The (a) detected changes within the subependymal cell layer with subependymal nodular dysplasia, (b) subcortical and periventricular heterotopias and (c) neocortex, archicortex, dentate gyrus, cornu Ammonis and cerebellar dysplasia reflect focal modification of neurogenesis, migration and alterations of the cytoarchitecture of brain cortex, subcortical structures and cerebellum in autism. Detection of dysplastic changes only in one control brain and of the broad spectrum of focal developmental alterations in the brains of 92% of the autistic subjects indicates that focal changes are a reflection of global developmental abnormalities and that regional changes may have their own contribution to the clinical heterogeneity of autism.
