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From: gerryg@il.us.swissbank.com (Gerald Gleason)
Subject: Re: What's innate? (Was Re: Artificial Neural Networks and Cognition
Message-ID: <1995Jan25.164422.17976@il.us.swissbank.com>
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Date: Wed, 25 Jan 1995 16:44:22 GMT
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Mark Rosenfelder writes
> In article <3g169u$s8o@mp.cs.niu.edu>, Neil Rickert <rickert@cs.niu.edu>  
wrote:

> >Our adaptation for language required some changes in throat
> >structure, and motor neurons for the musculature of the vocal chord.
> >It most likely required new higher level structures in the brain.
> >But the new musculature and neural tissue could be very similar to
> >existing such structures dealing with other parts of the anatomy.  If
> >that were the case, these might result from relatively simple changes
> >to the genotype.  But if the language specific neural tissue is a
> >near copy of other neural tissue, then language learning must uses
> >processes similar to those used for learning in other domains.  That
> >is, language acquisition must be part of a general learning facility.

> The last sentence doesn't follow.  We don't know that there *is* a
> "general learning facility"; there might be a number of specialized
> learning systems.  And it could be that a language facility developed
> out of some existing *specialized* subsystem (one dealing with primate
> calls, for instance).

No, it does follow.  Neil is saying that that since it is neural tissues  
that are doing any learning that goes on, that there is a 'the way neural  
tissue learns' that can be discovered in principle.  Otherwise you must be  
able to say that the neural tissue in the language specific areas is  
anatomically different.

On the other hand, there is a lot of real specialization in the brain, and  
we know that it has a layered structure of successively more primitive  
sub-systems.  The way learning works could have fundamental differences  
for functions localized in a particular layer.  If I understand the  
anatomy corectly, most of the language specific areas that have been  
identified are in the neo-cortex.  This is the layer that must have the  
most general and adaptive learning mechanisms based on everything we know  
about brain structure.  The facts about lateralization of function within  
the brain (in other words, the left-brain, right-brain stuff) is likely to  
be relavent to this debate.


> The poverty of stimulus argument is not the only basis for UG.  Other
> important grounds include

> a. Children seem to avoid whole classes of mistakes; one would rather
> expect to find more *kinds* of mistakes if they started out with no clue
> as to the structure of language

Clearly there is the possibility of genetically imprinting instincts.   
There are many stimuli that we are pre-programmed to respond to in  
particular ways.  Also, there would be functional limitations that would  
be related to the capabilities of the general learning capacity, and these  
features would be visable in terms of permitted language structures.

> b. Language (unlike say cooking or hunting) has been linked to
> particular areas of the brain

Although this is relavent in the way I stated above, there is also strong  
evidence that if the language areas are destroyed early in development,  
the functions can move to undamaged areas.  This plasticity of brain  
structure is the best evidence in favor of the general learning ability  
arguments.

> c. All natural languages share some grammatical properties; a fact
> easily explained with UG, but requiring some other explanation without
> it.

I have suggested a number of possibilities for the source of language  
regularities.  There is also the fact that human language is imbedded in  
human life and society, so we have another plausable source for much
of the regularity.

Gerry Gleason
