Altered Cortico-Cerebellar Effective Connectivity of the Visuo-Attention System is associated with READ1 deletion in Developmental Dyslexia

Motivation: Aberrant brain functional activation was observed in developmental dyslexia (DD). However, how genetic vulnerability and reading proficiency impact on specific cortico-cerebellar interactions remains unknown. Goal(s): We investigated how visuo-attentional processing is associated with reading proficiency and genetic vulnerability in DD to understand task-dependent differences in brain connectivity. Approach: Dynamic Causal Modelling with Parametric Empirical Bayes links individuals' neuronal connection strength to their behavioural measures to characterise aberrant network structures. Results: Children with DD showed distinctive causal connectivity patterns between the cerebellum and visuo-attentional regions. Particularly, the combination of DD and genetic vulnerability showed remarkable differences in excitation-inhibition dynamics. Impact: Our approach of combining imaging with genetics demonstrates that effective connectivity between cortico-cerebellar regions involved in attention is essential for reading ability and that genetic alterations impact on the excitatory strength of such connections, providing possible targets for neuro-modulatory interventions.