Re: Molecules and Neurons - and photons


"feedbackdroid" <feedbackdroid@xxxxxxxxx> wrote in message
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Alpha wrote:
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Alpha wrote:
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zzbunker@xxxxxxxxxxxx wrote:


the only
thing philosophers know about vision,
dinosaurs knew 100,000,000 years aqo.




Whatdayathink, ZZ? My contention is that dogs, for instance, "see"
the
outside world in very much the same way that humans see it. They
open
their eyes, and wham!!!

They see something such that the best philosophical "metaphor"
[notice
I said metaphor here] is of the little doggy-homunculus viewing the
internal Cartesian Theater screen. Which is obviously impossible,
but
happens to be the best metaphor the philosophers have provided us,
yet,
for how vision works.

Jeff Hawkins in On Intelligence, claiming that the cortex is a
memory-prediction machine (a very interesting hypothesis backed by a
lot
of
info Hawkins provides in the book), also posits that when we sense
something, brain/cortex starts its filling in process immediately,
completing tunes, visual scenes etc., on the basis of incomplete data
or
no
data at all (when predicting what will come next - the next note in a
tune
etc.). The memory is a storage of patterns of prior activation
potentials
as they coursed through the cortex. All parts of cortex do essentailly
the
same thing (the cortical algorithm) when representing (hierachically)
prior
experience that is then recalled in an auto-associative manner *as*
new
stimuli are encountered. When a difference is noticed (between the
recalled/already-present patterns of APs and the new pattern of APs
presented as a recept/percept), attention is brought to bear on the
difference and we notice it immediately (like a melody with a note
difference from the way we heard it before). He has lots of examples
of
this way of functioning in the book. A clear and engaging read.

To the point made by feedbackdroid vis theater-homunculi, it seems
that
the
theater can be thought of as the recall of prior experience patterns
and
the
homunculus is the attentional function. After all, we can and do
recall
past
experiences and seem to visualize those scenarios etc. in our "mind's
eye".




In short, "mental imagery" is a fact. The problem regards how it
actually works.

A couple more observations from the book: memory of patterns is stored as
invariant representations, in hierarchies (using LTM-like processes).
Feedback down the various hierarchies is the predicted pattern which is
compared with the ascending/forward-feeding stimulus signal. I am about
half-way through the book and the remainder is more about the hows. So I
will update when done.




I've read Hawkin's' book a couple of times. Everything is fine ....
however ... this still doesn't quite explain the illusion [whatever]
analogous to the homunculus-cartesiantheater problem. Why do we
actually "see" the way we do. Sticking Hawkins model into a computer -
which is eminently doable - doesn't seem to solve the problem. there is
something missing.

Are you referring to the experience of seeing - the quale/qualia issue?






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