Visual Processing of Social Information In Adults and Children

Background: Healthy infants and adults have consistently shown a preference for gazing at faces in their environment (Pelphrey et al., 2002; Hoehl et al., 2009). Many researchers theorize that this tendency signifies an innate predisposition for detection of socially relevant information. Current theory asserts that this is an advantageous mechanism that prioritizes processing of social versus non-social information. Conversely, individuals on the autism spectrum spend less time gazing at faces; a difference that has been shown across eye tracking investigations (Klin et al., 2002; Dalton et al., 2006; Wang et al., 2007.) 

Objectives: The goals of this study were to test differences in attention to facial expressions while viewing ironic and sincere scenarios and to determine the nature of the relationship between attention to these facial expressions and performance on measures assessing an individual’s presentation of traits associated with autism.

Methods: Using a Tobii T60 eye tracker, this study examined attention to faces by evaluating the visual processing of potentially ironic cartoon scenarios. Thirty-three neurotypical adults (18-30 years) and a pilot sample of 9 neurotypical children (3-7 years) viewed a random sequence of 20 vignettes that were equally likely to be ironic or sincere. Ironic scenarios featured a speaker delivering a remark in a sarcastic tone accompanied by a negative face (e.g., anger, disgust). Sincere scenarios portrayed a speaker delivering a remark in a genuine tone accompanied by a positive face (e.g., happiness). At the end of each vignette, participants were asked to determine if the speaker meant what they said. Time spent gazing upon the speaker’s face was recorded. Twelve control scenarios that featured a speaker in a neutral situation delivering a neutral remark with either a happy (positive condition) or a sad (negative condition) face were also presented. This determined if there were differences between the salience of faces expressing opposite emotions. In all conditions, expressive faces remained on the screen until the participant gave their response concerning the speaker’s intent. Additionally, adult participants received the Broad Autism Phenotype Questionnaire (BAPQ; Hurley et al., 2006) to detect autism traits by providing subscores for aloofness, rigidity and pragmatic language. Child participants received the Social Responsiveness Scales (SRS; Constantino, 2005) to reveal social deficits associated with autism.  

Results: Paired samples t-tests and RM ANOVA both revealed that adults and children spent significantly more time gazing upon sarcastic versus sincere faces. This trend occurred during and after the sarcastic statement was delivered, but not during and after the participants were asked to determine the speaker’s communicative intent. The relationship between fixation times upon faces and BAPQ or SRS scores continues to be analyzed.  

Conclusions: Thus far, these results suggest that typical adults and typically developing children are naturally attuned to expressive faces carrying social information and are efficient at processing them in order to understand someone's intended meaning (Wang et al., 2006; 2007).