Elucidating the role of experience in the functional neural specialization for reading

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As children learn to read, brain regions associated with visual and language processing form specialized cortical circuits involving predominantly left-hemisphere occipitotemporal, temporoparietal, and frontal regions-the brain's `reading network'. Reading experience drives the functional neural specialization for visual word processing. To date, the critical role of experience in functional neural specialization has remained unexamined because most research has only examined neurodevelopmental trajectories for reading in children with reading experience-children who begin formal literacy instruction when they enroll in school at a government-mandated age (6 years). Our existing approaches to studying the emergence of reading function in the brain cannot separate the discrete effects of experience and age. An important theoretical advance would be to test how the brain's reading network forms through reading experience or lack thereof across development. The resettlement of refugee children provides an opportunity to address these outstanding issues. For refugee children, displacement and migration often corresponds to a period of interrupted schooling and limited reading experience. As refugee children of different ages resettle in Canada, they learn a new language and learn to read at school. Individual differences in language and reading experiences among refugee children provide a `natural paradigm' from which we can test specific hypotheses concerning the role of experience in functional neural specialization for visual word processing. The proposed research program leverages the latest tools of developmental cognitive neuroscience (functional neuroimaging) to examine the emergence of neural systems for visual word processing in children who have experienced variable periods of interrupted schooling and resumed schooling/learning to read at different ages. We aim to examine the neural bases for language and visual word processing in Syrian refugee children who've experienced interrupted schooling and recently resettled in Canada, and other newcomer children who've experienced continuous schooling. Second, we aim to examine longitudinal changes in neural activation and functional connectivity for phonological, lexical-semantic, and visual word processing as a function of age of reading experience, and examine how longitudinal neural changes correspond to children's reading skills over time. To do so, we track neural activation and functional connectivity for language and visual word processing in Afghan refugee children who've experienced interrupted schooling and who will arrive in Canada over the next two years. Examining the role of experience in the functional neural specialization for reading will provide important theoretical and practical insights-we gain a deeper understanding of the development of neural systems across diverse developmental experiences, and the changing plasticity of neural systems across development.