Behavior Research Methods vol:46 issue:2 pages:472-487
Neuropsychological diagnostic tests of visual perception mostly assess high level processes like object recognition. Object recognition, however, relies on distinct mid level processes of perceptual organization that are only implicitly tested in classical tests. Therefore, we developed the Leuven Perceptual Organization Screening Test (L-POST) in which a wide range of processes of perceptual organization are measured independently. The L-POST consists of 15 subtests screening for various aspects of perceptual organization, e.g. figure-ground segregation, contour integration, embedded figure detection, biological motion, perceptual grouping, local and global processing, scene segmentation and texture segmentation. To reduce cognitive load a matching-to-sample task is used for all test items: Participants have to indicate the alternative that is the most similar to the target stimulus. The computerized test can be administered in 20-30 minutes, and a neglect friendly version is available. The L-POST is a potentially valuable screening test for perceptual organization. In clinical practice the L-POST can be administered to differentiate between mid-level deficits in perceptual organization and high-level deficits like object recognition. In addition, it offers a useful tool for researchers in identifying patients for neuropsychological research. The L-POST is freely available at www.gestaltrevision.be/tests.