Abnormal development pattern of the amygdala and hippocampus from childhood to adulthood with autism.

Using magnetic resonance imaging to determine neuropathology in autism spectrum disorders, we report findings on the volume of the amygdala and hippocampus in autistic children. The volumes of amygdala, hippocampus and total brain were obtained by volbrain and their volumes were measured in young people (6.5-27.0 years of age) that comes from ABIDE dataset. Although there was no significant difference in total brain capacity between groups, autistic children (6.5-12.0 years of age) had larger right and left absolute and relative amygdala volumes than the control group. There was no difference in amygdala volume between adolescence (13-19 years old) and adults (20-27 years old). Interestingly, the volume of the amygdala in typical developing children increased significantly from 6.5 to 27 years of age. Thus, amygdala in children with autism was initially small, but no age-related increases were observed in normal developing children. The right absolute hippocampal volume of autistic patients was also larger than that of normal adults, but not after controlling the total brain volume. These cross-sectional findings suggest that abnormal patterns of hippocampal and amygdala development continue into adolescence in autistic patients.