Language abnormalities and cerebral structures in autists: phenotypical delineation and voxel-based morphometry by magnetic resonance imaging

• Grant number: 06/07125-0
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2007
• End date: July 31, 2011
• Field of knowledge: Health Sciences - Medicine - Psychiatry
• Principal Investigator: Geraldo Busatto Filho
• Grantee: Geraldo Busatto Filho
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Autism is an early-onset, global and severe developmental disorder which alters the full range of one?s abilities to interact with the environment, including communication skills. A number of neuroimaging studies have attempted to elucidate which brain regions or circuits would be implicated in the pathophysiology of autism. There are data suggesting an association between deficits in communication skills and morphometric or functional abnormalities of brain regions involved in auditory processing in subjects with autism. However, such findings have not always been replicated and the literature in this area remains inconclusive. All functional and structural neuroimaging studies to date have employed methods that involve the delineation of regions of interest (ROI) on circumscribed portions of the brain, and such techniques are subject to limitations. The use of automated image analysis methods would allow voxel-by-voxel comparisons between different groups of subjects (voxel-based morphometry; VBM), overcoming some of the difficulties associated with ROI-based methods and allowing a more comprehensive evaluation of possible brain volumetric abnormalities in patients suffering from autism. Our purpose is to investigate the relationship between the patterns of communication of subjects with autism and regional volumetric abnormalities of gray matter, as assessed with magnetic resonance imagine (MRI) and VBM analyses. This is a cross-sectional study, which will use this methodology to compare regional gray matter volumes between subjects with autism and a healthy control group. All subjects will be assessed, after giving informed consent, with a battery of neuropsychological tests and diagnostic schedules, in order to allow a phenotypic delineation of their pattern of communication and shared attention. MRI data acquisition will be followed by computerized analyses and group comparisons. Our aim, with this study, is to contribute to a greater understanding of the different subtypes of autism and the psychopathological alterations involved in such disease subtypes. (AU)