Eye movements during scene inspection: A test of the saliency map hypothesis

Abstract

What attracts attention when we inspect a scene? Two experiments recorded eye movements while viewers inspected pictures of natural office scenes in which two objects of interest were placed. One object had low contour density and uniform colouring (a piece of fruit), relative to another that was visually complex (for example, coffee mugs and commercial packages). In each picture the visually complex object had the highest visual saliency according to the Itti and Koch algorithm. Two experiments modified the task while the pictures were inspected, to determine whether visual saliency is invariably dominant in determining the pattern of fixations, or whether the purpose of inspection can provide a cognitive override that renders saliency secondary. In the first experiment viewers inspected the scene in preparation for a memory task, and the more complex objects were potent in attracting early fixations, in support of a saliency map model of scene inspection. In the second experiment viewers were set the task of detecting the presence of a low saliency target, and the effect of a high saliency distractor was negligible, supporting a model in which the saliency map can be built with cognitive influences that override low-level visual features.

A preliminary report of this investigation was presented at the meeting of Experimental Psychology Society at the London meeting in January 2005.

A preliminary report of this investigation was presented at the meeting of Experimental Psychology Society at the London meeting in January 2005.

Acknowledgments

We are grateful to Laurent Itti for use of software for the measurement of visual saliency, to Jan Theeuwes, Andrew Hollingworth, Marc Brysbaert, Peter De Graef, and two anonymous reviewers for their comments on previous drafts of this paper, and to the Nuffield Foundation for award URB/01455/G that enabled us to complete this project.

Notes

A preliminary report of this investigation was presented at the meeting of Experimental Psychology Society at the London meeting in January 2005.