The influence of intergenerational transfer of white matter tracts on early reading development

Parents have large genetic and environmental influences on their childrens cognition, behavior, and brain. Previous studies have indicated intergenerational transfer of the behavior of reading. Despite a close coupling between brain and behavior however, the intergenerational transfer of reading-related structural brain networks have not been investigated. Therefore, we investigated its parent-child associations for the first time. We examined how white matter tracts i.e., Arcuate Fasciculus (AF) and Inferior Fronto-Occipital Fasciculus (IFOF), are associated with childrens early reading development from Kindergarten to Grade 3 in 33 families. First, we observed in our sample of children -who all had typical reading skills despite half of them having an increased risk for dyslexia- that fractional anisotropy in bilateral IFOF and right AF correlated with reading development. Second, parent-child correlations were observed for bilateral IFOF but not for AF. Finally, we demonstrated that the relation between childrens IFOF and reading development was largely explained by parental IFOF. The findings preliminarily suggest that white matter organization in IFOF represents a pre-existing protective factor in children at risk, as it is mainly determined by biological parental factors. Large-scale intergenerational, multi-level and longitudinal studies are needed to understand the dynamic interrelations between brain, environment and behavior.