The Broad Autism Phenotype in the General Population: Evidence Through Eye-Tracking
The broad autism phenotype (BAP) has been defined both behaviorally and biologically. There has been little research on the association of the BAP, behaviorally defined, with neural or cognitive biomarkers typically associated with Autism Spectrum Disorder (ASD). People diagnosed with ASD tend to show reduced gaze fixation toward the eye region, but much less eye-tracking research has been done related to the BAP (Boraston & Blakemore, 2007). In this study, we sought to assess eye gaze patterns in people with the behaviorally defined BAP, as defined by a score of 30 or above on the Autism Spectrum Quotient (AQ; Baron-Cohen et al., 2001). It was hypothesized that the BAP group participants would exhibit longer average fixation duration to the eye region during an emotion recognition condition, relative to a free-viewing condition, whereas the comparison group participants (defined as an AQ score of 24 and below) would not show a difference in fixation duration to the eye region between conditions. Nine hundred and thirty-nine undergraduates completed an online survey, and 45 of these students (15 BAP group and 30 comparison group) participated in the eye-tracking session, where they viewed a series of human faces, each presented twice within a condition. Results revealed a significant negative relationship between social anxiety and eye region fixation duration in the free-viewing condition, for both presentations of faces. Contrary to expectation, BAP predicted longer eye region fixation duration in the free-viewing condition, for the second presentation of faces. Possible explanations for these surprising findings are discussed.