We’ve all been there. You’re just drifting off to sleep when seemingly out of the blue, your body jerks you back to wakefulness once more. Although they are extremely common (it’s estimated that up to 70% of people experience them regularly), these starts – also known as ‘hypnic jerks’ – can be alarming. So, what causes them? And can they be stopped? Here, we take a closer look at how you could get your hypnic jerks under control…
What are hypnic jerks? Hypnic jerks occur when your muscles – usually the leg muscles – involuntarily contract and, although there is no concrete explanation for why they occur, there are several theories as to what could be causing them.
The muscle spasms may occur spontaneously or may be induced by sound, light or other external stimuli. Some people report hypnic jerks accompanied by hallucinations, dreams, the sensation of falling, or bright lights or loud noises coming from inside the head.
Some scientists believe certain factors, such as stress, anxiety, fatigue, caffeine, and sleep deprivation, may increase the frequency or severity of hypnic jerks, but conclusive research is lacking on the subject. Intense physical activity or exercise in the evening may also contribute to increased hypnic jerks, said Michelle Drerup, a psychologist and behavioral sleep medicine specialist at the Cleveland Clinic’s Sleep Disorders Center in Ohio۔
