From: Lee Corbin (lcorbin@tsoft.com)
Date: Wed Feb 12 2003 - 17:38:48 MST
Brent writes... (by the way, welcome back to the list, Brent!)
> Lee said:
>
> >>>Suppose I wonder whether there is such a
> representation of my monitor---on which
> I'm reading email---in my brain. It turns
> out that there is. In our visual cortex
> (I forget whether it's V4 or what), there
> indeed is such a literal mapping<<<
>
> Yes, you’ve got it! There is an actual scale model in our head!
No, I guess that the closest I'm coming so far to your
position is a 2D picture of the 3D object. You believe
that there is a little 3D model of the external object
somewhere in the brain. Right?
> And the monitor that you are consciously aware of, that you only think is the
> real thing in front of your real head is really simply this "mapping" in your
> brain.
Well, sorry to pick a nit: but to be clear, when I refer
to "my monitor" I am not referring to what's in my brain.
I am referring to the glass and plastic item eight inches
from my brain.
> Everything you are consciously aware of is simply information
> in your brain that represents the reality beyond our senses –
> not reality itself.
Well, again, the words can mean either thing. It's a
little bit like the puzzler "do we see airplanes, or
do we see the photons reflected off the airplanes?"
I like to say that we see the airplanes, but I know
what people mean when they say that we see photons.
You are totally correct, of course, that the information
must be represented in my brain somehow. It would be
VERY hard to find anyone on this list who'd disagree
with that. Therefore, the point does not need to be
stressed IMO. What you need to stress---and you do---
is that there is some kind of true-to-life model in
the brain, whereas I think that most people on this
list believe that the representation of objects in
the brain is much more subtle, the encoding much, much
more obscure. For example, the pattern might even have
a dimension in time (I don't know that it doesn't), so
that when I visualize a cube it's like my brain is a
computer rapidly executing thousands of instructions
the way that a scanning beam on a TV does.
> The important thing is these conscious representations are more real than
> reality itself. We know such exists more than we know reality itself exists.
This is true, because, as materialists have realized for
centuries, my brain might be in a vat in Moscow for all
I know. As to what is more "real", my mental representation
or the physical plastic and glass in front of me, well, that
depends on how "real" is taken. As a devout materialist and
realist, I consider the real monitor in front of me to be
certainly no less real than any representation I may have of
it.
> They are made of qualia or the phenomenal properties of something in our brain –
> something traditional cause and effect science alone is unable to observe. In
> order to discover and observe what/how these phenomenal qualities are requires
> effing. (see my paper at http://home.attbi.com/~brent.allsop)
Yes. I studied your paper last year. I should look at it again
because I know that you were in the process of improving it.
> >>>Monkeys eyes were held fixed while they
> > steadily looked at a certain geometric
> > figure (a grid or a triangle, I forget).
> > Then they were instantly killed, and it
> > was found that this same grid was
> > present, and spatially too, in their
> > visual cortex (at the back of their heads).
> > So it seems that we do have a picture in
> > our heads for visual information.<<<
>
> This is new to me and frankly hard to believe.
> The representations survive past death?
Oh yes. But this is a 2D representation, so don't
get too excited. The scientists took a cross
section of some part of the visual cortex, and
when they stained that thin slice in the right
way, they got the picture of what the monkey
was looking at.
> Do you have some references or something?
Sorry, no. I read this perhaps 15 years ago in
some book. But I remember quite clearly that
this is how it is. Now, since we would hardly
be surprised to learn of a retinal image of
the geometric object, why should we be surprised
that this is relayed to the visual cortex in a
way that preserves its 2D features?
Lee
This archive was generated by hypermail 2.1.5 : Wed Feb 12 2003 - 20:59:39 MST