TY - JOUR
T1 - No evidence for systematic white matter correlates of dyslexia
T2 - An Activation Likelihood Estimation meta-analysis
AU - Moreau, David
AU - Stonyer, Josephine E.
AU - McKay, Nicole S.
AU - Waldie, Karen E.
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/3/15
Y1 - 2018/3/15
N2 - Dyslexia is a prevalent neurodevelopmental disorder, characterized by reading and spelling difficulties. Beyond the behavioral and functional correlates of this condition, a growing number of studies have explored structural differences between individuals with dyslexia and typically developing individuals. To date, findings remain disparate – some studies suggest differences in fractional anisotropy (FA), an indirect measure of white matter integrity, whereas others do not identify significant disparities. Here, we synthesized the existing literature on this topic by conducting a meta-analysis of Diffusion Tensor Imaging (DTI) studies investigating white matter correlates of dyslexia via voxel-based analyses (VBA) of FA. Our results showed no reliable clusters underlying differences between dyslexics and typical individuals, after correcting for multiple comparisons (false discovery rate correction). Because group comparisons might be too coarse to yield subtle differences, we further explored differences in FA as a function of reading ability, measured on a continuous scale. Consistent with our initial findings, reading ability was not associated with reliable differences in white matter integrity. These findings nuance the current view of profound, structural differences underlying reading ability and its associated disorders, and suggest that their neural correlates might be more subtle than previously thought.
AB - Dyslexia is a prevalent neurodevelopmental disorder, characterized by reading and spelling difficulties. Beyond the behavioral and functional correlates of this condition, a growing number of studies have explored structural differences between individuals with dyslexia and typically developing individuals. To date, findings remain disparate – some studies suggest differences in fractional anisotropy (FA), an indirect measure of white matter integrity, whereas others do not identify significant disparities. Here, we synthesized the existing literature on this topic by conducting a meta-analysis of Diffusion Tensor Imaging (DTI) studies investigating white matter correlates of dyslexia via voxel-based analyses (VBA) of FA. Our results showed no reliable clusters underlying differences between dyslexics and typical individuals, after correcting for multiple comparisons (false discovery rate correction). Because group comparisons might be too coarse to yield subtle differences, we further explored differences in FA as a function of reading ability, measured on a continuous scale. Consistent with our initial findings, reading ability was not associated with reliable differences in white matter integrity. These findings nuance the current view of profound, structural differences underlying reading ability and its associated disorders, and suggest that their neural correlates might be more subtle than previously thought.
KW - Axonal white matter
KW - Diffusion tensor imaging
KW - Dyslexia
KW - Fractional anisotropy
KW - Neurodevelopmental disorders
KW - Voxel-based analyses
UR - http://www.scopus.com/inward/record.url?scp=85041427279&partnerID=8YFLogxK
U2 - 10.1016/j.brainres.2018.01.014
DO - 10.1016/j.brainres.2018.01.014
M3 - Article
C2 - 29456133
AN - SCOPUS:85041427279
SN - 0006-8993
VL - 1683
SP - 36
EP - 47
JO - Brain Research
JF - Brain Research
ER -