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Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise

The observation of highly variable sets of association neocortical areas across individuals, containing the estimated generators of Slow Potentials (SPs) and beta oscillations, lead to the persistence in individual analyses. This brought to notice an unexpected within individual topographic similari...

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Autores principales: Basile, Luis F. H., Sato, João R., Pasquini, Henrique A., Lozano, Mirna D., Nucci, Mariana P., Velasques, Bruna, Ribeiro, Pedro, Ramos, Renato T., Anghina, Renato
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4444270/
https://www.ncbi.nlm.nih.gov/pubmed/26010428
http://dx.doi.org/10.1371/journal.pone.0128343
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author Basile, Luis F. H.
Sato, João R.
Pasquini, Henrique A.
Lozano, Mirna D.
Nucci, Mariana P.
Velasques, Bruna
Ribeiro, Pedro
Ramos, Renato T.
Anghina, Renato
author_facet Basile, Luis F. H.
Sato, João R.
Pasquini, Henrique A.
Lozano, Mirna D.
Nucci, Mariana P.
Velasques, Bruna
Ribeiro, Pedro
Ramos, Renato T.
Anghina, Renato
author_sort Basile, Luis F. H.
collection PubMed
description The observation of highly variable sets of association neocortical areas across individuals, containing the estimated generators of Slow Potentials (SPs) and beta oscillations, lead to the persistence in individual analyses. This brought to notice an unexpected within individual topographic similarity between task conditions, despite our original interest in task-related differences. A recent related work explored the quantification of the similarity in beta topography between largely differing tasks. In this article, we used Independent Component Analysis (ICA) for the decomposition of beta activity from a visual attention task, and compared it with quiet resting, recorded by 128-channel EEG in 62 subjects. We statistically tested whether each ICA component obtained in one condition could be explained by a linear regression model based on the topographic patterns from the other condition, in each individual. Results were coherent with the previous report, showing a high topographic similarity between conditions. From an average of 12 beta component maps obtained for each task, over 80% were satisfactorily explained by the complementary task. Once more, the component maps including those considered unexplained, putatively “task-specific”, had their scalp distribution and estimated cortical sources highly variable across subjects. These findings are discussed along with other studies based on individual data and the present fMRI results, reinforcing the increasingly accepted view that individual variability in sets of active neocortical association areas is not noise, but intrinsic to cortical physiology. Actual ‘noise’, mainly stemming from group “brain averaging” and the emphasis on statistical differences as opposed to similarities, may explain the overall hardship in replication of the vast literature on supposed task-specific forms of activity, and the ever inconclusive status of a universal functional mapping of cortical association areas. A new hypothesis, that individuals may use the same idiosyncratic sets of areas, at least by their fraction of activity in the sub-delta and beta range, in various non-sensory-motor forms of conscious activities, is a corollary of the discussed variability.
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spelling pubmed-44442702015-06-16 Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise Basile, Luis F. H. Sato, João R. Pasquini, Henrique A. Lozano, Mirna D. Nucci, Mariana P. Velasques, Bruna Ribeiro, Pedro Ramos, Renato T. Anghina, Renato PLoS One Research Article The observation of highly variable sets of association neocortical areas across individuals, containing the estimated generators of Slow Potentials (SPs) and beta oscillations, lead to the persistence in individual analyses. This brought to notice an unexpected within individual topographic similarity between task conditions, despite our original interest in task-related differences. A recent related work explored the quantification of the similarity in beta topography between largely differing tasks. In this article, we used Independent Component Analysis (ICA) for the decomposition of beta activity from a visual attention task, and compared it with quiet resting, recorded by 128-channel EEG in 62 subjects. We statistically tested whether each ICA component obtained in one condition could be explained by a linear regression model based on the topographic patterns from the other condition, in each individual. Results were coherent with the previous report, showing a high topographic similarity between conditions. From an average of 12 beta component maps obtained for each task, over 80% were satisfactorily explained by the complementary task. Once more, the component maps including those considered unexplained, putatively “task-specific”, had their scalp distribution and estimated cortical sources highly variable across subjects. These findings are discussed along with other studies based on individual data and the present fMRI results, reinforcing the increasingly accepted view that individual variability in sets of active neocortical association areas is not noise, but intrinsic to cortical physiology. Actual ‘noise’, mainly stemming from group “brain averaging” and the emphasis on statistical differences as opposed to similarities, may explain the overall hardship in replication of the vast literature on supposed task-specific forms of activity, and the ever inconclusive status of a universal functional mapping of cortical association areas. A new hypothesis, that individuals may use the same idiosyncratic sets of areas, at least by their fraction of activity in the sub-delta and beta range, in various non-sensory-motor forms of conscious activities, is a corollary of the discussed variability. Public Library of Science 2015-05-26 /pmc/articles/PMC4444270/ /pubmed/26010428 http://dx.doi.org/10.1371/journal.pone.0128343 Text en © 2015 Basile et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Basile, Luis F. H.
Sato, João R.
Pasquini, Henrique A.
Lozano, Mirna D.
Nucci, Mariana P.
Velasques, Bruna
Ribeiro, Pedro
Ramos, Renato T.
Anghina, Renato
Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise
title Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise
title_full Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise
title_fullStr Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise
title_full_unstemmed Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise
title_short Individual Topographic Variability Is Inherent to Cortical Physiology but Task-Related Differences May Be Noise
title_sort individual topographic variability is inherent to cortical physiology but task-related differences may be noise
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4444270/
https://www.ncbi.nlm.nih.gov/pubmed/26010428
http://dx.doi.org/10.1371/journal.pone.0128343
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