Social distance modulates recipient's fairness consideration in the dictator game: an ERP study.

Previous research showed that social distance (e.g., being friends or strangers) influences people's fairness consideration and other-regarding behavior. However, it is not entirely clear how social distance influences the recipient's evaluation of (un)fair behavior. In this study, we let people play a dictator game in which they received (un)fair offers from either friends or strangers while their brain potentials were recorded. Results showed that the medial frontal negativity (MFN), a component associated with the processing of expectancy violation, was more negative-going in response to unfair than to fair offers from friends whereas it did not show differential responses to offers from strangers. The P300 was more positive for fair than for unfair offers irrespective of friends or strangers making the offers. These results suggest that violation of social norms can be detected at an early stage of evaluative processing and that this detection can be modulated by social distance.