- Richard Jones, Swansea, South Wales THE "hypnic jerk
" is an involuntary muscle spasm that usually occurs just as we're falling asleep.
This strange sensation and muscle twitch is known as a hypnagogic myoclonic twitch or hypnic jerk
and often happens as people are falling asleep.
THIS strange falling sensation and muscle twitch is known as a hypnagogic myoclonic twitch or " hypnic jerk" If this has happened to you on more than one occasion, don't worry, you are not alone.
While this phenomenon happens to everyone, studies have recently begun to link occurrences of " hypnic jerks" to sleep anxiety, fatigue, and discomfort.
FFI is a hereditary autosomal dominant prion disease, which is mainly characterized by prominent sleep impairment accompanied by a series of neuropsychiatric disorders, dysautonomia, motor dysfunction, and episodes of peculiar oneiric behaviors (oneiric stupor). Irregular breathing, hypnic jerks, propriospinal myoclonus at the wake-sleep transition, and quasi-purposeful limb gestures are considered to be core features of FFI.
The most prominent clinical manifestation is sleep disturbance, which includes insomnia, laryngeal stridor, sleep breath disturbance, oneiric or stuporous episodes with hallucinations and confusion, and sleep-related involuntary movements (such as hypnic jerks, restless sleep with frequent changes in body position, and twitchy nonpurposeful movement of limbs).
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).
RLS or hypnic jerks? Many individuals experience brief jerking movements (hypnic jerks) at the onset of sleep.