Today in Body Weird: If you have a sudden, jarring muscle spasm-type jerk right before you fall asleep, that weird sensation that makes you feel like you’re falling, you are not alone. It’s a very common occurrence and now it has a name — actually, it has two. Hypnic jerks, or sleep starts, happen when “a sudden increase in muscle activity” takes place just as your body is calming itself down for a long night’s sleep. Carl Bazil, M.D. Ph.D., director of the Sleep Disorders Center at New York–Presbyterian/Columbia University Medical Center and a neurology professor, says that the level of intensity of sleep starts vary between people, but no matter how subtle or strong they are, they’re perfectly normal.
“One of the things that happens as you fall asleep is your muscles relax, but the awake part may still be stimulating enough that it will temporarily overreact and you get this jerk of muscle activity,” he says.
Oftentimes, a sleep start can feel like the end of a dream (or nightmare) in which the person is falling, but there is no explanation or reason why some people experience visions in addition to this harmless phenomenon. If it happens to you, you can brush it off as a full-body hiccup — annoying, but nothing to worry about. They could even be occurring without you noticing and be as dramatic as something that can make you scream. But again, totally normal!
Here’s the good news: there is a way to avoid sleep starts. For some of us, it might be easier said than done, but the most sure-fire ways to get more restful, less animated sleep is to avoid excessive caffeine and/or other stimulants (such as tobacco or medications like Adderall) and try to sleep more. But if the thought of experiencing the physical sensation of falling is keeping you up at night to begin with, then the best advice is to stop worrying about it.
Just another case of your body being a jerk, literally.
Source: The Cut