This has been happening to me for a long time. I'll be falling asleep and almost in a dreamlike state, but not really dreaming and I have the feeling like I'm falling at a million miles an hour. And it's not just a dream, it feels real, my stomach will drop and everything. And then it kicks me right back awake. Sometimes it'll be sort of like a dream and I'll have the image that I'm falling off my bed or down a flight of steps, but I won't be fully asleep. The most recent occurance of this happened a few days ago. I was in history class and was starting to doze off and this happened to me about six times, one hitting me so hard I almost fell out of my seat. Does this happen to anyone else here? And does anyone have any idea what causes it?

I get that sometimes...sometimes its just when I lie down and close my eyes.

To me the feeling hits my chest and stomach and makes my head spin.

Everyone has that sensation from time to time.

hypnogic jerk

Hypnic jerk
From Wikipedia, the free encyclopedia.
A hypnic or hypnagogic jerk is an involuntary muscle twitch (more generally known as myoclonus or a myoclonic twitch) which often occurs during the transition from wakefulness to sleep (see hypnagogia).

It is often described as an electric shock or falling sensation, and can cause movement of the body in bed. Hypnic jerks are completely normal, and are experienced by most people, especially when over-tired or sleeping uncomfortably.

The exact cause of the sudden jerks is not clear, but there are hypotheses:

That it is a naturally occurring part of the sleep process, as is slower breathing, and reduced body temperature.
That the feelings associated with relaxation before sleep are misinterpreted by the brain as falling or toppling over, and by reflex the body jerks out the limbs to stay upright.
That in the same way a body will often twitch as a person dies (as a reflex to attempt to keep the body functioning) it is thought the body might misinterpret falling asleep as a situation in which the body needs to be stimulated.
Hypnic jerks are usually felt just once or twice per night. More regular (and usually less dramatic) muscle twitches often occur during normal sleep (perhaps as much as one every thirty seconds). In extreme cases, this may be classified as a disorder called periodic limb movement. The person with the disorder will usually sleep through the events.

When a subject is deprived of sleep and is trying to fight sleep, hypnic jerks can occur more often. This normally happens after the subject has sucsessfully deprived themselves of sleep for longer than 24 hours. It is as if it is a way of making the body forcefully stay awake.

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