Date of Award

Spring 2020

Document Type


Degree Name

Master of Science (MS)



First Advisor

Vaughan Van Hecke, Amy

Second Advisor

Kodak, Tiffany

Third Advisor

Magnus, Brooke


The prevalence of Autism Spectrum Disorder (ASD) continues to rise as researchers seek to examine the physiological links to social and communication challenges. The Social Brain, neuroanatomical structures which play a role in social cognition, is proposed to be linked to the social and communication challenges associated with ASD. An area of rapidly growing research is the evaluation of social skills interventions, which target social challenges present in Autistic individuals. Advances in technology, have allowed for these interventions to be examined in regards to physiological changes (e.g., electroencephalogram asymmetry and coherence) as outcome variables. Amongst these interventions, the Program for Education and Enrichment of Relational Skills® has been shown to be efficacious across several countries and different cultural backgrounds. The present study investigated neurophysiological outcomes in adolescents who receive PEERS®, compared to waitlist control and NT control groups. Structural magnetic resonance imaging (MRI) scans were utilized to evaluate changes in volume, cortical thickness, and surface area of adolescents across a randomized controlled-trial of PEERS®. We hypothesized that 1) Social Brain structures between NT and ASD groups would be significantly different at pre-intervention, with the exception of the Amygdala; 2) structural changes from pre- to post-intervention would be found in the ASD group that received PEERS®; and 3) significant structural changes found across time points would predict changes across time in questionnaire measures of social and communication challenges. Results indicated: a) partial support of Hypothesis 1, showing that Amygdala volumes did not differ across groups, but contrary to our hypothesis the remaining structures also did not show a significant difference at pre-test between groups; b) partial support of Hypothesis 2, indicating bilateral amygdala, left caudal anterior cingulate cortex, and left superior temporal gyrus volumes changed differentially between groups over the course of PEERS®; c) Hypothesis 3 was not supported. In conclusion, this study is the first to indicate differential neuroanatomical volumetric changes over the course of a social skill intervention for Autistic individuals that received the intervention, contrasted to those that did not receive the intervention.

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Psychology Commons