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Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions
Current initiatives to restore vision emphasize the need for objective assessments of visual field (VF) defects as pursued with functional magnetic resonance imaging (fMRI) approaches. Here, we compared population receptive field (pRF) mapping-based VF reconstructions to an fMRI method that uses mor...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Frontiers Media S.A.
2021
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8455880/ https://www.ncbi.nlm.nih.gov/pubmed/34566575 http://dx.doi.org/10.3389/fnins.2021.745886 |
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author | Prabhakaran, Gokulraj T. Al-Nosairy, Khaldoon O. Tempelmann, Claus Thieme, Hagen Hoffmann, Michael B. |
author_facet | Prabhakaran, Gokulraj T. Al-Nosairy, Khaldoon O. Tempelmann, Claus Thieme, Hagen Hoffmann, Michael B. |
author_sort | Prabhakaran, Gokulraj T. |
collection | PubMed |
description | Current initiatives to restore vision emphasize the need for objective assessments of visual field (VF) defects as pursued with functional magnetic resonance imaging (fMRI) approaches. Here, we compared population receptive field (pRF) mapping-based VF reconstructions to an fMRI method that uses more robust visual stimulation (on-off block design) in combination with individualized anatomy-driven retinotopic atlas-information (atlas-based VF). We investigated participants with sizable peripheral VF-deficits due to advanced glaucoma (n = 4) or retinitis pigmentosa (RP; n = 2) and controls (n = 6) with simulated scotoma. We obtained (1) standard automated perimetry (SAP) data as reference VFs and 3T fMRI data for (2) pRF-mapping [8-direction bar stimulus, fixation color change task] and (3) block-design full-field stimulation [8-direction drifting contrast patterns during (a) passive viewing (PV) and (b) one-back-task (OBT; reporting successions of identical motion directions) to probe the impact of previously reported task-related unspecific visual cortex activations]. Correspondence measures between the SAP and fMRI-based VFs were accuracy, assisted by sensitivity and specificity. We found an accuracy of pRF-based VF from V1 in patients [median: 0.62] that was similar to previous reports and increased by adding V2 and V3 to the analysis [0.74]. In comparison to the pRF-based VF, equivalent accuracies were obtained for the atlas-based VF for both PV [0.67] and, unexpectedly, the OBT [0.59], where, however, unspecific cortical activations were reflected by a reduction in sensitivity [0.71 (PV) and 0.35 (OBT)]. In conclusion, in patients with peripheral VF-defects, we demonstrate that previous fMRI procedures to obtain VF-estimates might be enhanced by: (1) pooling V1-V3 to enhance accuracy; (2) reporting sensitivity and specificity measures to increase transparency of the VF-reconstruction metric; (3) applying atlas-based procedures, if pRF-based VFs are not available or difficult to obtain; and (4) giving, counter-intuitively, preference to PV. These findings are expected to provide guidance to overcome current limitations of translating fMRI-based methods to a clinical work-up. |
format | Online Article Text |
id | pubmed-8455880 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | Frontiers Media S.A. |
record_format | MEDLINE/PubMed |
spelling | pubmed-84558802021-09-23 Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions Prabhakaran, Gokulraj T. Al-Nosairy, Khaldoon O. Tempelmann, Claus Thieme, Hagen Hoffmann, Michael B. Front Neurosci Neuroscience Current initiatives to restore vision emphasize the need for objective assessments of visual field (VF) defects as pursued with functional magnetic resonance imaging (fMRI) approaches. Here, we compared population receptive field (pRF) mapping-based VF reconstructions to an fMRI method that uses more robust visual stimulation (on-off block design) in combination with individualized anatomy-driven retinotopic atlas-information (atlas-based VF). We investigated participants with sizable peripheral VF-deficits due to advanced glaucoma (n = 4) or retinitis pigmentosa (RP; n = 2) and controls (n = 6) with simulated scotoma. We obtained (1) standard automated perimetry (SAP) data as reference VFs and 3T fMRI data for (2) pRF-mapping [8-direction bar stimulus, fixation color change task] and (3) block-design full-field stimulation [8-direction drifting contrast patterns during (a) passive viewing (PV) and (b) one-back-task (OBT; reporting successions of identical motion directions) to probe the impact of previously reported task-related unspecific visual cortex activations]. Correspondence measures between the SAP and fMRI-based VFs were accuracy, assisted by sensitivity and specificity. We found an accuracy of pRF-based VF from V1 in patients [median: 0.62] that was similar to previous reports and increased by adding V2 and V3 to the analysis [0.74]. In comparison to the pRF-based VF, equivalent accuracies were obtained for the atlas-based VF for both PV [0.67] and, unexpectedly, the OBT [0.59], where, however, unspecific cortical activations were reflected by a reduction in sensitivity [0.71 (PV) and 0.35 (OBT)]. In conclusion, in patients with peripheral VF-defects, we demonstrate that previous fMRI procedures to obtain VF-estimates might be enhanced by: (1) pooling V1-V3 to enhance accuracy; (2) reporting sensitivity and specificity measures to increase transparency of the VF-reconstruction metric; (3) applying atlas-based procedures, if pRF-based VFs are not available or difficult to obtain; and (4) giving, counter-intuitively, preference to PV. These findings are expected to provide guidance to overcome current limitations of translating fMRI-based methods to a clinical work-up. Frontiers Media S.A. 2021-09-08 /pmc/articles/PMC8455880/ /pubmed/34566575 http://dx.doi.org/10.3389/fnins.2021.745886 Text en Copyright © 2021 Prabhakaran, Al-Nosairy, Tempelmann, Thieme and Hoffmann. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
spellingShingle | Neuroscience Prabhakaran, Gokulraj T. Al-Nosairy, Khaldoon O. Tempelmann, Claus Thieme, Hagen Hoffmann, Michael B. Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions |
title | Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions |
title_full | Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions |
title_fullStr | Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions |
title_full_unstemmed | Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions |
title_short | Mapping Visual Field Defects With fMRI – Impact of Approach and Experimental Conditions |
title_sort | mapping visual field defects with fmri – impact of approach and experimental conditions |
topic | Neuroscience |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8455880/ https://www.ncbi.nlm.nih.gov/pubmed/34566575 http://dx.doi.org/10.3389/fnins.2021.745886 |
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