Hypnic jerk
ConceptSymptoms and Signs
Involuntary muscle contraction at sleep onset
2.50Epic
Epic
Hypnic jerk
- Symptoms and Signs
A hypnic jerk is a brief, sudden involuntary muscle contraction that occurs as a person begins to fall asleep. It can cause a person to jump awake and may resemble the response to being startled, sometimes with a falling sensation. Hypnic jerks are a form of myoclonus and are generally benign. Frequent, severe episodes have been reported to affect sleep onset, sleep time and sleep quality.
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- Classification
- A form of myoclonus
- Occurrence
- When a person is beginning to fall asleep
- Lifetime experience
- Around 70% of people experience them at least once
Sources and credits
Sources and credits
- Article
- Hypnic jerk (English Wikipedia)
- Wikidata
- Q1308944
- Text
- Card text is adapted from the English Wikipedia article by an automated summary. Wikipedia content is available under CC BY-SA 4.0; see the article history for its contributors. CC BY-SA 4.0 · Article history and contributors
- Illustration
- AI-generated illustration. Not a photograph or documentary image. (model: gpt-image-2.5-flare)
- Popularity
- 629 median daily views (Wikimedia Pageviews API (all-access, user agent))
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