Automatic and affective processing of faces as mechanisms of passing as non-autistic in adolescence.

Passing as non-autistic (PAN) is the phenomenon by which an autistic person does not present as autistic in certain contexts. Despite a proliferation of research on the construct on PAN, no study has yet examined the neurocognitive processes implicated in PAN. This study examined two well-characterized event-related potentials (ERPs) often associated with autism - the N170 and the Late Positive Potential (LPP) - in response to faces as putative mechanisms of PAN. Participants were 44 community-recruited youth (M = 13.36, N = 30) who completed a facial emotion recognition task during EEG recording. PAN was operationalized using best practices (moderation) for calculating the discrepancy between community informant (parent and teacher) and clinician-reported autism symptoms. Results reveal a substantial proportion (approximately 44%) of the community-recruited adolescent sample met criteria for PAN. This status was associated with faster N170 latency to faces, and attenuated LPP amplitude to facial emotions, particularly subtle facial emotions. Findings suggest autistic adolescents who PAN may have more efficient automatic process of, and reduced reactivity to, social stimuli. This study provides the first direct test of a potential neurocognitive mechanism of PAN, supporting emotion regulation-mediated PAN models.