Date of Award


Degree Name

Master of Science in Education


Behavior Analysis and Therapy

First Advisor

Rehfeldt, Ruth Anne


Behavior analysis has long been a field which has rooted itself in science and observable, measurable behavior, long avoiding the subject of private events such as thoughts and emotions and largely focusing applied work with individuals with disabilities. However, the prevalence of anxiety and depression among adolescents and young adults with autism spectrum disorder (ASD) and other developmental disabilities (DD) is an issue which can hinder the development of social relationships and success in higher education. The current study used a pre- post- group design to evaluate the efficacy of implementing two components of Acceptance and Commitment Therapy (ACT) with adolescents and young adults with ASD to change the function of verbal statements made about the self while discussing a negative thought. Additionally, participants wore a biofeedback wristband to measure their heart rate while discussing the thought before and after completing either an acceptance + defusion activity or a control activity. The findings of this study suggest that an acceptance + defusion activity was effective in increasing pragmatic statements and statistically significant in decreasing unworkable statements. Although the findings regarding the changes in heart rate were not statistically significant, future studies should continue to investigate ACT's effects of private events such as thoughts, feelings, self-rules, and physiological processes. With limited research within the field of behavior analysis focusing on using ACT with individuals with ASD and DD, the results of this study support a clinical utility of ACT to improve the lives of individuals with ASD.




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