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Disrupted segregation of working memory networks in temporal lobe epilepsy()

Working memory is a critical building block for almost all cognitive tasks, and impairment can cause significant disruption to daily life routines. We investigated the functional connectivity (FC) of the visuo-spatial working memory network in temporal lobe epilepsy and its relationship to the under...

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Autores principales: Stretton, J., Winston, G.P., Sidhu, M., Bonelli, S., Centeno, M., Vollmar, C., Cleary, R.A., Williams, E., Symms, M.R., Koepp, M.J., Thompson, P.J., Duncan, J.S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Elsevier 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777779/
https://www.ncbi.nlm.nih.gov/pubmed/24179782
http://dx.doi.org/10.1016/j.nicl.2013.01.009
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author Stretton, J.
Winston, G.P.
Sidhu, M.
Bonelli, S.
Centeno, M.
Vollmar, C.
Cleary, R.A.
Williams, E.
Symms, M.R.
Koepp, M.J.
Thompson, P.J.
Duncan, J.S.
author_facet Stretton, J.
Winston, G.P.
Sidhu, M.
Bonelli, S.
Centeno, M.
Vollmar, C.
Cleary, R.A.
Williams, E.
Symms, M.R.
Koepp, M.J.
Thompson, P.J.
Duncan, J.S.
author_sort Stretton, J.
collection PubMed
description Working memory is a critical building block for almost all cognitive tasks, and impairment can cause significant disruption to daily life routines. We investigated the functional connectivity (FC) of the visuo-spatial working memory network in temporal lobe epilepsy and its relationship to the underlying white matter tracts emanating from the hippocampus. Fifty-two patients with unilateral hippocampal sclerosis (HS) (30 left) and 30 healthy controls underwent working memory functional MRI (fMRI) and Diffusion Tensor Imaging (DTI). Six seed regions were identified for FC analysis; 4 within a task-positive network (left and right middle frontal gyri and superior parietal lobes), and 2 within a task-negative network (left and right hippocampi). FC maps were created by extracting the time-series of the fMRI signal in each region in each subject and were used as regressors of interest for additional GLM fMRI analyses. Structural connectivity (SC) corresponding to areas to which the left and right hippocampi were connected was determined using tractography, and a mean FA for each hippocampal SC map was calculated. Both left and right HS groups showed atypical FC between task-positive and task-negative networks compared to controls. This was characterised by co-activation of the task-positive superior parietal lobe ipsilateral to the typically task-negative sclerosed hippocampus. Correlational analysis revealed stronger FC between superior parietal lobe and ipsilateral hippocampus, was associated with worse performance in each patient group. The SC of the hippocampus was associated with the intra-hemispheric FC of the superior parietal lobe, in that greater SC was associated with weaker parieto-frontal FC. The findings suggest that the segregation of the task-positive and task-negative FC networks supporting working memory in TLE is disrupted, and is associated with abnormal structural connectivity of the sclerosed hippocampus. Co-activation of parieto-temporal regions was associated with poorer working memory and this may be associated with working memory dysfunction in TLE.
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spelling pubmed-37777792013-10-31 Disrupted segregation of working memory networks in temporal lobe epilepsy() Stretton, J. Winston, G.P. Sidhu, M. Bonelli, S. Centeno, M. Vollmar, C. Cleary, R.A. Williams, E. Symms, M.R. Koepp, M.J. Thompson, P.J. Duncan, J.S. Neuroimage Clin Article Working memory is a critical building block for almost all cognitive tasks, and impairment can cause significant disruption to daily life routines. We investigated the functional connectivity (FC) of the visuo-spatial working memory network in temporal lobe epilepsy and its relationship to the underlying white matter tracts emanating from the hippocampus. Fifty-two patients with unilateral hippocampal sclerosis (HS) (30 left) and 30 healthy controls underwent working memory functional MRI (fMRI) and Diffusion Tensor Imaging (DTI). Six seed regions were identified for FC analysis; 4 within a task-positive network (left and right middle frontal gyri and superior parietal lobes), and 2 within a task-negative network (left and right hippocampi). FC maps were created by extracting the time-series of the fMRI signal in each region in each subject and were used as regressors of interest for additional GLM fMRI analyses. Structural connectivity (SC) corresponding to areas to which the left and right hippocampi were connected was determined using tractography, and a mean FA for each hippocampal SC map was calculated. Both left and right HS groups showed atypical FC between task-positive and task-negative networks compared to controls. This was characterised by co-activation of the task-positive superior parietal lobe ipsilateral to the typically task-negative sclerosed hippocampus. Correlational analysis revealed stronger FC between superior parietal lobe and ipsilateral hippocampus, was associated with worse performance in each patient group. The SC of the hippocampus was associated with the intra-hemispheric FC of the superior parietal lobe, in that greater SC was associated with weaker parieto-frontal FC. The findings suggest that the segregation of the task-positive and task-negative FC networks supporting working memory in TLE is disrupted, and is associated with abnormal structural connectivity of the sclerosed hippocampus. Co-activation of parieto-temporal regions was associated with poorer working memory and this may be associated with working memory dysfunction in TLE. Elsevier 2013-02-01 /pmc/articles/PMC3777779/ /pubmed/24179782 http://dx.doi.org/10.1016/j.nicl.2013.01.009 Text en © 2013 The Authors http://creativecommons.org/licenses/by-nc-sa/3.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike License, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Article
Stretton, J.
Winston, G.P.
Sidhu, M.
Bonelli, S.
Centeno, M.
Vollmar, C.
Cleary, R.A.
Williams, E.
Symms, M.R.
Koepp, M.J.
Thompson, P.J.
Duncan, J.S.
Disrupted segregation of working memory networks in temporal lobe epilepsy()
title Disrupted segregation of working memory networks in temporal lobe epilepsy()
title_full Disrupted segregation of working memory networks in temporal lobe epilepsy()
title_fullStr Disrupted segregation of working memory networks in temporal lobe epilepsy()
title_full_unstemmed Disrupted segregation of working memory networks in temporal lobe epilepsy()
title_short Disrupted segregation of working memory networks in temporal lobe epilepsy()
title_sort disrupted segregation of working memory networks in temporal lobe epilepsy()
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777779/
https://www.ncbi.nlm.nih.gov/pubmed/24179782
http://dx.doi.org/10.1016/j.nicl.2013.01.009
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