About Eighty Percent of Brain Grey Matter Shows Autism Signs in fMRI

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with its symptoms appearing from early childhood. Behavioral modifications, special education, and medicines are used to treat the ASD; however, the effectiveness of the treatments depends on early diagnosis of the disorder. The main approach in diagnosing ASD is currently based on clinical interview and valid scales; however, methods based on brain imaging could also be possible diagnostic biomarkers for the ASD in the future. To identify the amount of information the functional Magnetic Resonance Imaging (fMRI) reveals on ASD, we reviewed 292 task-based fMRI studies on ASD individuals. We observed that face perception, language, attention, and social processing tasks were mostly studied in ASD. In addition, 73 brain regions, estimated as about 83% of brain grey matter, showed an altered activation between the ASD and normal individuals during these four tasks, either a lower or a higher activation. Using imaging methods such as fMRI for the diagnosis or prediction of ASD is a big aim; however, works like this could be the initial steps to make it happen. This study is part of a systematic review with the registration number of CRD42017070975.