Scientists in France have identified a genetic marker for autism that they found in a “less deep fold of Broca’s area” — an area of the brain that specializes in language and communication. The scientists at the Institut de Neurosciences de la Timone, located in Marseille, focused on this “new geometric marker called the sulcal pit.” The sulcal pit is the “deepest point of the sulcus in the cerebral cortex from which points all the folds on the brain’s surface develop.”
Using MRI scans, the scientists analyzed the sulcal pits of 102 young boys aged 2-10 according to three groups: Autism spectrum disorder, pervasive developmental disorder not otherwise specified and “normal developing” children. Comparing the three groups, the depth of the sulcal pit in the brain was less in the autism spectrum disorder group than in the other two groups. The scientists also noted in the autistic children that the deeper the sulcal pits were, the more “impaired the language production” was in the children.
Additionally, the study disproved a previously held belief that brain “cortical folding was complete at birth.” The French scientists noted that some of the brains’ “superficial folding continued to deepen with age in both the autistic and other children.”
Source: http://www.sciencedaily.com/releases/2016/01/160113101121.htm including journal reference Brun Lucile, Auzias Guillaume, Viellard Marine, Villeneuve Nathalie, Girard Nadine, Poinso François, Da Fonseca David, Christine Deruelle. Localized misfolding within Broca’s area as a distinctive feature of autistic disorder. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, 2015; DOI: 10.1016/j.bpsc.2015.11.003 published 12 January 2016.