Hypnic Jerks

Hypnic jerks are basically involuntary sleep movements that occur as you transition from wakefulness to sleep. They are sometimes referred to as hypnagogic jerks or sleep starts. They are not very well understood, however, they do tend to occur more often when you’re trying to force your brain to engage in an activity when you’re sleep-deprived. Rafael Pelayo, a sleep specialist at the Stanford Sleep Medicine Center, says that it’s because certain parts of your nervous system are awake, while others are asleep.

Essentially, you can think of a hypnic jerk as a misfire caused by your nervous system sending your body mixed messages. Generally, they occur when you’re transitioning from wakefulness into stage one of sleep. As explained, REM sleep typically occurs ninety minutes after falling asleep. When you’re really sleep-deprived, however, you go straight from stage one to REM sleep. You basically skip right over stages two and three. Paleyo says that a hypnic jerk is a clear sign from the body that you need to sleep. “Nothing else is going to satisfy that urge.”

Are Hypnic Jerks Dangerous?

Luckily, no. Hypnic jerks, while they can be scary at the moment, are benign and do not need to be treated. Some may feel anxious after experiencing one and have difficulty falling back to sleep. If this happens to you, try to remind yourself that it doesn’t mean anything and that there’s nothing wrong. This may help to ease your mind so you can go back to sleep.

Hypnic Jerks and Lack of Sleep

Sometimes, though, you may experience a hypnic jerk when sleep is not an option. For some, they can occur when they’re over tired in a class lecture or a meeting. If this is the case, Palayo has a few suggestions:

• Focus on something that’s more important about that scenario than falling asleep.
• Make eye contact with the speaker.
• Drink coffee beforehand if you know you’re going to have trouble staying alert.
• Make sure to get seven to nine hours of sleep every night to avoid being over-tired.

While hypnic jerks are not dangerous, they are a sign that you’re not getting enough sleep. If you notice them happening frequently, ask yourself why you might be over-tired and consider making some changes.