Neural pre-markers of dyslexia in children prior to reading onset: a longitudinal fMRI study
We seek to develop a comprehensive examination of the pre-reading brain to investigate the predictive value of neural pre-markers for DD and to characterize the developmental trajectories of functional and structural brain measures in children with and without a family history of DD. We will make these missing connections by examining 60 pre-readers with and 60 pre-readers without a family history of DD by following their reading development longitudinally from the pre-reading stage until third grade. Specifically, we will determine (1) If the functional brain differences that are associated with DD can already be observed prior to reading onset (Specific Aim 1); (2) If the structural brain differences that are associated with DD can already be observed prior to reading onset (Specific Aim 2); (3) How key reading skills (phonological processing, rapid auditory processing and reading fluency) develop as children move from being pre-readers to skilled readers (Specific Aim 3); and (4) which single predictor, or set of predictors, obtained from pre-readers and/or beginning readers will best predict reading outcome in children after three years of reading instruction (Specific Aim 4). Overall, the aim of the proposed study is to comprehensively characterize brain function and morphology in children with and without a family history of DD prior to the onset of reading and longitudinally follow these children’s brain development. Achieving this aim using functional and structural brain indices, as well as psychometric and psychophysical measures, will allow us to identify which marker or markers can be used to best predict later reading outcome. We will utilize a multi-level approach using functional and structural brain indices, and psychometric and psychophysical measures, which will allow us to identify which measures best predict later reading outcome. Assessments of brain function coupled with behavioral assessments of language and reading has been accomplished before in school-age children and adults with a diagnosis of DD but this will be the first study that will begin with young children before they receive formal schooling and follow them longitudinally through the early school years. This focus on an understudied age group (pre reader to beginning readers) within the DD population provides an important opportunity to develop predictors for an age group where intervention might be most effective. The contribution of our work to our understanding about the developmental trajectory of DD is increased by the potential impact on education practice and policy for early intervention in DD. The research is likely to provide important information on the trajectory of normal reading development. Additionally, it will likely draw increased research attention to this age group in DD and has the potential of providing a model for longitudinal studies of other developmental disabilities. Early identification of predictors for reading ability and disability in pre-reading children offers a chance to reduce the clinical, psychological and social implications of DD. Accumulating evidence reveals that early detection and intervention can ameliorate the worst effects of DD. Furthermore, predicting reading disability in pre-reading children is essential for the development and implementation of remediation programs. Early predictors will also help educators, scientists and parents find ways to support the academic and cognitive development of children with DD and may also lead to strategies that will reduce the severity of DD. A modified approach to the way we teach children how to read must involve the identification of children at risk and the development of early preventive strategies. The identification of a child with reading abilities in mid-elementary school is too late. By this stage, the delayed development of reading has already affected vocabulary skills and reading motivation. Children who are weak readers at the end of first grade remain poor readers by the end of elementary school. Therefore, improved early identification of children at risk may further lead to changes in educational policies. The ability to assign independent educational plans for children prior to reading onset will be essential for designing and implementing customized curriculums for children at-risk for reading disability.