Dyslexia: The role of the cerebellum

Introduction: In this review article we outline the thinking and evidence behind our hypothe-sis that the problems suffered by dyslexic people may be attributable to cerebellar deficit. Method: Firstly, we provide an overview of recent evidence that proposes a central role for the cerebellum in cognitive skills, in particular those scaffolded by spoken language, in addi-tion to its well-recognised role in motor skills. Secondly, we outline evidence from our labo-ratory that cerebellar function is abnormal in dyslexia. Results: We consider two specific lines of evidence: behavioral, and converging evidence from neuroimaging, which demonstrate significant differences between the dyslexic and con-trol groups. We also apply the same battery of behavioural tests to a group of children who are non-discrepant poor readers. Discussion: Finally, we provide an ontogenetic causal chain for the development of dyslexia in terms of cerebellar deficit from birth, considering the implications of this framework for the key questions in dyslexia research.