Neurobiological Markers of Language and Functioning in Autism (funded through NAAR)

This project investigated the relationship of language acquisition to developments in connectivity between language regions of the brain, as measured by diffusion tensor magnetic resonance imaging in children with autism. Many children with autism fail to develop language or are impaired in their language functioning. Research has shown that language impairment appears to represent the influence of genes that increase susceptibility to autism. An understanding of neurobiological bases of the language deficits in autism will contribute to an understanding of autism’s genetic underpinnings and neurodevelopmental etiology. Evidence of white matter brain abnormalities, particularly of cerebral white matter overgrowth, has emerged from magnetic resonance imaging (MRI) studies of children with autism. These findings have been limited to macrostructural estimates of differences in white matter volume in autism. Dr. Joseph used diffusion tensor imaging (DTI) technology to (a) examine the microstructural integrity and coherence of white matter tracts connecting language-related regions of the cerebral cortex and (b) to evaluate relationship of white matter connectivity to actual language functioning. Dr. Joseph collected anatomical and diffusion tensor brain images from children with autism at age 3 and one year later, and examined the relationship between white matter connectivity in language regions of the brain to measures of children’s language development taken at each time. Dr. Joseph assessed whether microstructural changes in language-related white matter predict acquisition and development of language skills in children with autism.