Schedule of Events | Symposia

Examining associations between white matter microstructure in infancy and subsequent reading comprehension skills: A longitudinal investigation

Poster Session E - Monday, March 31, 2025, 2:30 – 4:30 pm EDT, Back Bay Ballroom/Republic Ballroom

Megan Loh¹, Ted Turesky¹, Olivia Baldi¹, Emily Hu¹, Nadine Gaab¹; ¹Harvard Graduate School of Education

Reading comprehension (RC) is a complex skill essential for functioning in modern society. Early reading models posit that RC requires word recognition (WR) and language comprehension (LC) skills but also emphasize reading fluency (RF) as a key factor for developing RC. The left-hemispheric arcuate fasciculus (AF) and inferior longitudinal fasciculus (ILF) are important white matter tracts linked with WR and RC in school-age children. Furthermore, fractional anisotropy (FA) of the left AF in infants has been linked to oral language skills in preschool, suggesting the emergence of a scaffold for reading development as early as infancy. We investigated whether FA in the AF and ILF in infancy is also related to subsequent RF and RC skills. Diffusion tensor imaging data were acquired in 31 infants, who had reading skills assessed nine years later at school-age. Whole-brain tractography was performed with MRtrix3 and fibers were segmented into canonical tracts, each 100 nodes, using pyBabyAFQ. Results showed that FA in infancy is positively associated with subsequent higher-order reading skills, specifically between; the left AF and RC, as well as between the left ILF and RF and RC. These results remained significant when controlling for age at time of scan, biological sex, and home literacy environments. These results highlight the role of the left AF and ILF in supporting the long-term development of RF and RC starting as early as infancy. Further analyses are necessary to understand the specific WR and LC mechanisms that connect early white matter organization and higher-order reading skills.

Topic Area: LANGUAGE: Development & aging