Preprint announcement

[Steven J. Nowlan]

****** PAPER AVAILABLE VIA NEUROPROSE ***************************************
****** PLEASE DO NOT FORWARD TO OTHER MAILING LISTS OR BOARDS.  THANK YOU. **

The following paper has been placed in the Neuroprose
archives at Ohio State. The file is nowlan.vismotion.ps.Z.
Ftp instructions follow the abstract. Only an electronic version of this
paper is available. This is a preprint of the paper to appear in the NIPS 5
proceedings due out later this year.


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

    Filter Selection Model for Generating Visual Motion Signals

                       Steven J. Nowlan
		             and
 		     Terrence J. Sejnowski
                Computational Neurobiology Laboratory
                      The Salk Institute
                        P.O. Box 5800
                     San Diego, CA 92186-5800


                            ABSTRACT:

Neurons in area MT of primate visual cortex encode the velocity of moving
objects. We present a model of how MT cells aggregate responses from V1 to
form such a velocity representation.  Two different sets of units, with local
receptive fields, receive inputs from motion energy filters. One set of units
forms estimates of local motion, while the second set computes the utility of
these estimates.  Outputs from this second set of units ``gate'' the outputs
from the first set through a gain control mechanism.  This active process for
selecting only a subset of local motion responses to integrate into more
global responses distinguishes our model from previous models of velocity
estimation.  The model yields accurate velocity estimates in synthetic images
containing multiple moving targets of varying size, luminance, and spatial
frequency profile and deals well with a number of transparency phenomena.


      -----------------------------------------------------
                        FTP INSTRUCTIONS

Either use "Getps nowlan.vismotion.ps.Z", or do the following:

     unix> ftp archive.cis.ohio-state.edu (or 128.146.8.52)
     Name: anonymous
     Password: neuron
     ftp> cd pub/neuroprose
     ftp> binary
     ftp> get nowlan.vismotion.ps.Z
     ftp> quit
     unix> uncompress nowlan.vismotion.ps.Z
     unix> lpr -s nowlan.vismotion.ps (or however you print postscript)


Steven J. Nowlan
Computational Neurobiology Laboratory
The Salk Institute
P.O. Box 85800
San Diego, CA
92186-5800

Work Phone: 619-453-4100 X124
e-mail:  nowlan at helmholtz.sdsc.edu