Augmenting Exposure Therapy for Social Anxiety With Transcranial Direct Current Stimulation

This study will examine whether transcranial direct current stimulation (tDCS) can be used to improve outcomes from exposure therapy for social anxiety disorder, and facilitate extinction of fear responding toward individuals outside one's own ethnic group (i.e., ethnic out-group members).

Although exposure therapy is among the most powerful treatment techniques for social anxiety, many individuals do not achieve full remission. Furthermore, some research suggests that fear responding toward ethnic out-group members may be more resistant to extinction. Enhancing activation of the mPFC during exposure therapy may improve overall response to treatment, and also facilitate extinction of fear toward ethic out-groups. Researchers have found that greater mPFC activation during exposure therapy is associated with better outcomes, and that transcranial direct current stimulation (tDCS) can be used enhance learning and cognition with no known serious adverse effects. This study will therefore examine whether active/anodal (versus sham) tDCS targeting the mPFC (a) enhances overall reductions in social anxiety symptoms, and (b) facilitates extinction of fear responding toward ethnic/racial out-groups for both Latino and Caucasian/non-Latino participants. Participants will receive either active/anodal tDCS or sham tDCS during a brief exposure therapy intervention involving public speaking in a Virtual Reality (VR) environment. The public speaking audience in the VR environment will alternate between audiences that are either matched or unmatched to the participant's ethnicity (in a randomly assigned order). Participants' fear reactivity will be assessed with behavioral, physiological, and subjective measures at baseline, post-treatment, and follow-up.