Poster D71, Wednesday, August 21, 2019, 5:15 – 7:00 pm, Restaurant Hall
Changes in resting-state functional brain connectivity and reading ability following reading intervention
Alexandra Cross1, Christine L. Stager2, Karen A. Steinbach3, Maureen W. Lovett3, Jan C. Frijters4, Lisa M.D. Archibald1, Marc F. Joanisse1;1University of Western Ontario, 2Thames Valley District School Board, 3The Hospital for Sick Children, 4Brock University
Past studies of adults and children have demonstrated changes in the structure and function of the brain following reading intervention. However, neuroimaging studies examining effects of reading intervention have relied on explicit reading tasks, making it difficult to determine whether brain differences are due to differences in task-based performance or in the underlying neural organization supporting reading. Here we use resting-state fMRI to measure inter-regional correlations of spontaneous fluctuations in neural activity in children with reading disability (dyslexia). Using a longitudinal design, we examine the significant variability in the degree to which poor readers benefit from explicit reading intervention. This permits us to better understand neural correlates of response to intervention. Participants were children aged 8 to 12 years who have been identified with reading disability and enrolled in a 110-hour small-group intervention for struggling readers (Empower Reading). The intervention has been previously shown to result in significant and generalizable gains in decoding, word recognition, reading accuracy, reading rate, and reading comprehension. Prior to beginning the reading program, children completed standardized and laboratory-developed measures of reading subskills. They next participated in two resting-state fMRI sessions, spaced nine months apart and corresponding to starting and completing the Empower program. The behavioural measures of reading were also administered following the Empower program. Analyses examined how changes in connectivity within the brain’s functional reading network were related to behavioural changes in reading ability pre- and post-intervention. Changes in behavioural reading ability were positively associated with increased resting-state functional connectivity within both left hemisphere and right hemisphere nodes making up the classical reading network. Interestingly, changes in reading ability were negatively associated with changes in functional connectivity between hemispheres. Specifically, this included changes in connectivity between the right inferior frontal gyrus and left hemisphere areas including left inferior frontal gyrus, left intraparietal sulcus, and left thalamus, as well as changes in connectivity between the right intraparietal sulcus and the left thalamus, and between the right superior temporal gyrus and the left intraparietal sulcus. These results confirm that intrinsic functional networks of the brain are changed as a result of reading intervention, and suggest that growth in reading skills is related to both increased functional connectivity within the left hemisphere and reduced inter-hemispheric connectivity. We also comment on how we might use connectivity patterns prior to intervention to identify individual differences in subsequent response to intervention.
Themes: Reading, Disorders: Developmental
Method: Functional Imaging