BIROn - Birkbeck Institutional Research Online

    Preattentive surface and contour grouping in Kanizsa figures: evidence from parietal extinction

    Conci, M. and Bobel, E. and Matthias, E. and Keller, I. and Muller, Hermann J. and Finke, K. (2009) Preattentive surface and contour grouping in Kanizsa figures: evidence from parietal extinction. Neuropsychologia 47 (3), pp. 726-732. ISSN 0028-3932.

    Full text not available from this repository.


    Visual extinction commonly occurs after unilateral, parietal brain damage and manifests in a failure to identify contralesional stimuli when presented simultaneously with other, ipsilesional stimuli – but full awareness for single stimulus presentations. However, extinction can be substantially reduced when preattentive grouping operations link fragmentary items across hemifields into a coherent object. For instance, one study demonstrated preserved access to bilateral stimulus segments when these could be grouped to form a Kanizsa square [Mattingley, J. B., Davis, G., & Driver, J. (1997). Preattentive filling-in of visual surfaces in parietal extinction. Science, 275, 671–674]. Here, we investigated the relative contributions of distinct object attributes to the spared access in Kanizsa figure completion in extinction, by systematically varying the degree to which bilateral surface filling-in and contour interpolations group disparate items. We demonstrate that surface information can substantially reduce extinction, whereas contour completions showed comparably smaller influences. In summary, such graded influences of object attributes support recurrent models of grouping, first, linking fragmentary parts into coherent surfaces and, second, interpolating the precise boundaries.


    Item Type: Article
    Keyword(s) / Subject(s): Spatial neglect, extinction, visual attention, perceptual grouping, illusory contours, surface segmentation
    School: Birkbeck Faculties and Schools > Faculty of Science > School of Psychological Sciences
    Depositing User: Administrator
    Date Deposited: 17 Dec 2010 14:50
    Last Modified: 02 Aug 2023 16:53


    Activity Overview
    6 month trend
    6 month trend

    Additional statistics are available via IRStats2.

    Archive Staff Only (login required)

    Edit/View Item Edit/View Item