Project Summary Social connections among individuals shape many health outcomes. The progression and treatment of a wide range of neuropsychiatric disorders (e.g., schizophrenia) and disease states (e.g., HIV positivity) depend on individuals' social functioning. As examples, social support systems improve adherence to difficult treatment regimens, whereas dysfunctional social perception exacerbates the mental health challenges of depression and anxiety. Work from our groups in the previous period of support provided evidence for a two-stage model that separated the neural and computational processes that establish a social context from those that guide subsequent social control. Here, we test the hypothesis that these processes reflect the core elements necessary for social competence—how one matches behavior to the current demands of the social environment. Social competence has been recently advanced as a consilient, cross-species framework that explains adaptive decision making in social situations. Moreover, perceived deficits in social competence can drive privilege, ostracism, and systemic discrimination—each of which reinforces larger-scale health disparities. In this project, we will determine how status in a social hierarchy influences mechanisms of decision making, manipulate sensitivity to social hierarchies, and determine how the complexity of the social environment changes decision processes. Our three aims rely on tightly integrated and theoretically well-motivated experiments that use primate electrophysiology, human electrophysiology and neuroimaging, and manipulations of brain function; that adopt parallel tasks and social context manipulations; and that analyze behavior through common computational models. Our work builds on progress from the previous grant cycle that demonstrates how our groups are uniquely positioned to achieve these aims.