>Subject: visual detail
>From: daan daanBACHvdb at wins.uva.nl>Date: Sun, 07 November 1999 06:28 PM EST
>Message-id: <38260B37.C0491951 at wins.uva.nl>
>>I found out about visual perception, that the further we go into the
>brain (following afferent pathway) larger cells (complex and
>hypercomplex) keep track of constantly increasing abstraction. First of
>lines, then of shapes etc. So this is a way macroscopic features can be
>extracted from a visual scene.
>>Now my question is - because I cannot find anything about it - does
>anyone know wether something like that also exists for detail (ie
>microscopic features)? In other words: how is detail preserved in the
>afferent visual pathway?
on this, the future might prove me wrong, but, when the details exist in the
environment, why store them internally? why not store only information
sufficient for 'recognizing' the details when they are experienced, or to
recreate them via successive approximations, as Artists do, with one brush
stroke prompting the next? (why artists continually refer to their subjects in
the 'image' is in the light... in the EM. why recreate it, and store the
recreation, in the brain?
in this way, storing abstract TD E/I-minimizations, which allow 'recognitions',
not only takes care of everything, but also eliminates the
completely-unnecessary step of 'translating' from an internal 'visual image'
during 'normal' processing.
in this view, the 'TV screen' is the retina.
this view can be tested experimentally by recording from the retina, for
instance, during REM-Sleep. if the view is correct, there will be retinal
activation even in the absence of light, and which is the 'TV screen' for
i'm inclined this way, although i've not searched for such in the literature,
from close observation of my own experience. i routinely think in pictures... i
can be 'watching' TV, not seeing the TV, but, rather, the 'thought' that i'm
'thinking'... the more-demanding the thought, the more the external environment
'disappears'... i'm sitting there, eyes on the TV, but, afterward, realize that
i 'missed the show', or a portion of it, even though i was 'looking' at the TV.
it's the same with respect to audition; 'listening' to a lecture, only to
realize a bit later that i was 'elsewhere', and didn't even hear the protion of
the talk... but i can recall the imagery of the problem i was working on.
i'm sure it's a matter of selective 'attention' because, when a stimulus
arrives from the TV, like those obnoxiously-realistic telephone rings that the
advertising folks deliberately stick into their commercials, my internal image
'goes away', if only briefly, and i see the TV image.
the environmental EM is so rich. we routinely 'see' the same stuff, without
consciously Seeing it, until we learn a bit, then, and only then, do we See it.
there's internal 'feedback' that's necessary, and i might be wrong, but i've
come to see it as happening in the retina, where the full richness of the
environmental EM bathes the nervous system in its wealth of information... and
the nervous system takes what it recognizes and 'disregards' the rest... learn
more, recognize more, See more. Science does such as a matter of course. So do
Religion and Philosophy, come to think of it, only Religion and Philosophy do
more of the inside-out Seeing than does Science... Interesting insight.
don't ask me to 'volunteer'. the thought of electrodes in my retinas doesn't
attract me :-)
there's an article in the Nov. 99 _Scientific American_, "Vision: A window on
Consciousness", by N. K. Logothetis, p68. Gusee i'll have to take the 'time' to
read it now that i've "gone off half cocked" :-)
i'll comment further, after reading the article, if it's necessary.
cheers, ken collins