Abstract
Objective: Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere. However, attentional effects of more posterior lesions are less clear. The aim of this study was to characterize visual processing speed and apprehension span following posterior cerebral artery (PCA) stroke. We also relate these attentional parameters to visual word recognition, as previous studies have suggested that reduced visual speed and span may explain pure alexia.
Methods: Nine patients with MR-verified focal lesions in the PCA-territory (four left PCA; four right PCA; one bilateral, all >1 year post stroke) were compared to 25 controls using single case statistics. Visual attention was characterized
by a whole report paradigm allowing for hemifield-specific speed and span measurements. We also characterized visual field defects and reading performance.
Results: Four patients showed bilateral reductions in visual span despite unilateral lesions (2L; 2R). Five patients showed selective deficits in visual span, with speed unaffected in the same field (ipsi-or contralesionally). Only patients with right hemifield reductions in visual span were impaired in reading, and this could follow either right or left lateralized stroke.
Conclusion: Visual span may be affected bilaterally by unilateral PCA-lesions. Reductions in visual span may also be confined to one hemifield, and may be affected in spite of preserved visual processing speed. Furthermore, reduced
span in the right visual field seems to be related to reading impairment in this group, regardless of lesion lateralization.
Originalsprog | Engelsk |
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Publikationsdato | 2015 |
Status | Udgivet - 2015 |
Begivenhed | The 5 th Conference of the European Societies of Neuropsychology - Tampere, Finland Varighed: 9 sep. 2015 → 11 sep. 2015 |
Konference
Konference | The 5 th Conference of the European Societies of Neuropsychology |
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Land/Område | Finland |
By | Tampere |
Periode | 09/09/2015 → 11/09/2015 |