Spasms & Drowsiness

[DaFunkyUnit]

When you're about to doze off, yet trying to stay awake (ie. like in lectures at school, or meetings at work) why do you have spasms (like the head nodding off, then yanking back up) ?

[DarkFury]

Yup... that's natural. Snnnnnzzzzz <YANK>

[bachviet]

'Cauze you are half consious about it.

[nickel]

Hi Alice,

How come when you just start to fall asleep, you get a jolt in the leg or arms? What is this called and what causes it?



Dear Reader,

That's called a hypnic jerk, and these jerks are a normal part of the body's transition from being awake and alert to going to sleep. Unfortunately, the scientific world is not united on what exactly causes it, but there are two hypotheses. The first is that the jerking motion is part and parcel of the physical changes that accompany going to sleep — your breathing slows down, your temperature drops, and your muscle tone changes.

The second hypothesis is that your brain interprets all of the signs of relaxation as a sign that you're falling and then shoots out a message to jerk your limbs to stay upright. This may seem more plausible to some people, since many experience a sensation or visions of falling as they drift into sleep. In fact, this might also be why you see some people jerking awake in the library after falling asleep over their textbooks.

Most people have hypnic jerks at some point, but many won't recognize them since they aren't strong enough to wake them up. There is something wrong, however, if you have Periodic Limb Movement, what used to be known as myoclonic jerking. In this case, you don't just have one light jerk, but a series of jerks at precise time intervals that can go on for hours. Amazingly, many people who have myoclonic jerking may not realize it. If you share a bed, however, your bed partner won't be able to ignore the signs. If you think you might have Periodic Limb Movement, and it's a problem for you and/or others, then your health care provider can evaluate you to identify a cause and find out what you can do about managing the condition.

In all probability, however, you are experiencing a normal hypnic jerk: nothing to be concerned about — it's annoying, as most jerks tend to be.

Alice

[DaFunkyUnit]

hypnic jerk huh?

well i was just at the jerk store the other day. and they were all out of YOU!

[ShawnLee]

hypnic jerk huh?

well i was just at the jerk store the other day. and they were all out of YOU!

Oooohhhhh!

[ialsohaveadream]

It's called a hypnic, jerk. (See what a little punctuation change can do for your sentences?)

[kei2]

I have a third hypothesis: that you are semi-consciously realizing that you either are falling asleep or have fallen asleep, and that this revelation causes you to snap awake, sometimes violently. I mean, if I'm just taking a nap I don't get the whole "hypnic jerk" thing upon waking up... but if I fall asleep in class I do. I suspect this is because I know I shouldn't be asleep in class and am subconsciously worried that I am missing lecture material or something.

[RoniMan]

just remember, make sure that when you have your hypnic jerk, you're not next to a concrete wall.

i was in chem class one day, and fell asleep. the hypnic jerk introduced my head to the wall....and it hurt like a BICH!

[ShawnLee]

just remember, make sure that when you have your hypnic jerk, you're not next to a concrete wall.

i was in chem class one day, and fell asleep. the hypnic jerk introduced my head to the wall....and it hurt like a BICH!

DUDE! I've done that many times. The worst ever for me was in junior high. In eighth grade, at the frog dissection lab, I fell asleep with my pencil in my hand and jerked it into my other hand and had a piece of 0.5mm lead stuck into my palm. I didn't even think about it at first but Mr. Binkley later said, "It's a good thing you weren't the one with the scalpel."

[avlena]

Most people have hypnic jerks at some point, but many won't recognize them since they aren't strong enough to wake them up. There is something wrong, however, if you have Periodic Limb Movement, what used to be known as myoclonic jerking. In this case, you don't just have one light jerk, but a series of jerks at precise time intervals that can go on for hours. Amazingly, many people who have myoclonic jerking may not realize it. If you share a bed, however, your bed partner won't be able to ignore the signs. If you think you might have Periodic Limb Movement, and it's a problem for you and/or others, then your health care provider can evaluate you to identify a cause and find out what you can do about managing the condition.

In all probability, however, you are experiencing a normal hypnic jerk: nothing to be concerned about — it's annoying, as most jerks tend to be.

Alice

My fiance does this... it's kinda cute. i know he's falling asleep when every part of his body twitches, one after the other... first his leg... then the other... then his arm... etc. after most of his body parts have twitched in some way or other, it stops, and he's completely out of it. although, it can get a bit hazardous, cuz he's accidentally kicked me before!