An Adaptive Response to Uncertainty Generates Positive and Negative Contrast Effects

Abstract

Choice in Changing Environments Animals, including humans, generally tend to judge the world on relative, rather than absolute, terms. For example, the value of a particular object or reward is generally determined based on comparison to other rewards we have received in the past or to those that others have received. Such contrast effects can have negative or positive impacts on our behavior. McNamara et al. (p. 1084 ) used an optimality model to show that contrast effects could evolve as an adaptive response to environmental instability and unpredictability.