We present a theory and neurocomputational model of how specific brain operations produce complex decision and preference phenomena, including those explored in prospect theory and decision affect theory. We propose that valuation and decision making are emotional processes, involving interacting brain areas that include two expectation-discrepancy subsystems: a dopamine-encoded system for positive events and a serotonin-encoded system for negative ones.The model provides a rigorous account of loss aversion and the shape of the value function from prospect theory. It also suggests multiple distinct neurological mechanisms by which information framing may affect choices, including ones involving anticipated pleasure. It further offers a neural basis for the interactions among affect, prior expectations and counterfactual comparisons explored in decision affect theory. Along with predicting the effects of particular brain disturbances and damage, the model suggests specific neurological explanations for individual differences observed in choice and valuation behaviors.Keywords: computational neuroscience; decision making; emotion; framing; prospect theory. what kind of career to pursue? In traditional economics, the standard answer is that people decide by maximizing expected utility, but psychologists have found many problems with this kind of decision theory as a description of human behavior (e.g., Camerer, 2000;Kahneman & Tversky, 2000;Koehler, Brenner, & Tversky, 1997;Rottenstreich & Hsee, 2001;Tversky & Kahneman, 1991). Economists commonly take preferences as given, but from a psychological point of view it should be possible to explain how preferences arise from cognitive and affective processes.Work in this spirit has made tremendous progress in revealing key features and dynamics missed by theories disconnected from the study of cognitive, emotional and socially motivated phenomena, such as a common hypersensitivity to losses over equivalent gains (Kahneman & Tversky, 1979) and the affective influence of prior expectations and counterfactual comparisons on preference judgments (Mellers, 2000). Moreover, with the rise of cognitive and affective neuroscience, it should be possible to identify precise neural mechanisms underlying these behavioral-level explanations of why people make the choices that they do.We propose neural affective decision theory as a psychologically and neurologically realistic account of specific brain mechanisms underlying human preference and decision. The theory consists of four principles, which we shall list here and describe in detail later:1. Affect. Decision making is a cognitive-affective process, crucially dependent on emotional evaluation of potential actions.
Brain.Decision making is a neural process driven by coordinated dynamic interactions among multiple brain areas, including parts of prefrontal cortex as well as major subcortical systems.3. Valuation. The brain forms preferences via interacting but distinct mechanisms for positive and negative outcomes, encode...