Few long-standing questions about neocortex for the attention

F. Frank LeFever flefever at ix.netcom.com
Tue Mar 10 22:21:03 EST 1998


In <3.0.32.19980306212705.0069298c at pobox2.stanford.edu>
kharazia at POBOX2.STANFORD.EDU (Viktor Kharazia) writes: 
>
>a. What is the function of the neocortex? Why it is so prominent in
higher
>mammals?
>b. Is there a foundation of the human intelligence in the neocortex?
If it
>is, where it might be?
>c. Is the anything really unique about cerebral cortex, structurally
or
>chemically? Something, that can't be found anywhere else.
> 
>I know, there are not going to be any answers but... 
>VK
>
The most obvious answer you might get is to begin by reading some
introductory texts in  (e.g.) physiological psychology, comparative
anatomy, etc. and then reframe your questions.

I will give you a quirky, deceptively simple answer, which might
however shape your approach to these questions.

(I believe I am cribbing from C. Judson Herrick, whose work I read
long, long ago...)

In the beginning, in very primitive ancestral organisms, a sensory cell
communicated directly to a motor cell, so that a stimulus (e.g. a
touch) produced a response (e.g. movement away).

Later organisms involved more than one sensor or more than one motor
element, and even later ones had some kind of conditional response
based on their interactions (e.g. move away from touch if gut sensor
reads "full" but not if it reads "empty").

The thalamus is a subcortical structure developed much much later which
(among other things it does) relays several different kinds of sensory
information: touch, sound, visual, taste.

Relays it to WHAT?

Well, note that left out "smell" in the list above...

It can be argued that all the other sensory inputs long ago were
reported to the "smell" cell cells.

People nowadays have heard of the "rhinencephalon" or "smell brain" as
a PART of the brain (including primitive cortex) involved with
"emotion" etc.; but it can be argued that the ENTIRE cortex developed
with the "smell cells" as its core.



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