Atypical modulation of cognitive control by arousal in autism.

We examined the effects of viewing high-arousal pictures on regional brain activations elicited by a cognitive control task in participants with high-functioning autism and neurotypical controls. Specifically, using event-related functional magnetic resonance imaging, we assessed the effects of brief presentations of highly arousing pictures (i.e., both very pleasant and very unpleasant) on the processing of stimuli requiring cognitive control. Similar to previous findings, when stimuli with high cognitive control demands were preceded by low-arousal pictures, individuals with autism demonstrated regional brain activations that were comparable to neurotypical control individuals. When the presentation of the cognitive control stimuli was preceded by high-arousal pictures, however, the control group was characterized by relatively greater activation in the right lateral midfrontal cortex in response to cognitive control stimuli. In contrast, preceding high-arousal stimuli did not modulate activity elicited in this region by cognitive control stimuli in the autism group. Differential modulation of right lateral midfrontal activation by high-arousal stimuli in autism is consistent with the "inefficiency model" of brain functioning in autism spectrum disorders, and contributes to a growing body of evidence that autism may be characterized by anomalous sensitivity of cognitive control brain regions to social-emotional context.