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Evidence for two distinct mechanisms directing gaze in natural scenes

Mackay, Michael and Cerf, Moran and Koch, Christof (2012) Evidence for two distinct mechanisms directing gaze in natural scenes. Journal of Vision, 12 (4). p. 9. ISSN 1534-7362. doi:10.1167/12.4.9.

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Various models have been proposed to explain the interplay between bottom-up and top-down mechanisms in driving saccades rapidly to one or a few isolated targets. We investigate this relationship using eye-tracking data from subjects viewing natural scenes to test attentional allocation to high-level objects within a mathematical decision-making framework. We show the existence of two distinct types of bottom-up saliency to objects within a visual scene, which disappear within a few fixations, and modification of this saliency by top-down influences. Our analysis reveals a subpopulation of early saccades, which are capable of accurately fixating salient targets after prior fixation within the same image. These data can be described quantitatively in terms of bottom-up saliency, including an explicit face channel, weighted by top-down influences, determining the mean rate of rise of a decision-making model to a threshold that triggers a saccade. These results are compatible with a rapid subcortical pathway generating accurate saccades to salient targets after analysis by cortical mechanisms.

Item Type:Article
Related URLs:
URLURL TypeDescription
Koch, Christof0000-0001-6482-8067
Additional Information:© 2012 Association for Research in Vision and Ophthalmology. Received March 9, 2011; published April 17, 2012. This work was funded by the Mathers Foundation, ONR, DARPA, and NSF. Author contributions: Co-authors Moran Cerf and Michael Mackay contributed equally to this work. Commercial relationships: none.
Funding AgencyGrant Number
G. Harold and Leila Y. Mathers Charitable FoundationUNSPECIFIED
Office of Naval Research (ONR)UNSPECIFIED
Defense Advanced Research Projects Agency (DARPA)UNSPECIFIED
Subject Keywords:eye-tracking; natural scenes; saliency; saccadic latency; drift diffusion model
Issue or Number:4
Record Number:CaltechAUTHORS:20120605-104655889
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Official Citation:Mackay, M., Cerf, M., & Koch, C. (2012). Evidence for two distinct mechanisms directing gaze in natural scenes. Journal of Vision, 12(4):9, 1–12,, doi:10.1167/12.4.9.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:31812
Deposited By: Jason Perez
Deposited On:05 Jun 2012 20:45
Last Modified:09 Nov 2021 20:01

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