Drowsiness, or narcolepsy, is a sudden, involuntary muscle contraction when you are asleep1. Hypnic jerks are myoclonus2, a type of rapid, involuntary muscle movement. Hiccups3 is another type of myoclonus. Hypnic is short for hypnagogic4 and describes the transition from wakefulness to sleep when these shocks occur.
What do Hypnic Jerks feel like?
Hypnic shocks happen randomly while you’re sleeping and usually affect only one side of your body, such as the left arm or left leg. You may have one or several strokes in a row before your body relaxes again.
In addition to sudden movements, it is common to experience other sensations and mental images, such as dreams and hallucinations, along with feelings of sadness. People often feel as if they are falling, see flashing or flashing lights5, or hear banging, rattling, or snapping sounds. Most of the time, the numbness is painless, but some people experience tingling and pain.
Hypnic jerks feel different at different times. Sometimes they are strong enough to wake a person up and disrupt the sleep process. In other cases, they are so mild that the affected person does not notice them at all, but the sleeping partner may.
Hypnosis can occur at any age, but is more common in adults. This may be partly because their potential causes, such as caffeine consumption and stress levels, are more common in adulthood.
What Causes Hypnic Jerks?
Researchers aren’t sure what causes hypnic shock, but they have several theories. Hypnic shock and other types of myoclonus start in the same area of your brain that controls your shock response. During sleep, researchers suspect that abnormalities sometimes occur between neurons in the reticular brainstem, which can lead to sleepiness.
For example, when your muscles are completely relaxed, it’s normal to fall asleep, but your brain mistakenly thinks you’re actually falling and reacts by tensing up your muscles. And hypnosis may be a physical response to the dreamlike imagery that accompanies them.
Some risk factors can make you more likely to become drowsy, including excessive caffeine and stimulant use, vigorous exercise before bed, emotional stress, and poor sleep.
Excessive use of caffeine or nicotine
Stimulants like caffeine and nicotine wake up your brain6. These substances can stay in your system for hours, disrupting sleep. One study found that people who stopped drinking coffee six hours before bed still couldn’t fall asleep. Consuming too much caffeine or nicotine, or consuming these substances too close to bedtime, can cause drowsiness.
Vigorous exercise at night
In general, exercising to sleep is almost always a good idea. Regular exercise8 has been shown to improve sleep quality. However, it’s important to understand that exercise is not exhausting, but an energizing activity that makes you feel more alert. This is why too much exercise in the evening can make you sleepy.
Lack of sleep
Insomnia due to chronic lack of sleep or poor sleep, and regular insomnia can both lead to insomnia. Among the unwanted side effects of poor mood and concentration, lack of sleep increases the risk of sleepiness.
Stress and anxiety
Everyday stress9 and diagnosed anxiety disorders10 both contribute to insomnia, which in turn leads to insomnia, which increases the risk of falling asleep. When you’re stressed or anxious, your cortisol levels remain high during sleep, which doesn’t make for restful sleep. Anxious thoughts can keep you up at night, make it difficult to fall asleep, disrupt the transition between wakefulness and sleep, and induce hypnosis.
Some people experience constant anxiety during sleep, which increases the likelihood of insomnia and sleepiness.