yes, therapy helps!
Hypnical myoclonias: what they are and why they appear

Hypnical myoclonias: what they are and why they appear

June 16, 2024

We are peacefully asleep and, suddenly, we feel that we fall from the bed or from the place where we are resting . However, when we open our eyes, due to the shock, we realize that not even we have just moved from the site.

This is exactly what happens when a person he experiences a hypnic myoclonus. Sudden and uncontrollable movements that, despite not posing a risk to health, can become highly annoying and disturbing.

  • Related article: "The 7 main sleep disorders"

What are hypnic myoclonias?

A myoclonus consists of a muscular movement of abrupt and sudden nature , of short duration and that is not subject to the will of the person. Furthermore, in the specific case of hypnic myoclonias, these shakings appear just as we move from a waking state to the first phase of sleep.


As a general rule, only one of these hypnic myoclonias appears asymmetrically, the person has the feeling that he is falling . This perception of falling causes the person to wake up automatically and with a startling sensation.

Since the jolts can become really strong and momentarily cause some anguish in the person who suffers them, hypnic myoclonus is not considered a serious pathology.

These events, which appear in approximately 70% of the general population, they do not usually pose a risk to health and you are considering it as a benign sleep disorder. Moreover, in some cases in which they appear in a timely manner, they are seen as something perfectly normal. An own event of the process of passing from wakefulness to sleep.


In these specific cases, myoclonus appears due to changes in respiration, decreased heart rate, muscle relaxation and changes in temperature typical of sleep cycles.

This curious phenomenon becomes increasingly interesting when we know that hypnic myoclonias appear because, by lowering our pulsations considerably, our brain interprets it as a sign of death, so it sends a powerful nervous impulse to try to revive the body.

  • Maybe you're interested: "10 basic principles for good sleep hygiene"

What causes them?

For the time being, it has not yet been possible to determine what factors cause these hypnic myoclonus. That is, what internal or external agents they unleash that strong cerebral and muscular impulse .

However, it has been discovered that there are some conditioning factors that can considerably increase the possibility that these myoclonus or jerking appear:


  • During times of stress, as well as the experimentation of both temporary and prolonged anxiety increases the possibility of myoclonus appearing during sleep.
  • Performing physical activities of great impact, which involve significant muscle fatigue or wear can also favor the appearance of these sudden movements. This could be due to a deficit of calcium, magnesium and iron.
  • Consumption of alcohol and caffeine during the night can increase the possibility of suffering these shakings.
  • Certain medications or drugs that affect the nervous system can also enhance hypnic myoclonus.
  • Finally, we are investigating how lack of sleep as well as rest in complicated or uncomfortable postures affects this phenomenon.

When do they appear?

The hypnotic myoclonus is an eventuality typical of the sleep processes that appear when entering the first phase of this, when we abandon the waking state and begin the first sleep cycle.

In addition, if we are especially tired, this change between one state and another takes place more quickly. So, even though our muscles are very relaxed, our brain still remains active, and When the sensation of falling appears, our brain generates an impulse to keep us alert .

Although this sensation in which we seem to fall is lived as if it were a dream, since we experience it when we are almost asleep, this event or peculiarity is not considered as such. The reason is that dreams, as we know them, only occur during the last phase of the dream; that is, the REM phase.

How can we avoid it?

As we have mentioned previously, the experimentation of these hypnic myoclonias does not pose a risk to our health. However when they appear more recurrently it can generate a great sensation of disturbance and restlessness.

Next we will see a series of recommendations to avoid these shakes.However, if they appear very frequently and even more than once during the night, it is advisable to go to a neurology specialist .

  • Decrease levels of anxiety or stress with activities that we find pleasurable or through relaxation or meditation exercises.
  • Perform relaxing activities before bedtime . Such as a hot bath, light readings, etc.
  • Do not exercise excessively, at least six hours before going to bed.
  • Sleep the recommended 8 hours of sleep. In addition, trying to maintain a constant sleep schedule.
  • Do not consume alcoholic or caffeinated beverages before going to bed.
  • Maintain a varied diet that provides the sufficient amounts of magnesium and calcium that our body needs.
Similar Articles