Neural Correlates of Eye Contact and Social Function in Autism Spectrum Disorder

Abstract
Reluctance to make eye contact during natural interactions is a central diagnostic criterion for autism spectrum disorder (ASD). However, the underlying neural correlates for natural eye contacts in ASD are unknown, and diagnostic biomarkers are active areas of investigation. Here, neuroimaging, eye-tracking, and pupillometry data were acquired simultaneously using two-person functional near-infrared spectroscopy (fNIRS) during live eye-to-eye contact and eye-gaze at a video face in typically developed (TD) and ASD participants to identify the neural correlates of live eye-to-eye contact in both groups. Direct comparisons between ASD and TD participants showed decreased right dorsal parietal activity and increased right ventral temporal-parietal activity for ASD relative to TD during live eye-to-eye contact (p≤0.05, FDR-corrected) consistent with the hypothesis of alternative neural systems for live eye contact. The additional hypothesis that hypoactivity of the right dorsal-parietal regions during eye contact is associated with social performance in ASD was supported by the correlation of right dorsal parietal activity with individual measures of social function: ADOS-2, Autism Diagnostic Observation Schedule, 2nd Edition (r = -0.69); and SRS-2, Social Responsiveness Scale, Second Edition (r = -0.58). That is, as social ability decreased, the neural responses in the right dorsal parietal region to real eye-contact also decreased consistent with a neural correlate for social characteristics in ASD.