Reward Processing, Neuroeconomics, and Psychopathology

Abstract

Abnormal reward processing is a prominent transdiagnostic feature of psychopathology. The present review provides a framework for considering the different aspects of reward processing and their assessment, and highlights recent insights from the field of neuroeconomics that may aid in understanding these processes. Although altered reward processing in psychopathology has often been treated as a general hypo- or hyperresponsivity to reward, increasing data indicate that a comprehensive understanding of reward dysfunction requires characterization within more specific reward-processing domains, including subjective valuation, discounting, hedonics, reward anticipation and facilitation, and reinforcement learning. As such, more nuanced models of the nature of these abnormalities are needed. We describe several processing abnormalities capable of producing the types of selective alterations in reward-related behavior observed in different forms of psychopathology, including (mal)adaptive scaling and anchoring, dysfunctional weighting of reward and cost variables, competition between valuation systems, and reward prediction error signaling.

Keywords: addiction; anhedonia; computational psychiatry; dopamine; major depression; prediction error.

Figure 1

The figure displays four hypothetical scaling functions for subjective value assignment. Function A and A’ represent the same function that has been adaptively scaled based on a different available anchor. Function B (dashed line) shows a function with a pathologically reduced slope, while Function C is anchored by a reward that is so highly valued that most other rewards receive minimal subjective value. Individuals with functions B and C will not be able to differentiate between or be motivated by rewards that are in the left (lower absolute) half of scaled space.