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Modeling the temporal dynamics of IT neurons in visual search: A mechanism for top-down selective attention

Usher, Marius and Niebur, Ernst (1996) Modeling the temporal dynamics of IT neurons in visual search: A mechanism for top-down selective attention. Journal of Cognitive Neuroscience, 8 (4). pp. 311-327. ISSN 0898-929X. doi:10.1162/jocn.1996.8.4.311.

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We propose a neural model for object-oriented attention in which various visual stimuli (shapes, colors, letters, etc.) are represented by competing, mutually inhibitory, cell assemblies. The model's response to a sequence of cue and target stimuli mimics the neural responses in infero temporal (IT) visual cortex of monkeys performing a visual search task: enhanced response during the display of the stimulus, which decays but remains above a spontaneous rate after the cue disappears. When, subsequently, a display consisting of the target and several distractors is presented, the activity of all stimulus-driven cells is initially enhanced. After a short period of time, however, the activity of the cell assembly representing the cue stimulus is enhanced while the activity of the distractors decays because of mutual competition and a small top-down “expectational” input. The model fits the measured delayed activity in IT-cortex, recently reported by Chelazzi, Miller, Duncan, and Desimone (1993a), and we suggest that such a process, which is largely independent of the number of distractors, may be used by the visual system for selecting an expected target (appearing at an uncertain location) among distractors.

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Additional Information:Fall 1996, Vol. 8, No. 4, Pages 311-327. Posted Online December 13, 2007. c1996 Massachusetts Institute of Technology. M.U. was supported by the National Institute of Mental Health (Grants MH47566 and MH45156) and E.N. by grants from the NSF, AFOSR, and ONR to Christof Koch. We wish to thank Jonathan Cohen, Christof Koch, and James McClelland for in- sightful discussions and support, Jochen Braun for a critical reading of the manuscript, and Bob Desimone and Leonardo Chelazzi for stimulating comments.
Group:Koch Laboratory (KLAB)
Funding AgencyGrant Number
National Institute of Mental HealthMH47566
National Institute of Mental HealthMH45156
U.S. Office of Naval ResearchUNSPECIFIED
Issue or Number:4
Record Number:CaltechAUTHORS:20130816-103233842
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Official Citation: Modeling the Temporal Dynamics of IT Neurons in Visual Search: A Mechanism for Top-Down Selective Attention Marius Usher and Ernst Niebur Journal of Cognitive Neuroscience 1996 8:4, 311-327
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:40532
Deposited By: KLAB Import
Deposited On:05 Feb 2008 23:30
Last Modified:09 Nov 2021 23:49

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