Jordan Ezell

Date of Award

Summer 2021

Document Type

Open Access Dissertation



First Advisor

Jane Roberts


This dissertation is comprised of two original research manuscripts broadly examining anxiety and potential correlates in young children with neurodevelopmental disabilities. The first manuscript assessed cardiac regulation during an auditory startle paradigm in young children (3-6 years old) with autism spectrum disorder (ASD), fragile x syndrome (FXS), and neurotypical peers. The second manuscript utilized a new measure developed to capture anxiety in individuals with ASD in order to assess the rate of typical and atypical anxiety and potential risk factors (ASD severity, sex, cognitive ability) for anxiety in preschool children with ASD contrasted to neurotypical preschool children. Collectively, these two manuscripts address the limited understanding and many challenges of measuring anxiety disorders in young children with developmental disabilities and what individual characteristics may serve as risk or protective factors for these children. Additionally, the comparison of children with ASD to children with FXS in the first study can inform both shared risk and divergent features of each disorder. Overall, these studies provide insight into the complex presentation of anxiety in young children with comorbid developmental disorders. Further, this work can inform the early identification of risk factors to develop more targeted interventions in early life to improve long-term outcomes in children with neurodevelopmental disabilities.