UC Riverside

This dissertation examines event-related potentials (ERPs), measured from electroencephalogram (EEG) recordings, of social and nonsocial reward processing in a predominantly Latinx group of autistic children and teens before and after intervention. Additionally, this investigation proposes using objective, neuroscientific techniques to measure clinical trial effects of oxytocin administration, a neuropeptide associated with social behaviors. Chapter 1 investigates neural response and attenuation of social and nonsocial rewards via the reward positivity component (RewP) in autistic and non-autistic adolescents before and after participation in the Program for the Education and Enrichment of Relational Skills (PEERS) intervention. Increased reward sensitivity was observed during the first half of trials in the autistic group after intervention. Neural correlates of reward also predicted improvements in social behavior. This suggests that participating in PEERS increases reward system sensitivity in autistic teens and that PEERS may be most effective for teens who have “room to grow” in their social reward responsivity. Chapter 2 examines individual differences in anticipation of and response to rewards in autistic and non-autistic teens before and after PEERS. Older adolescents and those with lower parent-reported social motivation prior to participation in PEERS displayed increased social reward anticipation (more robust stimulus-preceding negativity; SPN) from pre- to post-intervention. Participants who displayed more parent-reported social motivation before intervention and were more actively engaged in the PEERS intervention, evidenced by increased social reward processing (more robust RewP) from pre- to post-intervention. Findings support a ‘precision model’ approach to autism intervention with an emphasis on brain-based outcomes. Chapter 3 reviews the therapeutic effects of oxytocin on social behaviors in autistic individuals, focusing on functional outcomes from neuroimaging investigations. Additionally, this chapter proposes a model for clinical trials that includes simultaneous behavioral intervention and oxytocin administration and the hypothesized role of the neural reward system on intervention outcomes. In sum, this dissertation examines neural measures of reward-related brain activity as an outcome measure of intervention in autistic populations and proposes methods for future studies examining combined treatment effects of behavioral and oxytocin interventions.