Cargando…

Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size

Studies of the hippocampus use smaller voxel sizes and smoothing kernels than cortical activation studies, typically using a multivoxel seed with specified radius for connectivity analysis. This study identified optimal processing parameters for evaluating hippocampal connectivity with sensorimotor...

Descripción completa

Detalles Bibliográficos
Autor principal: Burman, Douglas D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8651104/
https://www.ncbi.nlm.nih.gov/pubmed/34874961
http://dx.doi.org/10.1371/journal.pone.0260245
_version_ 1784611339835015168
author Burman, Douglas D.
author_facet Burman, Douglas D.
author_sort Burman, Douglas D.
collection PubMed
description Studies of the hippocampus use smaller voxel sizes and smoothing kernels than cortical activation studies, typically using a multivoxel seed with specified radius for connectivity analysis. This study identified optimal processing parameters for evaluating hippocampal connectivity with sensorimotor cortex (SMC), comparing effectiveness by varying parameters during both activation and connectivity analysis. Using both 3mm and 4mm isovoxels, smoothing kernels of 0-10mm were evaluated on the amplitude and extent of motor activation and hippocampal connectivity with SMC. Psychophysiological interactions (PPI) identified hippocampal connectivity with SMC during volitional movements, and connectivity effects from multivoxel seeds were compared with alternate methods; a structural seed represented the mean connectivity map from all voxels within a region, whereas a functional seed represented the regional voxel with maximal SMC connectivity. With few exceptions, the same parameters were optimal for activation and connectivity. Larger isovoxels showed larger activation volumes in both SMC and the hippocampus; connectivity volumes from structural seeds were also larger, except from the posterior hippocampus. Regardless of voxel size, the 10mm smoothing kernel generated larger activation and connectivity volumes from structural seeds, as well as larger beta estimates at connectivity maxima; structural seeds also produced larger connectivity volumes than multivoxel seeds. Functional seeds showed lesser effects from voxel size and smoothing kernels. Optimal parameters revealed topography in structural seed connectivity along both the longitudinal axis and mediolateral axis of the hippocampus. These results indicate larger voxels and smoothing kernels can improve sensitivity for detecting both cortical activation and hippocampal connectivity.
format Online
Article
Text
id pubmed-8651104
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-86511042021-12-08 Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size Burman, Douglas D. PLoS One Research Article Studies of the hippocampus use smaller voxel sizes and smoothing kernels than cortical activation studies, typically using a multivoxel seed with specified radius for connectivity analysis. This study identified optimal processing parameters for evaluating hippocampal connectivity with sensorimotor cortex (SMC), comparing effectiveness by varying parameters during both activation and connectivity analysis. Using both 3mm and 4mm isovoxels, smoothing kernels of 0-10mm were evaluated on the amplitude and extent of motor activation and hippocampal connectivity with SMC. Psychophysiological interactions (PPI) identified hippocampal connectivity with SMC during volitional movements, and connectivity effects from multivoxel seeds were compared with alternate methods; a structural seed represented the mean connectivity map from all voxels within a region, whereas a functional seed represented the regional voxel with maximal SMC connectivity. With few exceptions, the same parameters were optimal for activation and connectivity. Larger isovoxels showed larger activation volumes in both SMC and the hippocampus; connectivity volumes from structural seeds were also larger, except from the posterior hippocampus. Regardless of voxel size, the 10mm smoothing kernel generated larger activation and connectivity volumes from structural seeds, as well as larger beta estimates at connectivity maxima; structural seeds also produced larger connectivity volumes than multivoxel seeds. Functional seeds showed lesser effects from voxel size and smoothing kernels. Optimal parameters revealed topography in structural seed connectivity along both the longitudinal axis and mediolateral axis of the hippocampus. These results indicate larger voxels and smoothing kernels can improve sensitivity for detecting both cortical activation and hippocampal connectivity. Public Library of Science 2021-12-07 /pmc/articles/PMC8651104/ /pubmed/34874961 http://dx.doi.org/10.1371/journal.pone.0260245 Text en © 2021 Douglas D. Burman https://creativecommons.org/licenses/by/4.0/This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Burman, Douglas D.
Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
title Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
title_full Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
title_fullStr Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
title_full_unstemmed Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
title_short Topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
title_sort topography of hippocampal connectivity with sensorimotor cortex revealed by optimizing smoothing kernel and voxel size
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8651104/
https://www.ncbi.nlm.nih.gov/pubmed/34874961
http://dx.doi.org/10.1371/journal.pone.0260245
work_keys_str_mv AT burmandouglasd topographyofhippocampalconnectivitywithsensorimotorcortexrevealedbyoptimizingsmoothingkernelandvoxelsize