Pramipexole to Enhance Social Connections

This study seeks to understand how modulating functioning of the neurotransmitter dopamine affects brain circuits, behaviors, and subjective experiences that are believed to underlie an individual's motivation to establish and maintain positive social connections. This knowledge will help advance understanding of brain mechanisms that can be used to better treat social functioning impairments in people experiencing anxiety or depression. The R61 phase project will evaluate the effects of pramipexole (a medication that increases dopamine signaling in the brain) on responses to different types of positive social cues or contexts. The study drug will be given in a 6-week randomized, double-blind, placebo-controlled trial for individuals with clinical levels of anxiety or depression. Aim 1 will test the hypothesis that pramipexole increases the anticipation of social rewards compared to placebo. Aim 2 will determine which dose of pramipexole (1.0 or 2.5 mg/d) produces a greater effect on social reward anticipation. To achieve these aims, approximately 108 participants (ages 18-50) with clinically elevated anxiety or depression will be randomized across two sites and randomized in equal proportions to one of two doses of pramipexole (1.0 mg/d or 2.5 mg/d) or placebo. They will complete standardized paradigms assessing social reward processing using measures of brain function (fMRI), behavior, and self-report at baseline and week 6. Knowledge gained from this study will help determine the therapeutic potential of targeting the dopamine system to remediate social disconnection.