| Motion direction discrimination in blind hemifields. | |
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MedLine Citation:
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PMID: 9029075 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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We tested motion direction discrimination with random dot cinematograms (RDCs) projected into the contralateral homonymous visual field defects of 10 patients with unilateral cerebral hemispheric lesions. Five patients had medial occipital lesions that spared the putative motion area in lateral occipitotemporal cortex and the optic radiations and other white matter tracts proximal to this site. The other 5 had lesions involving this area or the proximal optic radiations. Eye position was monitored to ensure fixation. No patient in either group discriminated motion direction in signal/noise RDCs at a level better than chance, and the performance of those with lesions restricted to medial occipital lobe did not differ from those with lateral occipital or optic radiation lesions. A subgroup of patients with medial occipital lesions also performed a "frequency of discrimination" experiment, using 100% coherent dot motion with stimulus velocities ranging as high as 79.4 degrees/sec. Their results on these tests were also no better than chance. Sparing of the putative motion area in lateral occipitotemporal cortex and its input fibers is not a sufficient condition for residual direction discrimination (blindsight) with RDCs in homonymous visual field defects. |
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Authors:
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J J Barton; J A Sharpe |
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Publication Detail:
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Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
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Title: Annals of neurology Volume: 41 ISSN: 0364-5134 ISO Abbreviation: Ann. Neurol. Publication Date: 1997 Feb |
Date Detail:
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Created Date: 1997-03-12 Completed Date: 1997-03-12 Revised Date: 2006-11-15 |
Medline Journal Info:
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Nlm Unique ID: 7707449 Medline TA: Ann Neurol Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: 255-64 Citation Subset: IM |
Affiliation:
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Division of Neurology, The Toronto Hospital, University of Toronto, Ontario, Canada. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Adult Aged Cerebral Infarction / physiopathology* Discrimination (Psychology) / physiology* Female Humans Male Middle Aged Motion* Visual Fields / physiology* |
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