Characterizing And Predicting Growth In Reading Skills In Children With Developmental Dyslexia Through Functional Neuroimaging

Abstract

Children with developmental dyslexia exhibit deficits in a wide variety of reading skills that are attributable to underlying deficits in phonological processing. Functional neuroimaging studies show that these children exhibit differences in the activation of a distributed network of brain regions during reading tasks when compared to children without reading impairments. It is anticipated that children with dyslexia who are enrolled in a reading intervention will exhibit significant growth in reading skills over the course of their intervention. Furthermore, research has shown that activation of a distributed network of brain regions during reading tasks can be used to predict changes in children's reading skills over time. The present dissertation extends this research to a sample of children who completed a reading intervention. The specific goal of this dissertation is to predict children with dyslexia's growth in reading skills following a 2-year multisensory intervention through analyses of behavioral test scores and activation during two functional magnetic resonance imaging (fMRI) tasks completed prior to the intervention. Analyses suggested that the children in the present study exhibited significant growth in their reading skills. Initial measures of single word reading predicted growth in phonological decoding and reading comprehension. Furthermore, brain activation across both tasks was associated with growth in reading skills throughout the intervention. A general pattern emerged from the fMRI analyses such that negative correlations with growth in reading were more likely to occur in occipito-temporal regions and positive correlations with growth in reading were more likely to occur in prefrontal regions. These analyses help to further identify pre-intervention factors that may facilitate reading skill improvements in children with developmental dyslexia.