I am interested in knowing what kind of research setting you are involved
in.
Thanks,
Barb Smith
----------
> De : John St. Julien <stjulien who-is-at UDel.Edu>
> A : xmca who-is-at weber.ucsd.edu
> Objet : Re: a request (with a bit more)
> Date : dimanche 15 mars 1998 02:06
>
> Judy (and xmcaites),
>
> Though I am not sure, I suspect that your student has run across
references
> to "Parallel Distributed Processing" possibly through references to a
> semi-famous debate in cog science journals centered on modeling the
> acquisition of the english past tense.
>
> There is a fair amount to be untangled here: Parallel Distributed
> Processing has become a term applied only to one school: centered around
> Rumelhart and McClelland and the former PDP group originally at UC San
> Diego. (I've always wondered about this.) Connectionism has become the
> favored academic term and that is the way that the most recent references
> will be indexed. It should be distinguished from "Neural Networks" which
is
> a highly technical, and technologized offshoot which is unlikely to be
> helpful.
>
> Literacy acquisition is not my field, and my interest in these ideas are
> through my focus on trying to understand just what it is that changes
when
> we say something has been learned-and how that necessarily material
process
> constrains theories of learning and instruction. So if I say the obvious
> just let me know.
>
> The seminal reference in the past tense debate is: McClelland, James L.
and
> David E. Rumelhart. "On Learning the Past Tenses of English Verbs." In
> Parallel Distributed Processing, Volume 2: Psychological and Biological
> Models, eds. David E. Rumelhart, James L. McClelland, and the PDP
Research
> Group, 216-271. Cambridge: MIT Press, 1986. It is in part a reaction to
an
> earlier Pinker book which relies on hidden explicit rules. A variant is
> supposed to have appeared in MacWhinney's "Mechanisms of Language
> Acquisition."
>
> A reference that discusses the debate and should help open out to other
> sources and lines of research is: Bechtel, William and Adele Abrahamsen.
> Connectionism and the Mind. Cambridge, MA: Blackwell, 1991.
>
> Hope this helps, and touches on what your student is interested in.
>
> ____Some laignappe--something a bit extra.
> There is an interesting bit of history here: Rumelhart is generally
> acknowledged as the formulator of the most recent version of the
> influential concept of "schemata." Rumelhart's work was then focused on
how
> children learn to read for meaning and more specifically to understand
how
> it is possible to "make up" and extend stories in various genres--an
> ability that he felt had to be tied to children's ability to read a text
> creatively and to insert their own meanings. (I suspect he might have
been
> more cautious in his characterization but that is the way I read the
> direction.) From this, pulling on Chomsky's generative grammar, and the
> emerging formalism of Artificial Intelligence he developed a
structuralist
> concept of schemata as an acquired data structure 'filled' with differing
> specifics from experience. You'll still see many pro forma references to
> his 77 or 80 work in the educational literature using this concept.
(Though
> he always felt that his intuition about schemata was never matched by the
> models because the representations he was using were not active enough.)
>
> His radical revision of this idea and the reason for it has received very
> little play in educational or other practice-oriented fields. In
> Rumelhart's view the problems with his early attempts to instantiate the
> concept lay in the inflexibility of the data structures; it was hard to
see
> how anything approaching the flexibility of human learning could result.
> For Rumelhart and his colleagues the solution lay in abandoning the idea
of
> data structures, their problematic storage and retrieval, and dubious
> filling of default assignments altogether. Inspired by the massively
> parallel and distributed nature of the architecture of the brain they
> postulated a massively interconnected system linked to the world in such
a
> deep way that representations were better thought of evoked by
experience,
> with each evocation being an unique response to the situation based on
> prior experience. With the caveat that we can provide ourselves with
> evocative models and replays of experience, the notion is that the entire
> system is based on constraint satisfaction, it reorganizes in significant
> ways in response to each experience and that we don't retrieve memories
but
> recreate them in terms of the immediate problematic situation. This gave
> Rumelhart the dynamic, active schemata he wanted but at the cost of what
> most folks would understand as representation. The fundamental operation
is
> pattern completion, not formal logic over basically static
representations.
>
> _____and some ruminations:
> When I ran across connectionist ideas it seemed to me that they were
almost
> tailor-made to fit into the framework put forward by the pragmatists and
I
> still think so. But the pragmatist vision was much broader and included a
> strong sense of the role of activity and "ends in view" (goals) than
> connectionists have put forward. (I have come to understand those
operating
> out of Vygotskian or several other practice-oriented traditions might
make
> the same objection.) In the first chapter of the book cited above
Rumelhart
> et al. introduce issues of external representation, formal logic and goal
> seeking and do a credible job of laying out a program to research these
> from within a connectionist perspective. To my knowledge the issue of
> formal logic has been rather handily dealt with but the other two crucial
> elements, goals and external representation, have languished. This,
> especially external representation seems ideal for situated perspectives
to
> comment on. Pragmatism certainly had a finely graded series of "ends in
> view" to add to the tool box. -----But few working in practice oriented
> traditions seem interested in the material basis of learning within folks
> (as opposed to communities) and the ways that it might powerfully
constrain
> the way we theorize. The political, policy and cultural implications are
> very large--facts vanish in the connectionist story and the structure of
> testing that organizes schooling will make little "scientific sense" if
> this view prevails (and it is my judgement that it will prevail.) Nate a
> bit back introduced some suggestive material and got no response.
>
> My Question: Why isn't the material basis for learning (in-the-head
> learning) interesting?
>
> Thanks for your patience, John
>
>
>
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> John St. Julien (stjulien who-is-at udel.edu)
> Department of Educational Development
> University of Delaware
>