🚀 go-pugleaf

In article <BzF4sA.Jyx@dcs.glasgow.ac.uk> ,
jack@dcs.glasgow.ac.uk (Jack Campin) writes:

>geb@cs.pitt.edu (Gordon Banks) wrote: 
>> RGINZBERG@eagle.wesleyan.edu (Ruth Ginzberg) writes: 
>>> Does anyone know what causes the sensation (when just falling asleep) 
>>> of sudden literal falling, followed by a startle reaction that wakes 
>>> you right up? 

>what the heck is it FOR?  Anything this widespread ought to have some 
>physiological function and evolutionary rationale, surely? 

I think it's associated with the disconnection of gravity sensors in the
sleep state.

This is offered from a strictly subjective point of view, and may not have
any neuro-biological basis, but when I'm asleep I tend to maintain a
certain amount of body awareness.  For example, if I'm sleeping on my side
with one knee cocked, I am more likely to have dreams about climbing stairs
or some similar activity requiring the same body position.

But even though I have a limited amount of body awareness, I have no sense
of gravity tugging on my body.  I have a sense of "down" in the direction
of my feet (which places the dream ground at a 90 degree angle to waking
ground, since I dream I'm vertical when in fact I'm horizontal), but in my
dreams I don't feel the pressure of the earth against my feet, or the
effort of holding myself erect.

I suspect this gravity disconnect is necessary for dreaming about activity,
otherwise we'd probably only have dreams of lying down.

As to the occasional falling sensation when falling asleep, perhaps
sometimes the gravity disconnect occurs before we're fully asleep.  On
these occasions perhaps we feel the absence of gravity before we've
completely abandoned our gravitational responsibilities.

--
Ken Easlon                | "...somebody spoke and I went into a dream..."
ken@holonet.net           |    -Paul McCartney
Pleasantly Unaffiliated   |