Brain structures associated with reading and their abnormalities in dyslexia: a wholebrain analysis [article]

Teija Kujala, Anja Thiede, Peter Palo-oja, Paula Virtala, Marja Laasonen, Jussi Numminen, Aleksi J Sihvonen
2020 bioRxiv   pre-print
Developmental dyslexia (DD) is a highly prevalent neurodevelopmental disorder, which is devastating for individuals in modern societies in which fluent reading skill is mandatory for leading a normal life. Research on the neural origins of DD has continued for half a century, yielding, however, inconsistent results. It has also lacked a thorough characterization of the association between abnormal neuroanatomy and skills vital for reading. The current study was set out to determine
more » ... of grey and white matter volumes in adults with DD and associations between brain structures and reading and related skills. To this end, we conducted a whole-brain voxel based morphometry following current guidelines on state-of-the-art analysis approaches and rigorous neuropsychological testing. We found decreased volumes of grey matter in DD, comprising a left-hemispheric network including superior temporal and inferior frontal gyri, insula, the limbic system, and basal ganglia, and white matter, including the right middle temporal gyrus and hippocampus. These results are both consistent with the most robust previous findings on structural abnormalities in the left frontotemporal network in DD and yield novel insight to the role of subcortical structures in DD, scarcely studied so far. Moreover, areas with decreased grey matter volumes in DD were positively associated with technical reading scores (both groups included). This provides particularly strong support for the conclusion that the grey matter regions that we identified to have a low volume in DD comprise the core areas vital for reading.
doi:10.1101/2020.03.27.011577 fatcat:bl7i6xy4qbhrfmmxjnrt33pooe