IUBio

Opions Please! Why Does This Happen??

Richard Vickery Richard.Vickery at unsw.edu.au
Wed Nov 4 18:24:30 EST 1998


Chris wrote:

Chris,
I don't know that anyone will explain these experiences to
your satisfaction.  Aspects of them are familiar to me and
admit non-mystical answers, so I will deal with those.

> I lay down and begin to sink into a deep relaxation.  It often takes up to
> 30-40 minutes till I am so relaxed I can hardly move a muscle.  I begin to
> focus my attention on the darkness I see beneath my eyelids.  Like most
> people, I do not see complete darkness.  rather, I see the usual mish-mash
> of strange colors (sort of like static snow).  Suddenly, if my concentration
> on the colors is deep enough and my relaxation is at its greatest, my eyes
> begin to "convulse"; flutter in a sense, very rapidly.

I occasionally experience some eye movement.  My take is
that the eyes are moving to their sleeping position
("rolling up in the head" - very obvious in my baby when she
is on the edge of sleep") but 

> As they shake wildly, I begin to see brilliant
> flashes of light - like jolts of electricity, and I actually feel as if
> there is an electrical current flowing through me.

The disks in the rods and cones of your eye are turned over
at a high rate.  Now I can not recall where I read this, so
take it with a grain of salt, but IIRC the breakinging-off
of the old disks happens en masse, often when you wake in
the morning.  This event might be what causes the flashes of
light.  


> Shortly after "entering" this electrical tunnel my entire body feels as is
> it is on pins and needles and a numbing sensations sets in.  Within seconds
> after this occurs I truly begin feeling as if I am rising out of my own
> body.

	This is probably the least mysterious part.  By lying very
still, you restrict blood flow to parts of your body (over
long periods can cause of bed sores as in hospital
patients).  This oxygen deprivation causes paraesthesias
(unusual feelings - ie pins and needles).
	Virtually all sensory neurons show "adaptation".  What this
means is that their response to a prolonged stimulus
declines.  This probably explains your weightlessness and
feeling of floating - I think that it also explains the
"falling" dream.  What happens is that the tactile receptors
on your back are stimulated by the pressure of you lying on
them.  After a while though, they adapt and cease to fire. 
In your case, your vestibular system tells you that you are
lying down, but your tactile system tells you nothing is
holding you up.  The only conclusion your brain can reach is
that you are floating.  (The same explanation holds for the
falling dream, but in this case, as you are not aware of the
start, the first assumption is falling not floating as
falling is a more common experience and also more
important).

Hope this helps

Richard Vickery



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