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Visual representations are dominated by intrinsic fluctuations correlated between areas
Intrinsic cortical dynamics are thought to underlie trial-to-trial variability of visually evoked responses in animal models. Understanding their function in the context of sensory processing and representation is a major current challenge. Here we report that intrinsic cortical dynamics strongly af...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Academic Press
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4503804/ https://www.ncbi.nlm.nih.gov/pubmed/25896934 http://dx.doi.org/10.1016/j.neuroimage.2015.04.026 |
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author | Henriksson, Linda Khaligh-Razavi, Seyed-Mahdi Kay, Kendrick Kriegeskorte, Nikolaus |
author_facet | Henriksson, Linda Khaligh-Razavi, Seyed-Mahdi Kay, Kendrick Kriegeskorte, Nikolaus |
author_sort | Henriksson, Linda |
collection | PubMed |
description | Intrinsic cortical dynamics are thought to underlie trial-to-trial variability of visually evoked responses in animal models. Understanding their function in the context of sensory processing and representation is a major current challenge. Here we report that intrinsic cortical dynamics strongly affect the representational geometry of a brain region, as reflected in response-pattern dissimilarities, and exaggerate the similarity of representations between brain regions. We characterized the representations in several human visual areas by representational dissimilarity matrices (RDMs) constructed from fMRI response-patterns for natural image stimuli. The RDMs of different visual areas were highly similar when the response-patterns were estimated on the basis of the same trials (sharing intrinsic cortical dynamics), and quite distinct when patterns were estimated on the basis of separate trials (sharing only the stimulus-driven component). We show that the greater similarity of the representational geometries can be explained by coherent fluctuations of regional-mean activation within visual cortex, reflecting intrinsic dynamics. Using separate trials to study stimulus-driven representations revealed clearer distinctions between the representational geometries: a Gabor wavelet pyramid model explained representational geometry in visual areas V1–3 and a categorical animate–inanimate model in the object-responsive lateral occipital cortex. |
format | Online Article Text |
id | pubmed-4503804 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Academic Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-45038042015-07-21 Visual representations are dominated by intrinsic fluctuations correlated between areas Henriksson, Linda Khaligh-Razavi, Seyed-Mahdi Kay, Kendrick Kriegeskorte, Nikolaus Neuroimage Article Intrinsic cortical dynamics are thought to underlie trial-to-trial variability of visually evoked responses in animal models. Understanding their function in the context of sensory processing and representation is a major current challenge. Here we report that intrinsic cortical dynamics strongly affect the representational geometry of a brain region, as reflected in response-pattern dissimilarities, and exaggerate the similarity of representations between brain regions. We characterized the representations in several human visual areas by representational dissimilarity matrices (RDMs) constructed from fMRI response-patterns for natural image stimuli. The RDMs of different visual areas were highly similar when the response-patterns were estimated on the basis of the same trials (sharing intrinsic cortical dynamics), and quite distinct when patterns were estimated on the basis of separate trials (sharing only the stimulus-driven component). We show that the greater similarity of the representational geometries can be explained by coherent fluctuations of regional-mean activation within visual cortex, reflecting intrinsic dynamics. Using separate trials to study stimulus-driven representations revealed clearer distinctions between the representational geometries: a Gabor wavelet pyramid model explained representational geometry in visual areas V1–3 and a categorical animate–inanimate model in the object-responsive lateral occipital cortex. Academic Press 2015-07-01 /pmc/articles/PMC4503804/ /pubmed/25896934 http://dx.doi.org/10.1016/j.neuroimage.2015.04.026 Text en © 2015 The Authors. Published by Elsevier Inc. http://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). |
spellingShingle | Article Henriksson, Linda Khaligh-Razavi, Seyed-Mahdi Kay, Kendrick Kriegeskorte, Nikolaus Visual representations are dominated by intrinsic fluctuations correlated between areas |
title | Visual representations are dominated by intrinsic fluctuations correlated between areas |
title_full | Visual representations are dominated by intrinsic fluctuations correlated between areas |
title_fullStr | Visual representations are dominated by intrinsic fluctuations correlated between areas |
title_full_unstemmed | Visual representations are dominated by intrinsic fluctuations correlated between areas |
title_short | Visual representations are dominated by intrinsic fluctuations correlated between areas |
title_sort | visual representations are dominated by intrinsic fluctuations correlated between areas |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4503804/ https://www.ncbi.nlm.nih.gov/pubmed/25896934 http://dx.doi.org/10.1016/j.neuroimage.2015.04.026 |
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