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Interhemispheric visual competition after multisensory reversal of hemianopia
Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
John Wiley and Sons Inc.
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6928431/ https://www.ncbi.nlm.nih.gov/pubmed/31430406 http://dx.doi.org/10.1111/ejn.14554 |
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author | Dakos, Alexander S. Walker, Ellen M. Jiang, Huai Stein, Barry E. Rowland, Benjamin A. |
author_facet | Dakos, Alexander S. Walker, Ellen M. Jiang, Huai Stein, Barry E. Rowland, Benjamin A. |
author_sort | Dakos, Alexander S. |
collection | PubMed |
description | Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex. |
format | Online Article Text |
id | pubmed-6928431 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | John Wiley and Sons Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-69284312020-01-27 Interhemispheric visual competition after multisensory reversal of hemianopia Dakos, Alexander S. Walker, Ellen M. Jiang, Huai Stein, Barry E. Rowland, Benjamin A. Eur J Neurosci Behavioural Neuroscience Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex. John Wiley and Sons Inc. 2019-09-05 2019-12 /pmc/articles/PMC6928431/ /pubmed/31430406 http://dx.doi.org/10.1111/ejn.14554 Text en © 2019 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd. This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Behavioural Neuroscience Dakos, Alexander S. Walker, Ellen M. Jiang, Huai Stein, Barry E. Rowland, Benjamin A. Interhemispheric visual competition after multisensory reversal of hemianopia |
title | Interhemispheric visual competition after multisensory reversal of hemianopia |
title_full | Interhemispheric visual competition after multisensory reversal of hemianopia |
title_fullStr | Interhemispheric visual competition after multisensory reversal of hemianopia |
title_full_unstemmed | Interhemispheric visual competition after multisensory reversal of hemianopia |
title_short | Interhemispheric visual competition after multisensory reversal of hemianopia |
title_sort | interhemispheric visual competition after multisensory reversal of hemianopia |
topic | Behavioural Neuroscience |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6928431/ https://www.ncbi.nlm.nih.gov/pubmed/31430406 http://dx.doi.org/10.1111/ejn.14554 |
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