9 times out of ten, just when I am in that place just before drifting off, I have a shutter-spasm-like thing happen. What causes this, and what is it called?
2007-08-27 13:46:13 · 7 answers · asked by polyoctonomy 1 in Health ➔ General Health Care ➔ Other - General Health Care
This is called a hypnic or myoclonic jerk.
When you fall asleep, normally your body temperature goes down and your heart starts to beat just a little slower. This is because your brain signals your body to relax to prepare for sleep. When your muscles are relaxed, you go into the very first stages of sleep, but you're not sleeping too deeply yet.
This brain activity may cause your larger muscles to contract a little bit. In response, another part of your brain will make up a very quick mini-dream to go along with what is happening. You might think this would take a while, but your brain works so lightning fast that it makes up the story almost at the same instant that your muscles jerk.
During this light sleep, you can be easily awakened - like if the phone rings or if your dog licks your face. A lot of people who do wake up during this light sleep believe they haven't really fallen asleep yet. That's why you may think that your body jerked right before you were about to fall asleep, but really, you were lightly asleep the whole time - just not deeply asleep.
Myoclonic jerks are a normal part of sleep. Most people (80%) have them at one time or another. But many people do not realize their muscles are jerking at times during light sleep and it doesn't wake them up.
Hope that helps!
2007-08-27 14:31:05 · answer #1 · answered by A Canadian 6 · 0⤊ 0⤋
Well, poly, I don't really know. But, here is my guess (and guess is a very appropriate word!):
Even when you're asleep, your body maintains a slight amount of muscle tone; a slight tension on the muscles. It's much less than when you are awake.
But as you transition from a waking state to a sleeping state your muscles begin to relax and it is my (unqualified) opinion that on occasion the muscles relax a bit too much and your brain catches this and "snaps" the muscles back to their proper tension.
I've had it happen on occasion and in that twilight state between awake and asleep I felt as if I were falling only to be startled out of sleep by that flinch as the muscles tense up.
I hope it doesn't disturb your night's rest.
2007-08-27 14:00:19 · answer #2 · answered by Albannach 6 · 0⤊ 0⤋
I don't know what it's called, but the cause is your muscles relaxing. You body is totally calm and relaxed right before you fall asleep. Your muscles need that break too, so it's kinda like they are releasing the last tensions of the day to fall asleep with you :o)
2007-08-27 13:54:20 · answer #3 · answered by laura_paura 5 · 0⤊ 0⤋
Mine varies from a mild jolt to almost a white flash and explosion. The falling one and waking up with a jolt is common. Some people think it's a defense mechanism from when our ancestors slept in trees and were worried about falling out.
2016-05-19 21:30:26 · answer #4 · answered by ? 3 · 0⤊ 0⤋
Interesting question!
"Hypnic jerks" is the term you're looking for I believe.
2007-08-27 14:29:47 · answer #5 · answered by Army Nurse 2 · 0⤊ 0⤋
is your spasms in your calves??? usually calf cramping at night is cause by a potassium deficiency....therefore eat a banana
2007-08-27 13:53:19 · answer #6 · answered by Taryn M 1 · 0⤊ 1⤋
Well I guess someone did take the "Goodnight, don't let the bed bugs bite" too serious.
2007-08-27 14:14:09 · answer #7 · answered by Anonymous · 0⤊ 0⤋