Pathological completion in the intact visual field of hemianopia patients

Paramei, Galina V. and Favrod, Ophélie and Sabel, Bernhard A. and Herzog, Michael H. (2017) Pathological completion in the intact visual field of hemianopia patients. Visual Cognition, 25 (17). pp. 169-183. ISSN 1350-6285

Text Paramei et al_Visual Cognition 2017_preprint.pdf - Accepted Version Download (3MB)

Abstract

We investigated figure segregation in the intact visual field (VF) of hemianopia patients. Three patients and matched controls performed a Yes–No figure detection task, where square or square fragments were embedded in a background of randomly oriented Gabor elements. We varied orientation and number of the fragment elements, stimulus eccentricity and background density (BD). Figure detection was impaired in all three patients in the entire intact VF, but potentially more pronounced in patients with cortical lesions. “Pathological completion” was most frequently observed for high BDs and for square fragments oriented towards the blind hemifield. Our findings confirm contour integration deficits in the intact VF of hemianopia patients. Further, our results indicate that (1) contour integration deficits are exacerbated by contextual interaction and (2) “pathological completion” appears to be more likely associated with lesions of cortical rather than geniculo-striate origin. The deficits point to increased lateral suppressive inputs from background elements.

Item Type:	Article
Additional Information and Comments:	This is an Author's Original Manuscript of an article submitted for consideration in the Visual Cognition. Copyright Taylor & Francis. Visual Cognition is available online at http://www.tandfonline.com/doi/full/10.1080/13506285.2017.1352056
Keywords:	Hemianopia, intact visual field, contour integration, pathological completion, contextual integration
Faculty / Department:	Faculty of Human and Digital Sciences > School of Psychology
Depositing User:	Galina Paramei
Date Deposited:	12 Sep 2017 15:13
Last Modified:	16 Mar 2020 12:17
URI:	https://hira.hope.ac.uk/id/eprint/2138

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