Project Summary This application seeks to understand how temporally-dynamic information is incorporated into social decisions by investigating the influence of social hierarchy on basic neural and cognitive processes engaged in valuation and learning. While some kinds of social information are stable, others can fluctuate in a way that can shift a social context. Hierarchy, or the organization of individuals according to power and status, is a common feature of most social animal species including humans and is a kind of social information that can exhibit both stable and transient qualities. Knowing a person’s place in society may shape an individual’s decisions to trust or learn from them. Critically, deficits in social decisions, broadly, are observed in psychopathologies ranging from autism to schizophrenia and potentially, such deficits might arise from maladaptive monitoring and integration of time-varying social features such as hierarchy. While stable hierarchical identities like socioeconomic status or gender could influence a person’s decision to trust or learn from professionals like medical doctors or teachers, situational contexts can further transiently increase or decrease perceived differences in power or status (e.g., being at a hospital or in a classroom). The intersection between these stable and transient features of hierarchy are especially important because power dynamics may engage distinct or overlapping mental processes. For instance, patients might be more proactive in suggesting alternative therapies if they perceive healthcare providers to be of similar social status. These processes might further modulate different kinds of decisions depending on implicit goals. Affiliative and competitive goals might be under dissociable influence of hierarchy if the neural and cognitive processes involved in the decisions only partially overlap. While traditional psychological experiments have investigated human social decisions using anonymous or unknown partners (which offers important experimental control), this limitation is detached from real-world scenarios in which humans acquire dynamic information about the people with whom they are interacting. Studying the neural mechanisms involved in these decisions can provide information about the basic cognitive processes that contribute to maladaptive decision making. Specifically, computations in brain regions like the striatum, prefrontal cortex, and temporoparietal junction supporting reward maximization over costs, mentalizing, and learning abilities are important for interactions with others. Notably, the functional roles of these regions are consistently implicated in clinical disorders like schizophrenia and autism, which share common social behavior deficits. Therefore, understanding the brain mechanisms involved in the integration of social hierarchy with learning and decision making can provide transdiagnostic insight about social behavior. This examination of interaction...