Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions
Functional magnetic resonance imaging (fMRI) is a non-invasive technique that allows for visualization of activated brain regions. Until recently, fMRI studies have focused on gray matter. There are two main reasons white matter fMRI remains controversial: 1) the blood oxygen level dependent (BOLD)...
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doaj-936b1b12b3924a93becf2eea08f0267b2020-11-24T20:47:25ZengFrontiers Media S.A.Frontiers in Neuroscience1662-453X2014-08-01810.3389/fnins.2014.00239101955Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directionsJodie Reanna Gawryluk0Erin Lindsay Mazerolle1Ryan eD'Arcy2University of VictoriaUniversity of CalgarySimon Fraser UniversityFunctional magnetic resonance imaging (fMRI) is a non-invasive technique that allows for visualization of activated brain regions. Until recently, fMRI studies have focused on gray matter. There are two main reasons white matter fMRI remains controversial: 1) the blood oxygen level dependent (BOLD) fMRI signal depends on cerebral blood flow and volume, which are lower in white matter than gray matter and 2) fMRI signal has been associated with post-synaptic potentials (mainly localized in gray matter) as opposed to action potentials (the primary type of neural activity in white matter). Despite these observations, there is no direct evidence against measuring fMRI activation in white matter and reports of fMRI activation in white matter continue to increase. The questions underlying white matter fMRI activation are important. White matter fMRI activation has the potential to greatly expand the breadth of brain connectivity research, as well as improve the assessment and diagnosis of white matter and connectivity disorders. The current review provides an overview of the motivation to investigate white matter fMRI activation, as well as the published evidence of this phenomenon. We speculate on possible neurophysiologic bases of white matter fMRI signals, and discuss potential explanations for why reports of white matter fMRI activation are relatively scarce. We end with a discussion of future basic and clinical research directions in the study of white matter fMRI.http://journal.frontiersin.org/Journal/10.3389/fnins.2014.00239/fullCorpus CallosumInternal Capsulefunctional magnetic resonance imagingwhite matterbrain connectivity |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Jodie Reanna Gawryluk Erin Lindsay Mazerolle Ryan eD'Arcy |
spellingShingle |
Jodie Reanna Gawryluk Erin Lindsay Mazerolle Ryan eD'Arcy Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions Frontiers in Neuroscience Corpus Callosum Internal Capsule functional magnetic resonance imaging white matter brain connectivity |
author_facet |
Jodie Reanna Gawryluk Erin Lindsay Mazerolle Ryan eD'Arcy |
author_sort |
Jodie Reanna Gawryluk |
title |
Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions |
title_short |
Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions |
title_full |
Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions |
title_fullStr |
Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions |
title_full_unstemmed |
Does functional MRI detect activation in white matter?A review of emerging evidence, issues, and future directions |
title_sort |
does functional mri detect activation in white matter?a review of emerging evidence, issues, and future directions |
publisher |
Frontiers Media S.A. |
series |
Frontiers in Neuroscience |
issn |
1662-453X |
publishDate |
2014-08-01 |
description |
Functional magnetic resonance imaging (fMRI) is a non-invasive technique that allows for visualization of activated brain regions. Until recently, fMRI studies have focused on gray matter. There are two main reasons white matter fMRI remains controversial: 1) the blood oxygen level dependent (BOLD) fMRI signal depends on cerebral blood flow and volume, which are lower in white matter than gray matter and 2) fMRI signal has been associated with post-synaptic potentials (mainly localized in gray matter) as opposed to action potentials (the primary type of neural activity in white matter). Despite these observations, there is no direct evidence against measuring fMRI activation in white matter and reports of fMRI activation in white matter continue to increase. The questions underlying white matter fMRI activation are important. White matter fMRI activation has the potential to greatly expand the breadth of brain connectivity research, as well as improve the assessment and diagnosis of white matter and connectivity disorders. The current review provides an overview of the motivation to investigate white matter fMRI activation, as well as the published evidence of this phenomenon. We speculate on possible neurophysiologic bases of white matter fMRI signals, and discuss potential explanations for why reports of white matter fMRI activation are relatively scarce. We end with a discussion of future basic and clinical research directions in the study of white matter fMRI. |
topic |
Corpus Callosum Internal Capsule functional magnetic resonance imaging white matter brain connectivity |
url |
http://journal.frontiersin.org/Journal/10.3389/fnins.2014.00239/full |
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