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Relating spatial and temporal orientation pooling to population decoding solutions in human vision

Spatial pooling is often considered synonymous with averaging (or other statistical combinations) of local information contained within a complex visual image. We have recently shown, however, that spatial pooling of motion signals is better characterized in terms of optimal decoding of neuronal pop...

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Detalles Bibliográficos
Autores principales: Webb, Ben S., Ledgeway, Timothy, McGraw, Paul V.
Formato: Texto
Lenguaje:English
Publicado: Elsevier Science Ltd 2010
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2982753/
https://www.ncbi.nlm.nih.gov/pubmed/20447413
http://dx.doi.org/10.1016/j.visres.2010.04.019
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author Webb, Ben S.
Ledgeway, Timothy
McGraw, Paul V.
author_facet Webb, Ben S.
Ledgeway, Timothy
McGraw, Paul V.
author_sort Webb, Ben S.
collection PubMed
description Spatial pooling is often considered synonymous with averaging (or other statistical combinations) of local information contained within a complex visual image. We have recently shown, however, that spatial pooling of motion signals is better characterized in terms of optimal decoding of neuronal populations rather than image statistics (Webb et al., 2007). Here we ask which computations guide the spatial and temporal pooling of local orientation signals in human vision. The observers’ task was to discriminate which of two texture patterns had a more clockwise global orientation. Standard textures had a common orientation; comparison textures were chosen independently from a skewed (asymmetrical) probability distribution with distinct spatial or temporal statistics. We simulated observers’ performance using different estimators (vector average, winner-takes-all and maximum likelihood) to decode the orientation-tuned activity of a population of model neurons. Our results revealed that the perceived global orientation of texture patterns coincided with the mean (or vector average read-out) of orientation signals accumulated over both space and time. To reconcile these results with our previous work on direction pooling, we varied stimulus duration. Perceived global orientation was accurately predicted by a vector average read-out of orientation signals at relatively short stimulus durations and maximum likelihood read-out at longer durations. Moreover, decreasing the luminance contrast of texture patterns increased the duration of the transition from a vector average to maximum likelihood read-out. Our results suggest that direction and orientation pooling use similar probabilistic read-out strategies when sufficient time is available.
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spelling pubmed-29827532010-12-06 Relating spatial and temporal orientation pooling to population decoding solutions in human vision Webb, Ben S. Ledgeway, Timothy McGraw, Paul V. Vision Res Article Spatial pooling is often considered synonymous with averaging (or other statistical combinations) of local information contained within a complex visual image. We have recently shown, however, that spatial pooling of motion signals is better characterized in terms of optimal decoding of neuronal populations rather than image statistics (Webb et al., 2007). Here we ask which computations guide the spatial and temporal pooling of local orientation signals in human vision. The observers’ task was to discriminate which of two texture patterns had a more clockwise global orientation. Standard textures had a common orientation; comparison textures were chosen independently from a skewed (asymmetrical) probability distribution with distinct spatial or temporal statistics. We simulated observers’ performance using different estimators (vector average, winner-takes-all and maximum likelihood) to decode the orientation-tuned activity of a population of model neurons. Our results revealed that the perceived global orientation of texture patterns coincided with the mean (or vector average read-out) of orientation signals accumulated over both space and time. To reconcile these results with our previous work on direction pooling, we varied stimulus duration. Perceived global orientation was accurately predicted by a vector average read-out of orientation signals at relatively short stimulus durations and maximum likelihood read-out at longer durations. Moreover, decreasing the luminance contrast of texture patterns increased the duration of the transition from a vector average to maximum likelihood read-out. Our results suggest that direction and orientation pooling use similar probabilistic read-out strategies when sufficient time is available. Elsevier Science Ltd 2010-10-28 /pmc/articles/PMC2982753/ /pubmed/20447413 http://dx.doi.org/10.1016/j.visres.2010.04.019 Text en © 2010 Elsevier Ltd. https://creativecommons.org/licenses/by/3.0/ Open Access under CC BY 3.0 (https://creativecommons.org/licenses/by/3.0/) license
spellingShingle Article
Webb, Ben S.
Ledgeway, Timothy
McGraw, Paul V.
Relating spatial and temporal orientation pooling to population decoding solutions in human vision
title Relating spatial and temporal orientation pooling to population decoding solutions in human vision
title_full Relating spatial and temporal orientation pooling to population decoding solutions in human vision
title_fullStr Relating spatial and temporal orientation pooling to population decoding solutions in human vision
title_full_unstemmed Relating spatial and temporal orientation pooling to population decoding solutions in human vision
title_short Relating spatial and temporal orientation pooling to population decoding solutions in human vision
title_sort relating spatial and temporal orientation pooling to population decoding solutions in human vision
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2982753/
https://www.ncbi.nlm.nih.gov/pubmed/20447413
http://dx.doi.org/10.1016/j.visres.2010.04.019
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