What Exactly Is a Hypnic Jerk?
A hypnic jerk is a brief, involuntary muscle contraction that occurs as you are falling asleep.
It can affect one part of the body, such as a leg or arm, or involve several muscle groups at once. Some people describe it as feeling like they are falling, stumbling, tripping, or suddenly being pushed.
Others experience a quick sensation that resembles an electric shock or a sudden jolt through the body.
The movement usually lasts only a fraction of a second.
Although researchers do not know exactly why every hypnic jerk occurs, one explanation is that your brain and body are going through a rapid transition from wakefulness to sleep. As your muscles relax and your nervous system changes its activity, the brain may occasionally send a brief signal that produces a sudden contraction.
In most healthy people, occasional hypnic jerks are harmless.
Why Does It Feel Like You’re Falling?
One of the strangest aspects of a hypnic jerk is the sensation of falling.
