The brain is incredibly good at adapting to adversity and overcoming deficits. Human neural imaging techniques show us a variety of different metrics of neural firing, including magnetic field shifts (MEG), scalp potentials (EEG/ERP), and blood oxygen levels (fMRI), but which of these can actually help us explain behavior? This branch of my program aims to look for neural correlates of behavior in children with dyslexia throughout development, as a function of the disorder, and as predictors of intervention success.
A main goal of my research is to improve our knowledge of neural and genetic mechanisms so we can improve early diagnosis methods for dyslexia. In collaboration with several individuals in my postdoctoral lab, we evaluated the specialization of a brain region involved in visual word processing (the visual word form area/VWFA) in typically reading children and adults using fMRI. We found that in children and adults, the VWFA is sensitive to print when compared to non-linguistic stimuli like faces or visual noise. However, only adults have specificity for print, when compared to nameable object drawings.
- TM Centanni, LW King MD Eddy,S Whitfield-Gabrieli, JDE Gabrieli (in press). Development of Sensitivity versus Specificity for Print in the Visual Word Form Area. Brain and Language.
Further, we see that in young children, who have not yet received formal reading instruction, the degree of letter specific responses in the brain is correlated with number of words a child can read correctly. Importantly, a child's family history of reading disability and that child's inherent risk for developing a reading disorder like dyslexia, may be related to the development of the reading network, and ongoing analyses are focused on addressing this question. These two studies together suggest a long and intricate developmental trajectory for the VWFA and provide a baseline for evaluating the development of the VWFA in dyslexia.
- TM Centanni, ES Norton, A Park, SD Beach, K Halverson, N Gaab, JDE Gabrieli. Letter Selectivity in Left Fusiform Gyrus Predicts Letter Knowledge and Word Reading in Kindergarten Children. Manuscript under review.