Adaptive reward pursuit: how effort requirements affect unconscious reward responses and conscious reward decisions

Abstract

When in pursuit of rewards, humans weigh the value of potential rewards against the amount of effort that is required to attain them. Although previous research has generally conceptualized this process as a deliberate calculation, recent work suggests that rudimentary mechanisms-operating without conscious intervention-play an important role as well. In this article, we propose that humans can perform a basic integration of reward value and effort requirements without conscious awareness. Furthermore, we propose that conscious awareness of rewards allows for the use of more advanced functions in reward pursuit, which consider the specific course of action that leads to reward attainment. Using a monetary reward priming paradigm that allows us to dissect the performance effects of rewards (i.e., coins of different value) into conscious and unconscious components, we tested this proposal in 3 experiments. Overall, results indicate that people rely on a simple yet adaptive mechanism that unconsciously conserves effort during reward pursuit, because it makes people more reward sensitive whenever more effort is required of the body. Moreover, consciousness supports a more sophisticated mode of reward pursuit, via which people can strategically conserve effort even further. We discuss these findings in the context of decision making, motivation, and consciousness.