Paper available: Simulation of visual cortex...

[Bob Soodak]

The following reprint is now available:

FTP-host: archive.cis.ohio-state.edu
FTP-file: /pub/neuroprose/soodak.suture.ps.Z

Author: R. Soodak
	Rockefeller University

Title: Simulation of visual cortex development under lid-suture
       conditions: Enhancement of response specificity by a
       reverse-Hebb rule in the absence of spatially patterned input

Size: 15 pages

Published in Biological Cybernetics 70, 303-309 (1994)
(Due to copyright restrictions the manuscript could not be posted prior
to publication.)

Abstract:

In this report, I show that a reverse-Hebb synaptic modification rule
leads to the enhancement of response specificity of simulated visual
cortex neurons in the absence of spatial patterning of the afferent
activity.  Although it is clear that receptive fields in the visual
cortex can be modified by experience, many studies have shown a
substantial increase of response specificity in cats deprived of
pattern vision by lid suture, leading some to conclude that receptive
field properties are essentially hard-wired. The hard-wired vs.
experience-dependent controversy can be resolved by assuming that while
Hebb-type plasticity is responsible for developmental synaptic changes,
the organization of presynaptic activity which exists under conditions
of visual deprivation is sufficient to drive the neurons towards
greater specificity (Linsker 1986a-c; Miller 1989, 1992; Miller et al.
1989).  As a reverse-Hebb rule enhances response specificity by
balancing the push-pull system of ON- and OFF-center afferents, the
sufficient condition is that the activity of ON- and OFF-center retinal
ganglion cells be negatively correlated, a condition which will be met
by diffuse illumination as seen through sutured eyelids.  Unlike the
models of Linsker and Miller and colleagues, which are based on a
standard-Hebb rule, the model presented here does not require the
presence of a "Mexican hat" spatial patterning of the afferent
correlations, which has not been observed experimentally.

To retrieve the file:

 unix> ftp archive.cis.ohio-state.edu
 Name: anonymous
 Password: your full email address
 ftp> cd pub/neuroprose
 ftp> binary
 ftp> get soodak.suture.ps.Z
 ftp> bye

 unix> uncompress soodak.suture.ps.Z
 unix> lpr soodak.suture.ps

For hard copy please send name and address in a form suitable for use
as a mailing label to:

 Robert Soodak
 Rockefeller Univ.
 1230 York Ave.
 New York, NY  10021
 USA