Interrelations between neurocognitive, auditory, familial and environmental factors during early reading development

Reading skills are essential to participate in modern-day society. The acquisition of reading skills is a dynamic process involving several behavioral and neural processes that are influenced by genetic and environmental factors. Although this multifactorial etiology is widely recognized, the interplay between levels across reading development remains poorly understood. New insights in relations between the different levels across time can advance theoretical understanding of reading development. In turn, this can lead to improved support for struggling readers and diminished negative repercussions of reading difficulties on mental wellbeing and broader academic achievement. With the current dissertation, we aimed to contribute to the field by extending our knowledge of some of the possible interrelations between behavioral, neural, familial and environmental factors across early reading development. A total of 162 Dutch-speaking children, of whom the majority had an increased family and/or cognitive risk for reading difficulties, were followed up from the pre-reading stage (kindergarten) until third grade. We showed that auditory and speech processing as well as auditory cortex structure in the pre-reading stage can predict later reading outcome, independent of familial risk for reading difficulties. When examined simultaneously with phonological processing though, speech processing showed a cascading effect on phonological awareness and consequently on reading. In light of the COVID-19 pandemic, we also looked at the influence of a critical change in the environment (school closures) on the development of phonological awareness and white matter plasticity in the reading network. Although unexpected, we did not find evidence for a negative impact of the school closures. We did, however, find a scanner-related difference in white matter integrity, which provides a cautionary tale for researchers wanting to set up much-needed neuroimaging collaborations. Although generalization to the population as a whole is limited, the findings of this dissertation have contributed to the theoretical understanding of reading development. Increasing understanding further will be pivotal to fine-tune identification and intervention strategies for struggling readers and to improve individual and societal outcomes.