Hypnic Jerk: Causes behind Twitch Sensation While Falling Asleep

According to some specialists, hypnic jerks are a type of parasomnia – a sleep condition characterised by strange and undesired bodily events.

Written by: Sambhav Kumar Updated at: 2023-03-24 18:28

Hypnic jerks, also known as sleep starts, are involuntary twitches or muscle contractions that can occur during the transition from wakefulness to sleep. They are thought to be caused by a sudden shift in brain activity as the body relaxes into a sleeping state. During a hypnic jerk, the person may experience a sudden, brief jolt of movement or sensation. It may be accompanied by a feeling of falling or being startled.

According to the National Centre for Biotechnology Information, in addition to the jerking movement, a hypnic jerk is often accompanied by other sensations or mental imagery, such as a dream or hallucination. A person frequently reports falling, witnessing flashing or dazzling lights, the sound of slamming, crackling, or snapping. Although some people report a tingling or unpleasant sensation, hypnic jerks are often painless.

According to some specialists, hypnic jerks are a type of parasomnia – a sleep condition characterised by strange and undesired bodily events that disrupt your sleep. The International Classification of Sleep Disorders (ICSD-3) classified hypnic jerks as a sleep-related movement disorder as isolated symptoms. Despite the fact that hypnic jerks are usually harmless, there has been a rise in reports of this disorder in neurological illnesses such as Parkinsonism, migraine, and brainstem lesions, as well as in children with neurologic disorders.

Causes Of Hypnic Jerk

Hypnic jerk, also known as a hypnagogic jerk, is an involuntary twitching or jerking of the body that occurs just as a person is beginning to fall asleep. This type of movement usually occurs in the arms, legs, or entire body, and is usually accompanied by a feeling of falling or a sudden startle.

It is thought that the twitching may be a result of the body’s natural transition from being awake to being asleep. During this transition, the brain may experience a sudden change in electrical activity, which can cause the muscles to twitch.

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Another possible cause of hypnic jerks is stress. Stress can interfere with the body’s ability to relax and fall asleep, which can cause the body to experience involuntary spasms and jerks.

Other factors that may contribute to hypnic jerks include a lack of sleep, caffeine, alcohol, medication, and certain medical conditions such as narcolepsy. In some cases, hypnic jerks may be a sign of an underlying medical condition that should be evaluated by a doctor.

Symptoms Of Hypnic Jerk

Hypnic jerks are involuntary spasms that can startle you awake. Symptoms of hypnic jerks may include:

  • Feeling like you are falling or jolting awake
  • Feeling like your body is shaking
  • An inability to stay asleep 
  • A racing heart
  • A feeling of anxiety 
  • An uncomfortable sensation in the chest or stomach
  • Difficulty in breathing
  • Sweating
  • A feeling of being paralyzed 
  • Crying out in sleep
  • Brief muscle spasms in the legs, arms, or face 

Most people experience hypnic jerks without any adverse effects, but in some cases, they can be a sign of an underlying medical condition such as narcolepsy or sleep apnea. If you experience hypnic jerks frequently or if they are accompanied by other symptoms, it is important to talk to your doctor.

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Despite the fact that hypnic jerks are common and usually harmless, they can be a nuisance to some people and can interfere with sleep. People who experience frequent or intense hypnic jerks may benefit from lifestyle changes and stress management techniques, such as getting adequate sleep, exercising regularly, and practising relaxation techniques like yoga or meditation. In some cases, medications that reduce anxiety or promote sleep may be recommended.


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