A rare birth defect offers a unique perspective on the connectivity theory of autism. Up to one-third of those missing all or part of the corpus callosum, a thick tract of nerve fibers connecting the left and right brain hemispheres, meet the diagnostic criteria for autism, several recent studies suggest.
Spectrum: Autism Research News
Tag: corpus callosum
Three new studies published in March suggest that some infants who have a high risk of developing autism show early differences in brain responses to sight and sound.
Autism may result from reduced anatomical connectivity and functional connectivity between the frontal cortex and more posterior areas of the brain, say Marcel Adam Just and Timothy Keller.
Deletion of CHRM3, a gene on chromosome 1, leads to autism-like behaviors, according to a case study published 16 December in the European Journal of Medical Genetics.
Teenagers with autism have an atypical balance between the right and left sides of the corpus callosum, which connects the two hemispheres of the brain, according to a study published 23 November in the Journal of Autism and Developmental Disorders.
Loss of one copy of TBR1, an autism-linked gene involved in fetal brain development, leads to brain malformations, according to a study published in the September issue of Molecular Syndromology.
Nearly half of children with malformation of the corpus callosum, which links the two hemispheres of the brain, have symptoms of autism, according to a study published 5 October in the Journal of Autism and Developmental Disorders.
Mice lacking one copy of the autism-linked 16p11.2 chromosomal region are thin, deaf and show repetitive behaviors. They also have altered proportions of neurons in their brains, particularly those that express the chemical messenger dopamine. The unpublished results were presented Sunday at the 2012 Society for Neuroscience annual meeting in New Orleans.
MET, a leading candidate gene for autism risk, influences the strength of connections between brain regions involved in social behaviors, and this effect is especially prominent in people with the disorder. The findings are from a large study using several imaging techniques, published 6 September in Neuron.
Seven individuals who have the symptoms of Rett syndrome carry a genetic disruption near, or overlapping with, the FOXG1 gene, according to a report published 27 June in the European Journal of Human Genetics.