title: From Foreground to Background: How Task-Neutral Context Influences Contextual Cueing of Visual Search.
abstract: Selective attention determines the effectiveness of implicit contextual learning (e.g., Jiang and Leung, 2005). Visual foreground-background segmentation, on the other hand, is a key process in the guidance of attention (Wolfe, 2003). In the present study, we examined the impact of foreground-background segmentation on contextual cueing of visual search in three experiments. A visual search display, consisting of distractor 'L's and a target 'T', was overlaid on a task-neutral cuboid on the same depth plane (Experiment 1), on stereoscopically separated depth planes (Experiment 2), or spread over the entire display on the same depth plane (Experiment 3). Half of the search displays contained repeated target-distractor arrangements, whereas the other half was always newly generated. The task-neutral cuboid was constant during an initial training session, but was either rotated by 90° or entirely removed in the subsequent test sessions. We found that the gains resulting from repeated presentation of display arrangements during training (i.e., contextual-cueing effects) were diminished when the cuboid was changed or removed in Experiment 1, but remained intact in Experiments 2 and 3 when the cuboid was placed in a different depth plane, or when the items were randomly spread over the whole display but not on the edges of the cuboid. These findings suggest that foreground-background segmentation occurs prior to contextual learning, and only objects/arrangements that are grouped as foreground are learned over the course of repeated visual search.
authors.affiliation: China Centre for Special Economic Zone Research, Research Centre of Brain Function and Psychological Science, Shenzhen UniversityShenzhen, China; General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität MunichMunich, Germany.
authors.forename: Xuelian
authors.initials: X
authors.lastname: Zang
authors.affiliation: General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität Munich Munich, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Geyer
authors.affiliation: General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität Munich Munich, Germany.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Assumpção
authors.affiliation: General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität MunichMunich, Germany; Department of Psychological Science, Birkbeck, University of LondonLondon, UK.
authors.forename: Hermann J
authors.initials: HJ
authors.lastname: Müller
authors.affiliation: General and Experimental Psychology, Department of Psychology, Ludwig-Maximilians-Universität Munich Munich, Germany.
authors.forename: Zhuanghua
authors.initials: Z
authors.lastname: Shi
keywords: 3D visual search; contextual cueing; foreground-background segmentation; grouping; implicit learning; spatial memory