Anatomical correlates of dyslexia: frontal and cerebellar ®ndings

In this study, we examined the neuroanatomy of dys-lexic (14 males, four females) and control (19 males, 13 females) children in grades 4±6 from a family genetics study. The dyslexics had speci®c de®cits in word read-ing relative to the population mean and verbal IQ, but did not have primary language or motor de®cits. Measurements of the posterior temporal lobe, inferior frontal gyrus, cerebellum and whole brain were collected from MRI scans. The dyslexics exhibited signi®cantly smaller right anterior lobes of the cerebel-lum, pars triangularis bilaterally, and brain volume. Measures of the right cerebellar anterior lobe and the left and right pars triangularis correctly classi®ed 72% of the dyslexic subjects (94 % of whom had a rapid automatic naming de®cit) and 88 % of the controls. Th