Reward Processing and Exposure Therapy for Social Anxiety Disorder

A substantial number of individuals do not achieve clinically significant symptom relief from exposure therapy, or they may experience return of fear following completion of exposure therapy. This clinical trial aims to intervene on one potential reason exposure therapy's success is mitigated: anhedonia. Anhedonia is characterized by physiological, behavioral, neural, and self-report deficits in reward processing - where reward processing includes anticipation of reward (positive experiences, such as social connection, food, personal achievement), engaging in effort for reward, feeling motivated for reward, savoring reward when it occurs, taking responsibility for the occurrence of reward, and learning what leads to reward. In basic scientific studies of non-humans and humans, poor reward processing is associated with poor extinction of fear (i.e., poor reduction of fear), and anxiety disorders (e.g., social anxiety disorder) often have elevated anhedonia. Therefore, individuals who are both anxious and anhedonic likely experience deficits in extinguishing fear, which is a core process of exposure therapy. Methods of improving reward processing and anhedonia may thus increase the efficacy of exposure therapy.

The present clinical trial will recruit individuals who are clinically socially anxious, have elevated public speaking anxiety, and have anhedonia / poor reward processing. Participants will all do Exposure Therapy for public speaking anxiety, but before doing so, they will be randomized to one of two treatment conditions: the behavioral portion of Positive Affect Treatment (PAT-B; to increase reward processing and reduce anhedonia), and Relaxation Treatment (comprised of mindfulness, diaphragmatic breathing, and progressive muscle relaxation). Assessments including a public speech behavioral approach task, questionnaires, and fear conditioning. The behavioral approach task and questionnaires will be conducted before participants' first treatment (Pre Tx; before PAT-B or Relaxation Treatment), after their first treatment (Post Tx-1), after Exposure Therapy (Post Tx-2), and three months after completing Exposure Therapy (3-Month Follow-Up). The fear conditioning task will be conducted before participants' first treatment (Pre Tx; before PAT-B or Relaxation Treatment) and after their first treatment (Post Tx-1); this will be done either in an fMRI or non-fMRI setting, depending on whether participant has MRI contraindications or based on study needs.