Happy and Angry Faces Elicit Atypical Neural Activation in Children With Autism Spectrum Disorder

BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by significant impairments in social interactions and communication. The ability to accurately perceive and interpret emotional faces is critical to successful social interactions. However, few studies have investigated the spatiotemporal profile of the neural mechanisms underlying emotional face processing in ASD, particularly in children. The current study fills this important gap. METHODS: Participants were 55 children: 28 children with ASD (mean age = 9.5 +/- 1.3 years) and 27 control children (mean age = 8.5 +/- 1.3 years). All children completed an implicit emotional face task while magnetoencephalography was recorded. We examined spatiotemporal differences between the groups in neural activation during implicit processing of emotional faces. RESULTS: Within-group analyses demonstrated greater right middle temporal (300-375 ms) and superior temporal (300-400 ms) activation to angry faces than to happy faces in control children, while children with ASD showed greater activation from 250 to 500 ms to happy faces than to angry faces across frontal and temporal regions. Between-group analyses demonstrated that children with ASD showed similar patterns of late (425-500 ms) posterior cingulate and thalamic underactivity to both angry and happy faces relative to control children, suggesting general atypical processing of emotional information. CONCLUSIONS: Atypical posterior cingulate cortex and thalamus recruitment in children with ASD to emotional faces suggests poor modulation of toggling between the default mode network and task-based processing. Increased neural activity to happy faces compared with angry faces in children with ASD suggests reduced salience or immature response to anger, which in turn could contribute to deficits in social cognition in ASD.