Many people experience a sudden feeling of falling as they are about to fall asleep and wake up with a start. This can sometimes cause a rapid heartbeat and a brief feeling of fear. People experiencing this for the first time might perceive it as dangerous or abnormal. However, this sensation is quite common in the human body and is generally harmless.
The feeling of falling while sleeping is what scientists call hypnic jerks (or hypnagogic jerks) or myoclonic jerks. Hypnic jerks are also known as sleep starts. These are strong, involuntary muscle contractions that usually occur while falling asleep. This sudden movement in the body can startle a person awake during the transition between wakefulness and sleep. Scientists are not entirely sure why this happens, but there are several theories.
One theory suggests that the brain misinterprets muscle relaxation that occurs before sleep. Muscle relaxation is normal, but the brain may briefly interpret it as falling. In response, the brain causes the muscles to contract suddenly in an attempt to protect the body, resulting in jerky movements.
Several risk factors can increase the likelihood of experiencing hypnic jerks. Stimulants such as caffeine and nicotine, especially when consumed in excessive amounts or before bedtime, can disrupt sleep patterns and increase the risk. Although caffeine may temporarily help a person stay awake, excessive use negatively affects sleep quality.
Intense exercise late at night may also contribute to hypnic jerks. Regular exercise improves sleep quality, but vigorous activity before bedtime increases alertness and delays sleep onset.
Sleep deprivation is another important factor. Chronic insomnia, irregular sleep schedules, or insufficient sleep can increase the risk of hypnic jerks. In addition, stress and anxiety can contribute to sleep problems. High stress levels increase cortisol levels, making sleep less restful and disrupting the natural transition between wakefulness and sleep.
In most cases, hypnic jerks are harmless and part of the normal sleep process. However, frequent or severe hypnic jerks may sometimes be associated with sleep disorders such as Periodic Limb Movement Disorder (PLMD), REM Sleep Behavior Disorder (RBD), seizure disorders, or sleep apnea.
In conclusion, the sensation of falling while sleeping is a normal and harmless condition experienced by many people. It is usually caused by stress, fatigue, sleep deprivation, or stimulant use. Maintaining a regular sleep schedule, reducing stress, and avoiding caffeine before bedtime can help reduce this sensation. If it occurs frequently and significantly affects sleep quality, medical consultation may be necessary. However, in most cases, it is a natural bodily response and not a cause for concern.
References
Medicana Health Group. (2023). Why does falling sensation occur while sleeping? medicana.com.tr
Sleep Foundation Editorial Team. (2024). Hypnic jerks: Why you twitch when falling asleep. sleepfoundation.org
National Sleep Foundation. (2022). Hypnic jerks and sleep starts. thensf.org
Mayo Clinic Staff. (2023). Sleep starts (hypnic jerks): Symptoms and causes. mayoclinic.org
National Institutes of Health. (2022). Brain basics: Understanding sleep. nih.gov
Cleveland Clinic. (2023). Hypnic jerks: Causes and treatment. my.clevelandclinic.org