[comp.ai.neural-nets] Neuron Digest V7 #3

neuron-request@HPLMS2.HPL.HP.COM ("Neuron-Digest Moderator Peter Marvit") (01/11/91)

Neuron Digest   Thursday, 10 Jan 1991
                Volume 7 : Issue 3

Today's Topics:
        TR - Symbol Processing Systems, Connectionist Nets, etc.
        Preprint: Stimulus Sampling & Distributed Representations
               TR on the Modelling of Synaptic Plasticity
   4 vs 3 layers -- Tech Report available from connectionists archive
          Language, Tools and Brain: BBS Call for Commentators
                Consciousness: BBS Call for Commentators
       Full/Part-Time NN Research Assistant & Programmer Positions
POSTDOCTORAL POSITION IN NEW YORK AREA: Cognitive & NeuralModels of Human Learn
                   4th NN Conference. Indiana-Purdue.


Send submissions, questions, address maintenance and requests for old issues to
"neuron-request@hplabs.hp.com" or "{any backbone,uunet}!hplabs!neuron-request"
Use "ftp" to get old issues from hplpm.hpl.hp.com (15.255.176.205).

------------------------------------------------------------

Subject: TR - Symbol Processing Systems, Connectionist Nets, etc.
From:    honavar@iastate.edu
Date:    Tue, 18 Dec 90 15:08:02 -0600


The following technical report is available in postscript form
by anonymous ftp (courtesy Jordan Pollack of Ohio State Univ). 
Comments on the paper are welcome (please direct them to honavar@iastate.edu) 

_________________________________________________________________

Symbol Processing Systems, Connectionist Networks, and
Generalized Connectionist Networks

Vasant Honavar                          Leonard Uhr 
Department of Computer Science          Computer Sciences Department 
Iowa State University                   University of Wisconsin-Madison 

                Technical Report #90-24, December 1990
                Department of Computer Science
                Iowa State University, Ames, IA 50011 

                                Abstract

Many authors have suggested that SP (symbol processing) and CN
(connectionist network) models offer radically, or even fundamentally,
different paradigms for modeling intelligent behavior (see Schneider,
1987) and the design of intelligent systems. Others have argued that CN
models have little to contribute to our efforts to understand
intelligence (Fodor & Pylyshyn, 1988).

A critical examination of the popular characterizations of SP and CN
models suggests that neither of these extreme positions is justified.
There are many advantages to be gained by a synthesis of the best of both
SP and CN approaches in the design of intelligent systems.  The
Generalized connectionist networks (GCN) (alternately called generalized
neuromorphic systems (GNS)) introduced in this paper provide a framework
for such a synthesis.

______________________________________________________________________________

You will need a POSTSCRIPT printer to print the file. 
To obtain a copy of the report, use anonymous ftp from 
cheops.cis.ohio-state.edu (here is what the transaction looks like): 

% ftp
ftp> open cheops.cis.ohio-state.edu
Connected to cheops.cis.ohio-state.edu.
220 cheops.cis.ohio-state.edu FTP server (Version blah blah) ready.
Name (cheops.cis.ohio-state.edu:yourname): anonymous
331 Guest login ok, send ident as password.
Password: anything 
230 Guest login ok, access restrictions apply.
ftp> cd pub/neuroprose
250 CWD command successful.
ftp> bin  
200 Type set to I.
ftp> get honavar.symbolic.ps.Z 
200 PORT command successful.
150 Opening BINARY mode data connection for [[...]]
226 Transfer complete.
local: honavar.symbolic.ps.Z remote: honavar.symbolic.ps.Z
55121 bytes received in 1.8 seconds (30 Kbytes/s)
ftp> quit
221 Goodbye.
% uncompress honavar.symbolic.ps.Z
% lpr honavar.symbolic.ps 



------------------------------

Subject: Preprint: Stimulus Sampling & Distributed Representations
From:    gluck%psych@Forsythe.Stanford.EDU (Mark Gluck)
Date:    Wed, 19 Dec 90 07:29:57 -0800

PRE-PRINT AVAILABLE:

            Stimulus Sampling and Distributed Representations
                 in Adaptive Network Theories of Learning

                            Mark A. Gluck

                       Department of Psychology
                         Stanford University

      [To appear in: A. Healy, S. Kosslyn, & R. Shiffrin (Eds.),
        Festschrift for W. K. Estes. NJ: Erlbaum, 1991/in press]

                             ABSTRACT:

  Current adaptive network, or "connectionist", theories of human
learning are reminiscent of statistical learning theories of the 1950's
and early 1960's, the most influential of which was Stimulus Sampling
Theory, developed by W. K. Estes and colleagues (Estes, 1959; Atkinson &
Estes, 1963). This chapter reviews Stimulus Sampling Theory, noting some
of its strengths and weaknesses, and compares it to a recent network
model of human learning (Gluck & Bower, 1986, 1988a,b).  The network
model's LMS learning rule for updating associative weights represents a
significant advance over Stimulus Sampling Theory's more rudimentary
learning procedure.  In contrast, Stimulus Sampling Theory's stochastic
scheme for representing stimuli as distributed patterns of activity can
overcome some limitations of network theories which identify stimulus
cues with single active input nodes.  This leads us to consider a
distributed network model which embodies the processing assumptions of
our earlier network model but employs stimulus-representation assumptions
adopted from Stimulus Sampling Theory.  In this distributed network,
stimulus cues are represented by the stochastic activation of overlapping
populations of stimulus elements (input nodes).  Rather than replacing
the two previous learning theories, this distributed network combines the
best established concepts of the earlier theories and reduces to each of
them as special cases in those training situations where the previous
models have been most successful.

_________________________________________________________________

To request copies, send email to: gluck@psych.stanford.edu
 with your hard-copy mailing address.

Or mail to: Mark A. Gluck, Department of Psychology, Jordan Hall, Bldg. 420,
 Stanford Univ., Stanford, CA  94305-2130

------------------------------

Subject: TR on the Modelling of Synaptic Plasticity
From:    Patrick Thomas <thomasp@informatik.tu-muenchen.dbp.de>
Date:    27 Dec 90 13:27:38 +0100


The following technical report is now available:


                             BEYOND HEBB SYNAPSES:
             BIOLOGICAL BUILDING BLOCKS FOR UNSUPERVISED LEARNING
                         IN ARTIFICIAL NEURAL NETWORKS

                               Patrick V. Thomas

                               Report FKI-140-90

                                   Abstract

  This paper briefly reviews the neurobiology of synaptic plasticity as
  it is related to the formulation of learning rules for unsupervised
  learning in artificial neural networks. Presynaptic, postsynaptic and
  heterocellular mechanisms are discussed and their relevance to neural
  modelling is assessed. These include a variety of phenomena of
  potentiation as well as depression with time courses of action ranging
  from milliseconds to weeks. The original notion put forward by Donald
  Hebb stating that synaptic plasticity depends on correlated pre- and
  postsynaptic firing is reportedly inadequate. Although postsynaptic
  depolarization is necessary for associative changes in synaptic
  strength to take place (which conforms to the spirit of the hebbian
  law) the association is understood as being formed between pathways
  converging on the same postsynaptic neuron. The latter only serves as a
  supporting device carrying signals between activated dendritic regions
  and maintaining long-term changes through molecular mechanisms. It is
  further proposed to restrict the interactions of synaptic inputs to
  distinct compartments. The hebbian idea that the state of the
  postsynaptic neuron as a whole governs the sign and magnitude of
  changes at individual synapses is dropped in favor of local mechanisms
  which guide the depolarization-dependent associative learning process
  within dendritic compartments. Finally, a framework for the modelling
  of associative and non-associative mechanisms of synaptic plasticity at
  an intermediate level of abstraction, the Patchy Model Neuron, is
  sketched.


To obtain a copy of the technical report FKI-140-90 please send your physical
mail address to either "thomasp@lan.informatik.tu-muenchen.de" or Patrick V.
Thomas, Institute for Medical Psychology, Goethe-31, 8000 Munich 2, Germany.



------------------------------

Subject: 4 vs 3 layers -- Tech Report available from connectionists archive
From:    sontag@control.RUTGERS.EDU
Date:    Mon, 07 Jan 91 11:37:04 -0500


    REPORT AVAILABLE ON CAPABILITIES OF FOUR-LAYER vs THREE-LAYER NETS

At the request of a few people at NIPS, I placed in the connectionists
archive the postscript version of my report describing why TWO hidden
layers are sometimes necessary when solving function-approximation types
of problems, a fact that was mentioned in my poster.  (About 1/2 of the
report deals with the general question, while the other half is devoted
to the application to control that led me to this.)  Below are the
abstract and instructions on ftp retrieval.

I would very much welcome any discussion of the practical implications --
if any -- of the result.  If you want, send email to me and I can
summarize later for the net.

Happy palindromic year to all,
  -eduardo

 -----------------------------------------------------------------------------

Report SYCON-90-11, Rutgers Center for Systems and Control, October 1990

      FEEDBACK STABILIZATION USING TWO-HIDDEN-LAYER NETS

This report compares the representational capabilities of three-layer
(that is, "one hidden layer") and four-layer ("two hidden layer") nets
consisting of feedforward interconnections of linear threshold units.

It is remarked that for certain problems four layers are required,
contrary to what might be in principle expected from the known
approximation theorems.  The differences are not based on numerical
accuracy or number of units needed, nor on capabilities for feature
extraction, but rather on a much more basic classification into "direct"
and "inverse" problems.  The former correspond to the approximation of
continuous functions, while the latter are concerned with approximating
one-sided inverses of continuous functions ---and are often encountered
in the context of inverse kinematics determination or in control
questions.

A general result is given showing that nonlinear control systems can be
stabilized using four layers, but not in general using three layers.

 -----------------------------------------------------------------------

To obtain copies of the postscript file, please use Jordan Pollack's
service:

Example:
unix> ftp cheops.cis.ohio-state.edu          # (or ftp 128.146.8.62)
Name (cheops.cis.ohio-state.edu:): anonymous
Password (cheops.cis.ohio-state.edu:anonymous): <ret>
ftp> cd pub/neuroprose
ftp> binary
ftp> get
(remote-file) sontag.twolayer.ps
(local-file) twolayer.ps.Z
ftp> quit
unix> uncompress twolayer.ps
unix> lpr -P(your_local_postscript_printer) twolayer.ps

 ----------------------------------------------------------------------------
If you have any difficulties with the above, please send e-mail to
sontag@hilbert.rutgers.edu.  DO NOT "reply" to this message, please.


------------------------------

Subject: Language, Tools and Brain: BBS Call for Commentators
From:    Stevan Harnad <harnad@clarity.Princeton.EDU>
Date:    Thu, 20 Dec 90 22:55:40 -0500

Below is the abstract of a forthcoming target article to appear in
Behavioral and Brain Sciences (BBS), an international, interdisciplinary
journal that provides Open Peer Commentary on important and controversial
current research in the biobehavioral and cognitive sciences.
Commentators must be current BBS Associates or nominated by a current BBS
Associate. To be considered as a commentator on this article, to suggest
other appropriate commentators, or for information about how to become a
BBS Associate, please send email to:

harnad@clarity.princeton.edu  or harnad@pucc.bitnet        or write to:
BBS, 20 Nassau Street, #240, Princeton NJ 08542  [tel: 609-921-7771]

To help us put together a balanced list of commentators, please give some
indication of the aspects of the topic on which you would bring your
areas of expertise to bear if you are selected as a commentator.
____________________________________________________________________

      Language, Tools, and Brain:  The development and evolution of
                       hierarchically organized sequential behavior

                     Patricia Marks Greenfield
                     Department of Psychology 
                     University of California, UCLA
                     Los Angeles, CA 90024-1563
                electronic mail: rygreen@uclasscf.bitnet

Abstract: During the first two years of life a common neural substrate
(roughly, Broca's area) underlies the hierarchically organized
combination of elements in the development of both speech and manual
action, including tool use. The neural evidence implicates relatively
specific cortical circuitry underlying a grammatical "module."
Behavioral and neurodevelopmental data suggest that the modular
capacities for language and manipulation are not present at birth but
come into being gradually during the third and fourth years of life.  An
evolutionary homologue of the common neural substrate for language
production and manual action during the first two years of human life is
hypothesized to have provided a foundation for the evolution of language
before the divergence of hominids and the great apes. Support comes from
the discovery of a Broca's area analogue in contemporary primates. In
addition, chimpanzees have an identical constraint on hierarchical
complexity in both tool use and symbol combination. Their performance
matches that of the two-year-old child who has not yet developed the
differentiated neural circuits for the relatively modularized production
of complex grammar and complex manual construction activity.

------------------------------

Subject: Consciousness: BBS Call for Commentators
From:    Stevan Harnad <harnad%phoenix.Princeton.EDU@VM.TCS.Tulane.EDU>
Date:    Fri, 21 Dec 90 12:55:58 -0500

Below is the abstract of a forthcoming target article to appear in
Behavioral and Brain Sciences (BBS), an international, interdisciplinary
journal that provides Open Peer Commentary on important and controversial
current research in the biobehavioral and cognitive sciences.
Commentators must be current BBS Associates or nominated by a current BBS
Associate. To be considered as a commentator on this article, to suggest
other appropriate commentators, or for information about how to become a
BBS Associate, please send email to:

harnad@clarity.princeton.edu  or harnad@pucc.bitnet        or write to:
BBS, 20 Nassau Street, #240, Princeton NJ 08542  [tel: 609-921-7771]

To help us put together a balanced list of commentators, please give some
indication of the aspects of the topic on which you would bring your
areas of expertise to bear if you are selected as a commentator. (The
article is retrievable by anonymous ftp from directory /pub/harnad as
file velmans.bbs on princeton.edu, however, please do not prepare a
commentary unless you have been formally invited to do so.)
____________________________________________________________________
         IS HUMAN INFORMATION PROCESSING CONSCIOUS?

                      Max Velmans
               Department of Psychology
                  Goldsmiths College
                 University of London
           electronic mail: MLV@gold.lon.ac.uk

KEY WORDS: consciousness, information processing, brain, unconscious,
attention, mind, functionalism, reductionism, complementarity.

ABSTRACT: Investigations of the function of consciousness in human
information processing have focused mainly on two questions: (1) where
does consciousness enter into the information processing sequence and (2)
how does conscious processing differ from preconscious and unconscious
processing. Input analysis is thought to be initially "preconscious,"
"pre-attentive," fast, involuntary, and automatic. This is followed by
"conscious," "focal-attentive" analysis which is relatively slow,
voluntary, and flexible. It is thought that simple, familiar stimuli can
be identified preconsciously, but conscious processing is needed to
identify complex, novel stimuli. Conscious processing has also been
thought to be necessary for choice, learning and memory, and the
organization of complex, novel responses, particularly those requiring
planning, reflection, or creativity.

This target article reviews evidence that consciousness performs none of
these functions. Consciousness nearly always results from focal-attentive
processing (as a form of output) but does not itself enter into this or
any other form of human information processing. This suggests that the
term "conscious process" needs re-examination.  Consciousness appears to
be necessary in a variety of tasks because they require focal-attentive
processing; if consciousness is absent, focal-attentive processing is
absent. From a first-person perspective, however, conscious states are
causally effective. First-person accounts are complementary to
third-person accounts. Although they can be translated into third-person
accounts, they cannot be reduced to them.

------------------------------

Subject: Full/Part-Time NN Research Assistant & Programmer Positions
From:    gluck%psych@Forsythe.Stanford.EDU (Mark Gluck)
Date:    Mon, 31 Dec 90 20:50:24 -0800


   Two Full/Part Time Research Assistant Positions in:
   ---------------------------------------------------

           COGNITIVE PSYCHOLOGY / NEURAL NETWORK MODELING

                                 at

                          Rutgers University
             Center for Molecular & Behavioral Neuroscience
                        195 University Avenue
                          Newark, NJ   07102


   Two research positions are available for persons interested in
   pursuing empirical and/or theoretical research in the in cognitive and
   neural sciences.

   The positions are ideal for someone who has just graduated with an
   undergraduate degree and would like a year or two of "hands on"
   experience in research before applying to graduate school in one of
   the cognitive sciences (e.g., neuroscience, psychology, computer
   science).

   We are looking for two people:

    1. RESEARCH PROGRAMMER:

     A person with strong programming skills to work in the development
    of computational theories of the neural & cognitive bases of
    learning. Familiarity with current PDP/neural-network algorithms and
    research would be helpful, as would experience with C/Unix and Sun
    computer systems. Work would either focus on the development of
    network models of human learning and/or biological-circuit models of
    the neural bases of animal learning.

    2. EXPERIMENTAL RESEARCH ASSISTANT:

     A person with experience in running and designing human cognitive
    psychology experiments to work in the design, execution, and data
    analysis of behavioral studies of human categorization learning.
   __________________________________________________________________________

   Other Information:

   FACILITIES: The Center is a new state-funded research center for
    the integrated studies of cognitive, behavioral, and molecular
    neuroscience.  The Center has good computational resources and
    experimental laboratories for behavioral and neural studies.

   LOCATION: The Center is located in Newark, NJ, approximately 20 minutes
    outside of Manhattan, New York (with easy train and subway access to
    midtown and downtown NYC) and close to rural New Jersey countryside.
    Numerous other research centers in the cognitive and neural sciences
    are located nearby, e.g.: Cognitive Science Center, Rutgers/New
    Brunswick; Centers for Cognitive & Neural Science, New York
    University; Cognitive Science Center, Princeton Univ.; Columbia Univ.
    & Medical School; Siemens Corporate Research, Princeton, NJ; NEC
    Research Labs, Princeton, NJ; AT&T Labs; Bellcore; IBM T. J. Watson
    Research Labs.

   CURRENT FACULTY: E. Abercrombie, G. Buzsaki, I. Creese, M. Gluck,
    H. Poizner, R. Siegel, P. Tallal, J. Tepper. Six additional faculty
    will be hired. The center has a total of ten state-funded
    postdoctoral positions and will direct, in collaboration with the
    Institute for Animal Behavior, a graduate program in Behavioral and
    Neural Sciences.
   ----------------------------------------------------------------------------

   For more information on learning research at the CMBN/Rutgers or to
   apply for these post-doctoral positions, please send cover letter with
   a statement of your research interests, a CV, copies of relevant
   preprints, and the the names & phone numbers of references to:

   Dr. Mark A. Gluck                                    Phone: (415) 725-2434
   Dept. of Psychology   <-[Current address to 4/91]      FAX: (415) 725-5699
   Jordan Hall; Bldg. 420
   Stanford University                        email: gluck@psych.stanford.edu
   Stanford, CA  94305-2130


------------------------------

Subject: POSTDOCTORAL POSITION IN NEW YORK AREA: Cognitive & NeuralModels of Human Learning
From:    gluck%psych@Forsythe.Stanford.EDU (Mark Gluck)
Date:    Mon, 31 Dec 90 20:57:22 -0800

 Postdoctoral Positions in:
 --------------------------

                COGNITIVE & NEURAL BASES OF LEARNING

                              at

                       Rutgers University
          Center for Molecular & Behavioral Neuroscience
                     195 University Avenue
                       Newark, NJ   07102


Postdoctoral positions are available for recent Ph.D's in all areas of
Cognitive Science (e.g., Neuroscience, Psychology, Computer Science)
interested in pursuing empirical and/or theoretical research in the
following areas of cognitive and neural science:

      1. COGNITIVE SCIENCE/ADAPTIVE "CONNECTIONIST" NETWORKS:
         Experimental and theoretical (computational) studies of human
         learning and memory.

      2. COMPUTATIONAL NEUROSCIENCE / COGNITIVE NEUROSCIENCE:
         Models of the neural bases of learning in animals and humans.

Candidates with any (or all) of the following skills are particular
encouraged to apply: (1) familiarity with neural network algorithms and
models, (2) strong computational/analytic skills, and (3) experience with
experimental methods, experimental design, and data analysis in cognitive
psychology.
 ----------------------------------------------------------------------------

Other Information:

FACILITIES: The Center is a new state-funded research center for
 the integrated studies of cognitive, behavioral, and molecular neuroscience.
 The Center has good computational resources and experimental laboratories
 for behavioral and neural studies.

LOCATION: The Center is located in Newark, NJ, approximately 20 minutes
 outside of Manhattan, New York (with easy train and subway access to
 midtown and downtown NYC) and close to rural New Jersey countryside.
 Numerous other research centers in the cognitive and neural sciences
 are located nearby including: Cognitive Science Center, Rutgers/New Brunswick;
 Centers for Cognitive & Neural Science, New York University; Cognitive
 Science Center, Princeton Univ.; Columbia Univ. & Medical School; Siemens
 Corporate Research, Princeton, NJ; NEC Research Labs, Princeton, NJ;
 AT&T Labs; Bellcore; IBM T. J. Watson Research Labs.

CURRENT FACULTY: E. Abercrombie, G. Buzsaki, I. Creese, M. Gluck,
 H. Poizner, R. Siegel, P. Tallal, J. Tepper. Six additional faculty
 will be hired. The Center has a total of ten state-funded postdoctoral
 positions and will direct, in collaboration with the Institute for Animal
 Behavior, a graduate program in Behavioral and Neural Sciences.
 ----------------------------------------------------------------------------

For more information on learning research at the CMBN/Rutgers or to apply
for these post-doctoral positions, please send a cover letter with a
statement of your research interests, a CV, copies of relevant preprints,
and the the names & phone numbers of references to:

Dr. Mark A. Gluck                                      Phone: (415) 725-2434
Dept. of Psychology   <-[Current address to 4/91]        FAX: (415) 725-5699
Jordan Hall; Bldg. 420
Stanford University                          email: gluck@psych.stanford.edu
Stanford, CA  94305-2130

------------------------------

Subject: 4th NN Conference. Indiana-Purdue.
From:    SAYEGH%IPFWCVAX.BITNET@vma.CC.CMU.EDU
Date:    Fri, 21 Dec 90 21:55:00 -0500

                        FOURTH CONFERENCE ON NEURAL NETWORKS
                        ------------------------------------
                        AND PARALLEL DISTRIBUTED PROCESSING
                        -----------------------------------

                        INDIANA UNIVERSITY-PURDUE UNIVERSITY
                        ------------------------------------

                                11,12,13 APRIL 1991
                                -------------------

 CALL FOR PAPERS
 ---------------

The Fourth Conference on Neural Networks and Parallel Distributed Processing
at Indiana University-Purdue University will be held on the Fort Wayne Campus,
April 11,12, 13, 1991.

Authors are invited to submit a one page abstract of current research in
their area of Neural Networks Theory or Application before February 5,
1991.  Notification of acceptance or rejection will be sent by February
28.

The proceedings of the third conference are now in press and will be
announced on the network in early January.

Conference registration is $20 and students attend free.  Some limited
financial support might also be available to allow students to attend.

Abstracts and inquiries should be addressed to:


 email: sayegh@ipfwcvax.bitnet
 -----

 US mail:
 -------

Prof. Samir Sayegh
Physics Department
Indiana University-Purdue University
Fort Wayne, IN 46805

FAX:   (219) 481-6880
Voice: (219) 481-6157

------------------------------

End of Neuron Digest [Volume 7 Issue 3]
***************************************