Integrating context into decision making

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Adaptive behaviour in the world necessitates integrating relevant information from multiple sources and exploiting this information to inform decision processes. Importantly, how an individual optimally integrates these sources of information depends on multiple factors such as environmental factors, current need states, and considered goals. The aim of this project is to understand how the human brain represents contexts and contextually-embedded decision cues, the processes by which these sources of information are integrated to drive choice, and how outcomes are valued with respect to these contexts. In this proposal, we extend previous work by considering how people use internal (current need states) and external context cues (affordances in the environment) to modify the valuation of cues to guide choice, and how these signals unfold dynamically in time. Concretely, we examine (a) how information about changing needs/goals is represented in the brain, (b) how these needs/goals modulate valuation processes, (c) how these neural value signals predict individual choices, and (d) how people discover changes in context to guide these processes.Four fMRI studies are proposed in two projects. The first project will examine how and when people select between different goals when multiple goals must be balanced based on changing needs. People often need to select between multiple goals and adjust actions and evaluations appropriately. One way to deal with this is by organizing different types of goals into a hierarchy of goals, with the higher-order goal of maximizing some form of reward (e.g. advancing in one's career, building a larger social network). Evaluating possible actions or goals can then be based on their weighted relative importance for higher-order goals, which may also depend on factors such as environmental demands or current needs. By using state-of-the-art statistical tools that have been developed in the lab, we will examine how brain systems involved in value (ventral striatum and ventromedial prefrontal cortex) may be modulated by need states, and how neural systems underlying value processing shape the choices that people make. Further, we will investigate how prefrontal regions contribute to representing need states, the current value of holding a goal, and the selection and implementation of new goals. We will use a novel paradigm and analytic strategy to determine how information about the external state is represented as an internal neural context, and critically how these signals guide choices. Then we will leverage these results to examine how people chose to explore their environments to explicitly build mental context models. Our novel experimental design and analytic approach will enable us to explicitly dissociate the neural processes underlying the exploitation of a current context model from those associated with the exploration of contexts.