Date of Award


Document Type

Open Access Dissertation




College of Arts and Sciences

First Advisor

Jane Roberts


This study investigated multiple behavioral indicators of social fear and their relationship to symptoms of autism in preschool boys with atypical and normative development using a stranger approach design. Participants consisted of 101 male preschoolers that were categorized into four groups: boys with fragile X syndrome (FXS; N= 29), FXS with elevated autism symptoms (fxASD; N = 25), idiopathic autism spectrum disorder (iASD; N = 11), and typically developing boys (TD; N = 36). Results indicated specific behavioral responses to a stranger differentiated preschoolers with more severe symptoms of autism (e.g. fxASD and iASD groups) from those with low autism symptomology (e.g. FXS and TD groups). Cross-group comparisons demonstrated that preschoolers with FXS displayed more avoidant gaze from the stranger and their parent during the stranger approach with boys with fxASD exhibiting the greatest proportion of avoidant gaze patterns. The fxASD group also referenced their parent less during the stranger approach in comparison to the FXS and TD groups. The iASD group displayed elevated facial fear in response to the stranger that differentiated them from the FXS, fxASD, and TD groups. No group differences were observed in escape behaviors. Overall, results from this study indicated specific behavioral patterns of social fear in response to a stranger using a normative and cross-syndrome approach. Given the high prevalence of anxiety in FXS and iASD, it is critical to identify how anxiety emerges in atypical and normative development to determine shared and distinguishable traits of anxiety that can be used to inform targeted assessment, prevention and treatment efforts.


© 2017, Jessica Scherr