Atypical Face Perception in Autism: A Point of View?

Abstract

Face perception is the most commonly used visual metric of social perception in autism. However, when found to be atypical, the origin of face perception differences in autism is contentious. One hypothesis proposes that a locally oriented visual analysis, characteristic of individuals with autism, ultimately affects performance on face tasks where a global analysis is optimal. The objective of this study was to evaluate this hypothesis by assessing face identity discrimination with synthetic faces presented with and without changes in viewpoint, with the former condition minimizing access to local face attributes used for identity discrimination. Twenty-eight individuals with autism and 30 neurotypical participants performed a face identity discrimination task. Stimuli were synthetic faces extracted from traditional face photographs in both front and 20° side viewpoints, digitized from 37 points to provide a continuous measure of facial geometry. Face identity discrimination thresholds were obtained using a two-alternative, temporal forced choice match-to-sample paradigm. Analyses revealed an interaction between group and condition, with group differences found only for the viewpoint change condition, where performance in the autism group was decreased compared to that of neurotypical participants. The selective decrease in performance for the viewpoint change condition suggests that face identity discrimination in autism is more difficult when access to local cues is minimized, and/or when dependence on integrative analysis is increased. These results lend support to a perceptual contribution of atypical face perception in autism.

Face perception develops similarly across viewpoint in children and adolescents with and without autism spectrum disorder

“…The synthetic face images of the present study were similar to those used by Wilson et al (2002), Habak et al (2008), and Morin et al (2015). A detailed description of these stimuli is provided in Wilson et al (2002).…”

“…Similarly, Wolf et al (2008) asked participants to match facial identities across a 458 change in viewpoint, and reported that children with ASD were significantly less accurate than TD children. In a more recent study from our group, Morin et al (2015) presented target and choice faces in same-view (front, side, inverted) and view-change (front [target], side [choices]) conditions, and asked participants to discriminate between facial identities. Results indicated that adolescents and adults with ASD performed poorer than TD participants only in conditions of viewpoint change, consistent with the findings from previous studies.…”

“…The present study expanded upon the findings of Morin et al (2015) with a novel focus on age-related changes, and the transition from childhood to adolescence. We examined the development of face percep-tion in a large and clinically well-defined sample of children and adolescents with ASD.…”

“…Specifically, we assessed face identity discrimination across viewpoint, manipulating access to local and global facial information. We included synthetic face images similar to those used by Morin and colleagues (Morin et al, 2015;Wilson, Loffler, & Wilkinson, 2002) but adapted the testing procedures for younger participants (see Method). These images were unique in that they allowed for the precise control of facial geometry and excluded extraneous, detailed information, such as wrinkles, shadows, and texture (Habak et al, 2008).…”

Social cognition in autism: Face tuning

“…Individuals with autism fail to engage in the emotionally or socially relevant content of social scenes by devoting substantially more time to the area of mouth than to eyes 20 . Face identity discrimination in autism is more difficult when access to local cues is minimized, and when dependence on integrative analysis is increased 21 . Other studies demonstrate, however, deficits of ASD individuals in configural face processing (for review, see ref.…”