From: Rajeev Raizada <rajeev@cns.bu.edu>
To: cvnet@lawton.ewind.com
Cc: Rajeev Raizada <rajeev@cns.bu.edu>
Subject: Laminar V1 model preprint downloadable (Grossberg/Raizada)
Dear Dr. Chan,
Please could you post the following preprint announcement to CVNet.
Many thanks,
Rajeev Raizada
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A preprint of the following paper is now downloadable in PDF or
gzipped PostScript formats at:
http://cns-web.bu.edu/~rajeev/index.html#publications
S. Grossberg and R. D. S. Raizada (1999) Contrast-sensitive perceptual
grouping and object-based attention in the laminar circuits of primary
visual cortex. Vision Research, forthcoming.
Abstract:
Recent neurophysiological studies have shown that primary visual cortex,
or V1, does more than passively process image features using the
feedforward filters suggested by Hubel and Wiesel. It also uses horizontal
interactions to group features preattentively into object representations,
and feedback interactions to selectively attend to these groupings. All
neocortical areas, including V1, are organized into layered circuits. We
present a neural model showing how the layered circuits in areas V1 and V2
enable feedforward, horizontal, and feedback interactions to complete
perceptual groupings over positions that do not receive contrastive visual
inputs, even while attention can only modulate or prime positions that do
not receive such inputs. Recent neurophysiological data about how grouping
and attention occur and interact in V1 are simulated and explained, and
testable predictions are made. These simulations show how attention can
selectively propagate along an object grouping and protect it from
competitive masking, and how contextual stimuli can enhance or suppress
groupings in a contrast-sensitive manner.
Please let me know if you have any problems with downloading the
preprint.
Yours,
Rajeev Raizada
Dept. of Cognitive and Neural Systems
Boston University
677 Beacon St.
Boston, MA 02215.
Tel: 617-353-6181
Fax: 617-353-7755
E.mail: rajeev@cns.bu.edu
WWW: http://cns-web.bu.edu/~rajeev