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[Eric Chown]

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The following paper has been added to the archive:

   Tracing Recurrent Activity in Cognitive Elements (TRACE):
        A Model of Temporal Dynamics in a Cell Assembly

              Stephen Kaplan, Martin Sonntag and Eric Chown
    Department of Electrical Engineering and Computer Science, and Department
            of Psychology, The University of Michigan
                  
The article appeared in Connection Science 3:179-206 (1991)

Abstract:  Hebb's introduction of the cell assembly concept marks the beginning of
modern connectionism, yet its implications remail largely unexplored and its
potential unexploited.  Lately, however, promising efforts have been made to
utilize recurrent connections, suggesting the timeliness of a reexamination of
the cell assembly as a key element in a cognitive connectionism.  Our approach
emphasizes the psychological functions of activity in a cell assembly.  This
provides an opportunity to explore the dynamic behavior of the cell assembly
considered as a continuous system, an important topic that we feel has not been
given sufficient attention.  A step-by-step analysis leads to an identification of
characteristic temporal patterns and of necessary control systems.  Each step of
this analysis leads to a corresponding building block in a set of emerging
equations.  A series of experiments is then described that explore the implications
of the theoretically derived equations in terms of the time course of activity 
generated by a simulation under different conditions.  Finally the model is 
evaluated in terms of whether the various contraints deemed appropriate can be
met, whether the resulting solution is robust, and whether the solution promises
sufficient utility and generality.          

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This paper has been placed in the neuroprose directory in compressed form.  The
file name is kaplan.trace.ps.Z 

If your are unable to ftp this paper please address reprint requests to:
   Professor Stephen Kaplan
   Psychological Laboratories
   Mason Hall
   The University of Michigan
   Ann Arbor, MI 48109-1027

   e-mail:  Stephen_Kaplan at um.cc.umich.edu

Here is how to ftp this paper:

unix> ftp cheops.cis.ohio-state.edu (or 128.146.8.62)
Name: anonymous
Password: neuron
ftp> cd pub/neuroprose
ftp> binary
ftp> get kaplan.trace.ps.Z
ftp> quit
unix> uncompress kaplan.trace.ps.Z
unix> lpr kaplan.trace.ps