I am entitled to it! Social power and context modulate disadvantageous inequity aversion

Previous research consistently indicated that social power influences one's fairness consideration. However, it is unclear how social power and context jointly affect inequity aversion and whether these processes would be manifested in brain activities. In this study, participants were randomly assigned into either high or low power condition and then took part in a modified ultimatum game (UG) as responders in both gain and loss contexts, with their event-related potentials (ERPs) recorded. Behavioral results showed that powerful participants were more likely to reject unfair offers in both contexts compared with powerless ones. In addition, powerful participants showed a more negative feedback-related negativity (FRN) loss-win difference wave (d-FRN) upon presentation of proposed offers compared with powerless participants only in the gain context. Interestingly, in a later time window, differences of P300 responses to proposed offers were modulated by social power in both gain and loss contexts. These results suggested that powerful people were more sensitive to fairness levels and FRN may manifest fairness consideration in a gain context, but not in a loss context. Meanwhile, P300 is sensitive to fairness considerations in both gain and loss contexts.