Thirty-two healthy adults completed the UG both under social observation and without observation.
Offers were allegedly either randomly generated by the computer or drawn from a pool of offers from previous human players.
One player, the proposer, offers a portion of the money or points to the other, the responder.
If the offer is accepted by the responder, each player receives the amount he was proposed to get.
One of the most common experimental tasks in this line of research is the Ultimatum Game (UG).
In this game, two players have to divide a given amount of money or points amongst themselves according to a simple protocol.
The mere presence of an audience has been shown to impact behavior, facilitating performance on easy or well-trained task, and hindering performance on complex or unfamiliar tasks.
The feedback-locked feedback-related negativity (FRN) but not the P3 was modulated by observation and fairness, with stronger differential coding of unfair/fair under observation.
This effect was strongly correlated with individual levels of social anxiety, with higher levels associated with stronger differential fairness coding in the FRN under observation.
Social context influences social decisions and outcome processing, partially depending on inter-individual differences.
The present study investigated social context-dependent modulation of behavior and feedback processing in the ultimatum game (UG) in relation to inter-individual differences in social anxiety.
Notably, reduced acceptance rates for unfair as compared to fair offers have also been shown for allegedly computer-proposed offers, albeit to a lesser degree than for human-proposed ones. First, this pattern may reflect a tendency of the subjects to vary their responses.