Phonological Deficit and its Brain Correlates in Children with Developmental Dyslexia

Abstract

This work is a comprehensive cross-methodological experimental study of phonological processing disorders in dyslexic Russian-speaking children. We developed and standardized a Russian-language test battery to assess phonological processing skills (The Russian Test of Phonological Processing), wich we then used to assess the features of phonological deficits in children with dyslexia and conduct an analysis of reading difficulties and their structural brain correlates using modern methods of videooculography and neuroimaging. The first phase’s findings revealed that more complex phonological tests were also more difficult, whereas children’s performance in these tests was found to be a significant predictor of reading speed. The project’s second phase identified five common patterns of eye movements during reading in children with and without dyslexia. We discovered that children with dyslexia exhibit the same patterns as their typically developing peers, albeit with a three-year delay. Finally, the third phase revealed significant differences in gray matter volume in the cerebellum, insula, and parietal lobule between group of children with dyslexia and control group of typically developing children. These findings have significant implications for clinical practice, interdisciplinary research on dyslexia, and possibly the educational system.