Open AccessWhen all hypotheses are right: A multifocal account of dyslexia
Author(s) -
Pernet Cyril,
Andersson Jesper,
Paulesu Eraldo,
Demonet Jean Francois
Publication year - 2009
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.20670
Subject(s) - dyslexia , psychology , lateralization of brain function , hum , laterality , cognitive psychology , spelling , reading (process) , audiology , neuroscience , medicine , linguistics , philosophy , art , performance art , art history
Abstract Many hypotheses have been proposed about the brain underpinnings of developmental dyslexia, but none of them accommodates the variable deficits observed. To address the issue of anatomical deficits in dyslexia; total and partial volumes, lateralization indices (LI), and local gray matter volumes (LGMV) were measured. Analyses were performed in large samples of control and dyslexic subjects, and in correlation with their performance on phonological, reading, and spelling tests. Results indicate an absence of net differences in terms of volumes but significant continuities and discontinuities between groups in their correlations between LI, LGMV, and performances. Structural connectivity also highlighted correlations between areas showing (dis)continuities between control and dyslexic subjects. Overall, our data put forward the idea of a multifocal brain abnormalities in dyslexia with a major implication of the left superior temporal gyrus, occipital‐temporal cortices, and lateral/medial cerebellum, which could account for the diverse deficits predicted by the different theories. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc.