title: Effects of task-irrelevant grouping on visual selection in partial report.
abstract: Perceptual grouping modulates performance in attention tasks such as partial report and change detection. Specifically, grouping of search items according to a task-relevant feature improves the efficiency of visual selection. However, the role of task-irrelevant feature grouping is not clearly understood. In the present study, we investigated whether grouping of targets by a task-irrelevant feature influences performance in a partial-report task. In this task, participants must report as many target letters as possible from a briefly presented circular display. The crucial manipulation concerned the color of the elements in these trials. In the sorted-color condition, the color of the display elements was arranged according to the selection criterion, and in the unsorted-color condition, colors were randomly assigned. The distractor cost was inferred by subtracting performance in partial-report trials from performance in a control condition that had no distractors in the display. Across five experiments, we manipulated trial order, selection criterion, and exposure duration, and found that attentional selectivity was improved in sorted-color trials when the exposure duration was 200 ms and the selection criterion was luminance. This effect was accompanied by impaired selectivity in unsorted-color trials. Overall, the results suggest that the benefit of task-irrelevant color grouping of targets is contingent on the processing locus of the selection criterion.
authors.affiliation: Center for Visual Cognition, Department of Psychology, University of Copenhagen, Copenhagen, Denmark. rasmus.lunau@psy.ku.dk.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Lunau
authors.affiliation: Center for Visual Cognition, Department of Psychology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Habekost
mesh_terms: D000328:Adult; D001288:Attention; D003116:Color; D005260:Female; D006801:Humans; D008297:Male; D013647:Task Performance and Analysis; D014796:Visual Perception; D055815:Young Adult
keywords: Partial report; Perceptual grouping; Selective attention