Demand Characteristics in Episodic Future Thinking: Delay Discounting and Healthy Eating

Steep delay discounting, or rapid devaluation of future outcomes, is one mechanism that can account for the chronic selection of smaller-sooner over larger-later outcomes; that is, impulsive choice. Because steep delay discounting is correlated with maladaptive behavior, researchers have explored methods for reducing discounting. One empirically supported method is episodic future thinking (EFT), or vividly imagining one's future before completing the discounting task. However, EFT procedures may include demand characteristics, which could account for some its beneficial effects. In two experiments, demand characteristics were evaluated by having participants read a description of the interactions between a fictional experimenter and a human subject in a typical EFT study. When subsequently asked to indicate what the fictional experimenter expected the human subject to do after the EFT exercise, participants correctly deduced the experimenter's hypotheses: that EFT would reduce impulsive choice (Experiment 1A) and consumption of junk food (Experiment 1B). Future research should evaluate and control for the possibility that demand characteristics are at least partially responsible for the beneficial effects of EFT. Public Health Significance Episodic future thinking (EFT) decreases impulsive choice and holds promise for treating addictive disorders. The present studies reveal a potential problem with EFT procedures: that participants can deduce the experimenter's hypotheses that EFT should decrease impulsive behaviors. When aware of the hypotheses, participants' behavior may be biased to support them (a good-subject effect); these findings suggest research is needed to evaluate the benefits of EFT when demand characteristics are neutralized.