepwalking, sleep terrors are considered a parasomnia - an undesired occurrence during sleep. A sleep terror episode usually lasts from seconds to a few minutes, but...
  Mayo Clinic
  Mayo Foundation for Medical Education and Research, 2025