The Lifetime of Salience Extends Beyond the Initial Saccade

Area of Science:

• Cognitive Psychology
• Neuroscience
• Computational Vision

Background:

• Models of visual search predict saccades are biased toward conspicuous (salient) objects.
• Previous research indicated this bias is limited to initial saccades, based on orientation contrast.
• This finding conflicts with influential salience models of visual attention.

Purpose of the Study:

• To investigate if the bias toward conspicuous objects for the second saccade generalizes beyond orientation contrast.
• To examine the role of feature contrast type and peripheral target discriminability in saccadic selection.

Main Methods:

• Experiment 1: Assessed second saccade bias toward conspicuous luminance annuli when the target was not peripherally discriminable.
• Experiment 2: Assessed second saccade bias when the target was peripherally discriminable.
• Manipulated feature contrast (luminance) and peripheral target discriminability.

Main Results:

• A significant bias toward the most conspicuous candidate was observed for the second saccade in Experiment 1.
• This bias was absent in Experiment 2 when the target was peripherally discriminable.
• Second saccade selection is influenced by object conspicuity beyond initial saccades.

Conclusions:

• Conspicuity influences saccadic selection beyond the initial eye movement.
• The role of conspicuity in second saccades depends on the type of feature contrast and peripheral target discriminability.
• Findings challenge the notion that salience effects are limited to short-latency initial saccades.