Axon collaterals ?

k p Collins kpaulc at [----------]earthlink.net
Fri Jan 2 13:52:00 EST 2004


Hi Matthew.

"Matthew Kirkcaldie" <Matthew.Kirkcaldie at removethis.newcastle.edu.au> wrote
in message
news:Matthew.Kirkcaldie-8AD1A5.12334702012004 at seagoon.newcastle.edu.au...
> [...]

Thank you for your Cogent discussion, and please Forgive me
when I 'challenge' you with respect to the following:

> And yet it's the simplest interaction in the brain.  Multiply it by
> itself around 10 000 or 100 000 times, keeping in mind that it
> continuously shifts its connectional structure, and you start to
> understand why I have no time for people who feel they can understand
> behaviour at the receptor level, or describe cortical "function" in
> anything but the wildest of guesses.
> [...]

Just as is the case with respect to written communications,
it's a matter of degree-of-neuroanatomical-context
that is maintained.

.

Typing a "period", as in the 'sentence' immediately-above
doesn't convey much information.

But placing a neuron in its overal global-neuroanatomical
"context" enables one to pin its functionality down in a way
that's commensurate with the degree to which that overall
"context" is, in fact, carried through.

One might think that, if there's so much complexity that
has to be dealt with with respect to a =single= neuron's
functioning, then how can there be any hope for understand-
ing the massed functioning of many such neurons, within the
massed functioning of many other types of neurons, but
there's not only hope, it's flat-out doable - because there
exists an overall order that delimits what can be going on
within the nervous system [within the brain], and which
can be followed to any 'level' of such delimitation.

The problem is just big, not 'impossible'.

For instance, for a behavior to be manifested, the effectors
must be driven.

It's easy to see, in such, the "delimitation' of pyramidal cell
functioning that's allowed.

So, then, 'go' to the pyramidal cells, and using the "delimita-
tion" from the preceding 'step', extend it to the neurons that
are in communication with the pyramidal cells.

And so forth.

At every 'step' the "delimitation" not only carries forward,
but augments.

So one doesn't have to address all the permutations of
any neurons functionality. One only has to address this
increasingly-delimited set of all possible permutations.

And, given the overall neuroanatomical context [for those
who have it, "the special topological homeomorphism of
central nervous systems", AoK, "Short Paper", explicitly,
and the rest of AoK in general], the 'chain of delimitation'
is plainly readable.

In my view, the 'problem' has been that folks 'forget' about
the global Neuroanatomy, and all of the constraints disclosed
within it, when they get up-close-and-personal with individual
neurons.

Doing so is like trying to figure out what the period-'sentence',
above, 'says'.

It doesn't 'say' anything, and it's good to understand why it
doesn't 'say' anything.

It doesn't 'say' anything because it exists outside of any
delimiting context.

Neronal function, same-old, same-old.

ken [k. p. collins]








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