Non-monetary reinforcement effects on pro-environmental behavior

While non-monetary reinforcement is often discussed as a promising intervention technique, systematic research on its effectiveness for the promotion of pro-environmental behavior has been scarce. This lack of research is likely due to the difficulty of studying non-monetary reinforcement within existing study designs. Here, we examined the effects of non-monetary reinforcement using a recently developed and validated pro-environmental behavior task. In two preregistered studies (total N = 997), participants could repeatedly choose to exert actual effort in exchange for donations to an environmental organization. Their choices were either followed by potentially reinforcing stimuli (e.g., words of praise superimposed on positively valenced pictures) or not. When accompanied by cheerful animal pictures, these stimuli significantly promoted pro-environmental effort expenditure in Study 2, but not in Study 1. Longer-term effects and spillover to non-reinforced behavior were also examined, but not conclusively supported. These findings illustrate the potential of the presented experimental approach for studying the effectiveness of non-monetary reinforcement in societally relevant domains.