hypnic jerk


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hypnic jerk

a brief myoclonic muscle twitch preceding sleep onset.
References in periodicals archive ?
This strange sensation and muscle twitch is known as a hypnagogic myoclonic twitch or hypnic jerk and often happens as people are falling asleep.
He suffered from excessive startle responses and hypnic jerks since the age of 5 years and had several spontaneous spasms and injuries because of frequent drop attack-like episodes, similar to his sister.
As described, Ashley's symptoms could suggest a number of disorders (TABLE): specifically, nocturnal leg cramps (NLC), akathisia, restless legs syndrome (RLS), peripheral polyneuropathy, hypnic jerks or sleep starts, and periodic limb movements in sleep (PLMs).
Hypnic jerks occur primarily in the legs or arms but can involve the whole body.