Science has found out why up to 70% of people jerk while sleeping 0 11

“The condition when a person falls asleep and suddenly jerks or feels a sensation of falling is called a ‘hypnagogic jerk’ (or ‘hypnic jerk’). A hypnagogic jerk occurs due to a sudden involuntary muscle contraction at the moment of transition from wakefulness to sleep and is usually accompanied by a sensation of falling, a feeling of stumbling or tripping, a sudden ‘drop’, and sometimes a bright flash or a brief dream image,” explains Karine Badalyan, an associate professor at the Department of Neurology at Pirogov University.

According to the specialist, jerking during sleep is a common and completely normal phenomenon. There are several explanations for this condition. One of them is related to the so-called ‘mode switching’ of the brain. When you fall asleep, your muscles begin to relax, breathing slows down, and pulse decreases. Sometimes the brain interprets this sudden relaxation as a loss of balance – as if the body is falling. In response, it sends an impulse to the muscles to ‘save’ you. This is a kind of ancient protective mechanism.

Another mechanism is related to a synchronization failure between the central nervous system and the body. Falling asleep is a complex neurophysiological process. There are situations when the brain is almost ‘asleep’, but the motor system is still active; in such cases, a short electrical discharge occurs in the muscles.

“Hypnagogic jerks occur more often during stress, anxiety, sleep deprivation, overwork, and also when consuming caffeine before sleep,” noted Badalyan. “These conditions are absolutely not dangerous and occur in about 60-70% of people. However, if the ‘falls’ are very frequent and interfere with sleep, or if there is a convulsive syndrome, suspicion of epilepsy, or other neurological disorders, then this is a reason to consult a doctor.”

Additionally, during sleep, the brain processes, sorts, and optimizes information, tuning and strengthening memory function. “Sleep consists of phases, each of which serves its purpose. In deep (slow) sleep, the brain transfers important information from short-term memory, associated with the hippocampus, to the long-term storage of the cerebral cortex. During this process, weak and insignificant neural connections are weakened, and a kind of ‘cleaning of extraneous noise’ occurs. In the REM sleep phase, when we see dreams, emotions are actively processed, new connections between events are formed, and experiences are integrated into overall life experience,” Badalyan explained.

In addition to memory processing, physical ‘cleaning’ of the brain is activated during sleep. The dynamic system of cerebrospinal fluid circulation – the glymphatic system – works to eliminate metabolic waste products, including potentially toxic proteins such as beta-amyloid.

“This is why full sleep is not just rest, but a biologically necessary process for maintaining the brain,” emphasizes the specialist.