Navigating our complex social world depends critically on our ability to compare various opportunities and adapt our behavior based on the rewards received from the outcomes of our decisions, other individuals, and larger social groups. Although rewards can promote adaptive decisions-and enhance individual and societal welfare-deficits in the ability to process rewards can impact our physical and mental health, increasing vulnerability to a number of significant public health issues such as addiction, obesity, and psychopathology. Yet, understanding the mechanistic link between reward and different public health issues presents a significant conceptual challenge, as rewards arise in social and nonsocial contexts and are composed of multiple properties that may have different influences on behavior. In particular, affective reward properties signal whether an outcome was positive or negative while informative reward properties signal how to adapt behavior to maximize future rewards. The principal research goal of this project is to study how interactions between multiple brain regions-particularly the striatum and prefrontal cortex-support affective and informative reward properties in social and nonsocial contexts. This research goal complements several training goals that help the applicant acquire new skills (e.g., physiological recordings of arousal and multivariate pattern analysis, MVPA), broaden knowledge base through directed readings and coursework, and prepare for a future career as an independent investigator and instructor. These training goals will contribute to the applicant's long-term success while providing essential new skills needed for the proposed research. The proposed studies utilize functional magnetic resonance imaging (fMRI) combined with physiological measures of arousal and MVPA to investigate two specific aims.
Our first aim i nvestigates the neuroanatomical pathways for reward to test the hypotheses that a) affective and informative reward properties are decoded by distinct subregions of the striatum; and b) these subregions show distinct functional connectivity profiles with prefrontal cortex. This demonstration would have translational potential, elucidating a mechanism for developing treatments that target deficits in distinct reward properties.
Our second aim i nvestigates how social context modulates reward properties, specifically testing the hypothesis that autonomic and neural responses to affective (but not informative) reward properties can be manipulated by social context. Collectively, these findings would further our understanding of the neural and behavioral mechanisms that shape complex social behavior, potentially providing clinicians with new insight into disorders marked by deficits in social reward processing, particularly autism, anorexia nervosa, and schizophrenia.
Deficits in the ability to process rewards is a hallmark of a diverse set of psychopathologies, including depression, autism, anorexia nervosa, and schizophrenia; however, the specific deficits associated with reward processing observed in these disorders (e.g., anhedonia) remain poorly understood. A potential reason for this imprecise association is because the interpretation of rewards can depend on context, which can be social or nonsocial, and the distinct properties imbedded within a reward, such as affective and informative properties that could have different influences on behavior. We hypothesize that the complex nature of rewards can be related to distinct brain mechanisms, potentially providing insight into the precise deficits in reward processing that distinguish different psychopathologies.
