TY - JOUR
T1 - Low-frequency signal changes reflect differences in functional connectivity between good readers and dyslexics during continuous phoneme mapping
AU - Stanberry, Larissa I.
AU - Richards, Todd L.
AU - Berninger, Virginia W.
AU - Nandy, Rajesh R.
AU - Aylward, Elizabeth H.
AU - Maravilla, Kenneth R.
AU - Stock, Patricia S.
AU - Cordes, Dietmar
N1 - Funding Information:
The authors thank Dr. Victor Haughton (University of Wisconsin–Madison) and Dr. Susan Bookheimer (UCLA) for their valuable suggestions. The authors thank the anonymous reviewers for their excellent comments which helped to improve the manuscript. They also acknowledge helpful discussions with Dr. Mark Eckert at Stanford University. This research was supported by a special multidisciplinary center grant P50-33812 from the National Institute of Child Health and Human Development (NICHD).
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006/4
Y1 - 2006/4
N2 - The current fMRI study investigated correlations of low-frequency signal changes in the left inferior frontal gyrus, right inferior frontal gyrus and cerebellum in 13 adult dyslexic and 10 normal readers to examine functional networks associated with these regions. The extent of these networks to regions associated with phonological processing (frontal gyrus, occipital gyrus, angular gyrus, inferior temporal gyrus, fusiform gyrus, supramarginal gyrus and cerebellum) was compared between good and dyslexic readers. Analysis of correlations in low-frequency range showed that regions known to activate during an "on-off" phoneme-mapping task exhibit synchronous signal changes when the task is administered continuously (without any "off" periods). Results showed that three functional networks, which were defined on the basis of documented structural deficits in dyslexics and included regions associated with phonological processing, differed significantly in spatial extent between good readers and dyslexics. The methodological, theoretical and clinical significance of the findings for advancing fMRI research and knowledge of dyslexia are discussed.
AB - The current fMRI study investigated correlations of low-frequency signal changes in the left inferior frontal gyrus, right inferior frontal gyrus and cerebellum in 13 adult dyslexic and 10 normal readers to examine functional networks associated with these regions. The extent of these networks to regions associated with phonological processing (frontal gyrus, occipital gyrus, angular gyrus, inferior temporal gyrus, fusiform gyrus, supramarginal gyrus and cerebellum) was compared between good and dyslexic readers. Analysis of correlations in low-frequency range showed that regions known to activate during an "on-off" phoneme-mapping task exhibit synchronous signal changes when the task is administered continuously (without any "off" periods). Results showed that three functional networks, which were defined on the basis of documented structural deficits in dyslexics and included regions associated with phonological processing, differed significantly in spatial extent between good readers and dyslexics. The methodological, theoretical and clinical significance of the findings for advancing fMRI research and knowledge of dyslexia are discussed.
KW - Cerebellum
KW - Clustering
KW - Continuous task
KW - Dyslexia
KW - Functional connectivity
KW - Inferior frontal gyrus
KW - Phoneme mapping
KW - Sharpening
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U2 - 10.1016/j.mri.2005.12.006
DO - 10.1016/j.mri.2005.12.006
M3 - Article
C2 - 16563950
AN - SCOPUS:33645046667
SN - 0730-725X
VL - 24
SP - 217
EP - 229
JO - Magnetic Resonance Imaging
JF - Magnetic Resonance Imaging
IS - 3
ER -