IUBio

an uninformed question...

John H. John at faraway.com.au
Fri Sep 21 04:12:45 EST 2001


The thalamic theme received prominence in the mid 80's, Crick and Koch I
believe. Francis Crick of DNA fame that is (incidentally, saw an interview
with Perutz recently - he received Nobel for Haemoglobin structure - who
said that Crick worked with him and made a very big contribution. Then Crick
turned to Neuroscience and we all should be very grateful for that. Anyway,
he and Koch came up with something like the Thalamic searchlight hypothesis.
Haven't read it and and I don't give it an intellectual hoot about
consciousness per se, let alone human consciousness. I do not think
consciousness is rooted in some gross anatomical structure(no, I'm not a
dualist and still entertain and proto cortico thalamic loop scenario as this
structure goes deep into evolutionary time). Human selves probably require
our specific neuro-anatopmy, but not consciousness, and there I go with
those f****** semantics again. I think the poet Eliot best surmises our
endeavours in this regard:

East Coker

So here I am, in the middle way, having had twenty years -
Twenty years largely wasted, the years of l'entre deux guerres -
Trying to learn to use words, and every attempt
Is a wholly new start, and a different kind of failure
Because one has only learnt ot the get the better of words
For the thing one no longer has to say, or the way in which
One is no longer disposed to say it. And so each venture
Is a new beginning, a raid on the inarticulate
With shabby equipment always deteriorating
In the general mess of imprecision of feeling,
Undisciplined squads of emotion And what there is to
 conquer
By strength and submission, has already been discovered.

....

Home is where one starts from. As we grow older
The world becomes stranger, the pattern more complicated
Of dead and living. Not the intense moment
Isolated, with no before and after,
But a lifetime burning in every moment
And not the lifetime of one man only
But of old stones that cannot be deciphered.

At this point in time I'm quite happy to leave consciousness to the poets.
Edelman's reentrant ideas strike me as the brightest and best, and then I
have read somewhere that his ideas were originally put forward a long time
by an Italian (?) neuroscientist in the late 60's I think. That is not to
say Edelman plagiarised or stole, for quoting Eliot again: the immature poet
imitates, the mature poet plagiarises. Edelman has immeasurably expanded the
work, and invokes a powerful evolutionary emphasis that is one of my
particular biases. I don't think we should be worrying too much about human
consciousness at present, I'm still trying to come to terms with the idea of
kangaroos, possibly even crows,  being conscious.

John H.




TFunk wrote in message <9o3l0p$24kr$1 at bigboote.WPI.EDU>...
>It has seemed to me for some time now that human consciousness is directed
>by a system of neural relays over which we may learn to associate
particular
>types of activity at one location in the brain with relevant corresponding
>activity in another location. For example, at an early age, we learn to
>associate a particular sensory input with the color red, and as we progress
>into more complicated reasoning skills this knowledge is an elemental
>association between a portion of the optical cortex and a corresponding
>portion of Wernicke's area (if I recall correctly that this is the language
>center). A person sufficiently educated in the color red and some other
>social conventions of association learns to relay the visual
acknowledgement
>of a red octogon with a particular sequence of motor controls, which in the
>proper context has the ultimate effect of decelerating a car. I'm sure many
>have observed a tendency to have this habitual motor reaction even at times
>in which they aren't in the driver's seat, simply because the neurological
>reaction is embedded without sufficient discriminatory criteria.
>But on to the question. I've read that the Thalamus is a region in the
brain
>which has reaction to stimuli at any of the human sensory structures. Is it

>possibly or probably true that it is the responsibility of the Thalamus to
>govern the relaying of stimulus from one neural region to another?
>
>





More information about the Neur-sci mailing list

Send comments to us at biosci-help [At] net.bio.net