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From: klas@dick.imb.uh.edu (Klas Hedenstierna)
Newsgroups: sci.bio
Subject: <None>
Message-ID: <1991Feb27.080147.13467@menudo.uh.edu>
Date: 27 Feb 91 08:01:47 GMT
References: <1991Feb26.143844.12561@lonex.radc.af.mil>
Sender: usenet@menudo.uh.edu (USENET News System)
Reply-To: klas@dick.imb.uh.edu (Klas Hedenstierna)
Organization: University of Houston, Department of Biochemical
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and Biophysical Sciences
Subject: Re: Twitching/Pimples
Keywords: Twitching


In article <515@spam.ua.oz>, jcoleman@spam.ua.oz (James L Coleman) writes:
|> Does anybody know why people twitch as they are falling asleep?

In article <1991Feb26.143844.12561@lonex.radc.af.mil>,
vanderwerkend@lonex.radc.af.mil (Dan Vanderwerken) writes:
|> I often find that the medical community doesn't have solid answers
|> for questions
|> like these...maybe because twitching doesn't cause serious
|> harm/death, and
|> if it's not that serious why worry about it?  I've twitched and
|> jumped a
|> few times in the past just prior to falling asleep and this is what
|> I've
|> noticed:
|> 
|> *  I usually twitch in response to a dream.  For example, my most
|> violent
|> jumps have been a response to a dream that I've fallen down (just as
|> I'm
|> drifting off to sleep).

I have heard this phenomenon described, but I can't remember where or what it
is called. It is, as Dan Vanderwerken notes, usually associated with a
feeling of
falling. I experience it myself a few times per month. I remember that
my source
speculated that it could have something to do with the fact that at some
time
during our evolutionary history we used to sleep in trees just as
chimpanzees
and, I believe, many other Primates do. Our present day twitch could
then perhaps
be a remnant of some ancient reflex that allowed our ancestors to
quickly wake
up and prevent a fall.

Klas Hedenstierna
University of Houston
Department of Biochemical and Biohysical Sciences
klas@dick.imb.uh.edu