Atypical Visual Attention Patterns to Social and Non-Social Stimuli in the Broad Autism Phenotype

Background: Differences in attention to social stimuli have been repeatedly observed in eye-tracking studies of individuals with autism spectrum disorder (ASD), particularly in the context of competing information, such as objects associated with circumscribed interests (Sasson et al., 2008; 2011). Evidence of subtle differences in visual attention to social stimuli (e.g., faces) has also been reported in parents of individuals with ASD, and among those parents who display subclinical features of the broad autism phenotype (BAP) in particular (Spezio et al., 2007; Adolphs, et al., 2008). The BAP is a constellation of subclinical traits (pragmatic language, personality features) related to the core features of ASD. This study built on this work by applying eye tracking during a passive viewing paradigm, adapted from Sasson et al. (2008), to examine patterns of visual attention to social, neutral, and circumscribed interest stimuli in parents with and without the BAP.

Objectives: This study examined whether visual attentional patterns to social and nonsocial images in parents of individuals with ASD are similar to those observed in ASD, and whether these differences are related to features of the BAP.

Methods: Thirty parents of individuals with ASD, and 9 controls viewed 12 separate visual arrays on a Tobii T60 eye tracker for 10 seconds each. Each visual array included 12 luminance-matched gray-scale images drawn from both public domain and Sasson et al. (2008) of four image types: smiling people, neutral objects (e.g., table, gloves), objects associated with high interests in ASD (e.g., trains, electronic devices), and those associated with personality features of the BAP, such as rigid or perfectionistic qualities (e.g., calendar, folded clothes). Image types were presented in randomized order to control for potential order effects. Analyses evaluated visual exploration (number of images explored over time) and perseveration (amount of time spent on each image). BAP status (positive + or negative -) was determined using the Modified Personality Assessment Scale (MPAS; Tyrer, 1988).

Results: Visual attention differed across parent groups, and in relationship to BAP features. Similar to patterns reported in ASD (Sasson et al., 2008), parents of children with ASD demonstrated reduced exploration (ps<.05) and increased perseveration (ps<.05) with all image types across slides, relative to controls. These findings were driven by the BAP+ parents, who showed decreased exploration (ps<.04), and increased perseveration (ps<.05) on slides containing ASD-related high interest images, compared to those without BAP features and controls.

Conclusions: Differences in visual attention to social and nonsocial stimuli observed in BAP+ parents bear striking resemblance to patterns observed in ASD, and may suggest key differences in attentional biases related to genetic liability to ASD.