Neural Mechanisms of Emotion Regulation with Circumscribed Interests in Adults with ASD
Objectives: To examine activation of the PFC in the context of CI under varying states of ER in ASD and control groups.
Methods: A total of 27 adults (ASD=13; Control=14) participated in this study. Groups were matched on age (ASD M=26.1; Control M=27.4) and IQ (ASD M=113.3; Control M=116.3). ASD diagnosis was confirmed with the Autism Diagnostic Observation Schedule. Functional magnetic resonance imaging (fMRI) data were collected during a cognitive appraisal task on a 3T General Electric Signa Excite HD scanner. Each individual was asked to bring in ten photographs of their CI, which were used as stimuli for the task. After receiving standardized training in cognitive emotion regulation techniques, participants viewed each image for 4 seconds (free viewing period) and were then asked to “Think Positive,” or “Think Negative” about CI images while undergoing fMRI. Whole group activation for the pre-instruction [<] post-instruction periods contrast showed activation of the medial PFC (mPFC). A region of interest (ROI) was identified using a 40-voxel sphere in the mPFC from which parameter estimates were extracted.
Results: Contrary to predictions, significant clusters of activation were observed in the medial, rather than lateral prefrontal cortex. ROI analyses of mPFC clusters revealed no group differences between ASD and control subjects during the baseline (pre-instruction) or think-negative conditions (p>0.25). However, for the think-positive condition, the control group showed significantly increased activation in the mPFC, compared to the ASD group, t(17.78)=2.12, p<0.05, d=0.85.
Conclusions: Individuals with ASD showed diminished function in mPFC during think-positive instructions for CI. These findings may indicate impairment in constraining positive affect toward CI, and thus provide evidence for targeting emotion regulation in the context of treatment.