A particular kind of sleep myoclonus is hypnic jerks. The jerking motions the body makes when sleeping or about to fall asleep are known by this scientific term. To understand more in detail, The Pioneer’s Tejal Sinha connects with experts to provide a detailed analysis of the hypnic jerks.
Just after falling asleep, you may have woken up with a sudden jerking movement. It is believed that the mental image or explanation comes after the movements, which could be the result of an electrical discharge along the body’s nerves. To explain the movement, the brain sort of tells a story.
According to a report published by the National Center for Biotechnology Information, hypnic jerks are considered parasomnias and are classified as sleep-wake transition disorders. Although hypnic jerks are considered a benign sleep or movement disorder, some of the latest research indicates that they may be a clinical characteristic for other sleep disorders that affect health care outcomes!
Hypnic jerks, also known as sleep starts, are involuntary muscle twitches that occur as a person transitions from wakefulness to sleep. Approximately 60–70% of people experience these sensations, which often resemble the feeling of falling, leading to a sudden awakening. While the exact cause of hypnic jerks is unknown, they are commonly associated with anxiety, caffeine, stress, and strenuous activities before bedtime. These are usually harmless jerks, are a part of the natural sleep process, and do not usually necessitate medical intervention unless they frequently disrupt sleep and lead to significant sleep disturbance.
Dr. Shiva Kumar R, Head and Senior Consultant, Neurology, Manipal Hospital, shares, “Everyone experiences sleep starts. Hypnic jerks, also called sleep starts, are painless, involuntary movements noted as one falls asleep. Hypnic jerks are a type of movement called myoclonus, which is a category of rapid, involuntary muscle movements such as jerking or twitching. Extremely common and seen in more than 70% of individuals. It can occur at any age but is often seen in young people, probably due to elevated stress levels. These jerks or twitches are painless but can trigger a startle-like response and cause vigorous movements, sometimes disturbing the bed partner or awakening the person from sleep. Hypnic jerks usually affect one side of the body, like the arm or leg. One may experience a single jerk or multiple jerks in succession. In addition to these jerks, one may experience a dream or a hallucination, like seeing flashes or hearing crackling or snapping sounds.”
Hypnic jerks occurring at the onset of sleep have several associated causes:
Stress and anxiety: High levels of emotional or mental stress can increase the frequency of hypnic jerks.
Caffeine: Consuming caffeine close to bedtime can stimulate the nervous system and potentially trigger these twitches.
Strenuous nighttime activities: Engaging in vigorous physical activities late in the day can overstimulate the body, leading to sleep disruptions like hypnic jerks.
Stimulant medications: Certain medications, especially those that act as stimulants, can exacerbate the incidence of hypnic jerks.
Hypnic jerks and age groups
“Hypnic jerks can occur in individuals of any age, but they are most observed in young adults and otherwise healthy people. There is no specific age group uniquely predisposed to experiencing these muscle twitches as they transition into sleep. However, factors such as stress levels, lifestyle habits (like caffeine intake and physical activity), and overall sleep health, which can vary widely among different age groups, may influence their frequency and intensity,” explains Dr. Mona Dahiya, Senior IVF Consultant, Little Angel IVF.
Meanwhile, Dr. Nivedita Kumar, BDS, MS, and Sleep Medicine Specialist in association with Magniflex India , too, explains that hypnic jerks can occur in people of any age but are most commonly experienced by adolescents and young adults. Although it can also occur among older adults, “Hypnic jerks can wake us up, particularly if they are accompanied by a sensation of falling or if they cause a significant muscle contraction. The exact mechanism behind why hypnic jerks sometimes wake us up isn’t fully understood, but it may involve a sudden disruption of the transition from wakefulness to sleep,” she further explains.
Difference between Hypnagogic vs. Hypnic Jerks
Dr. Mona shares that hypnagogic jerks and hypnic jerks often get confused due to their similar sounding names and association with sleep, but they refer to different phenomena.
Hypnic Jerks:
Definition: Hypnic jerks, also known simply as sleep starts, are sudden, brief, and involuntary muscle twitches that occur as a person falls asleep.
Sensation: Often accompanied by a sensation of falling or a startle response, causing the sleeper to wake up momentarily.
Cause: thought to be caused by factors such as stress, caffeine, fatigue, and strenuous nighttime activities.
Hypnagogic Phenomena:
Definition: Hypnagogic refers to the transitional state from wakefulness to sleep, right before sleep onset.
Sensation: characterised by vivid sensory experiences such as visual, auditory, or tactile hallucinations. People might see geometric patterns, hear sounds, or feel as if they are falling or floating.
Cause: These phenomena occur due to the brain transitioning into sleep mode and are not necessarily linked to external lifestyle factors like hypnic jerks.
In summary, while both occur at the onset of sleep, hypnic jerks are physical twitches that can abruptly wake you, whereas hypnagogic phenomena involve more of a sensory and perceptual experience during the drift into sleep.
“Hypnic jerks are generally considered harmless and are a normal part of the sleep process for many people. However, it can sometimes disrupt sleep or cause discomfort, particularly if it occurs frequently or is accompanied by other sleep disturbances. If hypnic jerks are significantly affecting your sleep or daily life, consider seeing a healthcare professional or a sleep specialist (Somnologist) for further evaluation and treatment,” highlights Dr. Nivedita.
Preventing hypnic jerks can be challenging, but adopting healthy sleep habits can help reduce their frequency. Here are a few tips:
1. Establish a regular sleep cycle: Maintaining a consistent sleep schedule is important for regulating the body’s internal clock. It’s recommended to go to bed and wake up at the same time every day, including weekends. Following this can help you maintain a healthy sleep routine and keep your body clock in check.
2. Limit caffeine and stimulants: Avoid consuming caffeine or other stimulants, especially around bedtime, as they may disrupt your natural sleep process.
3. Practice relaxation techniques: Engage in relaxation techniques such as deep breathing, meditation, or gentle stretching before bedtime to promote relaxation and reduce stress.
4. Create an environment for restful sleep: Ensure your bedroom is sleep-friendly by keeping it cool, dark, and quiet.
However, if one experiences only hypnic jerks, Dr. Shiva Kumar suggests that probably one is required to see a neurologist or a sleep medicine specialist. However, he adds, “If someone has multiple jerks that spread to other parts of the body during the day, it could indicate the presence of other neurological conditions. Some medical disorders that are of concern are periodic limb movements in sleep, which can cause sleep fragmentation and arousal, and excessive daytime sleepiness. Some epilepsy disorders can present with jerks in the early morning or daytime called epileptic myoclonic jerks.”
