Increased hippocampal volumes in adults with high functioning autism spectrum disorder and an IQampgt;100_ A manual morphometric study

Previous studies concerning the volumes of the amygdala and the hippocampus in autism spectrum disorders (ASD) show inconsistent results. We acquired magnetic resonance images of 30 individuals with ASD and individually matched controls. All participants had an IQ4100 to increase the likelihood of including non-syndromal forms of ASD. Manually defined amygdala volumes showed no significant group difference, while hippocampi were significantly enlarged in ASD. This finding is discussed with regard to the ‘intense world hypothesis’. & 2015 Elsevier Ireland Ltd. All rights reserved.