Competition influences outcome processing involving social comparison: An ERP study

In a complicated social context, outcome evaluation involves not only oneself but also others in relation to the self (i.e., social comparison). Previous event-related potential (ERP) studies have investigated the processing of social comparison-related outcomes when one's interests are independent of the interests of others (i.e., noncompetition circumstances). However, it is unclear how social comparison-related outcomes are processed in the brain when there are conflicts of interest between oneself and others (i.e., competition circumstances). To address this issue, participants in the current study were asked to perform an attentional task with several peers and were subsequently presented with self-related outcomes (i.e., the performance difference between the current trial and several preceding trials) and social comparison-related outcomes (i.e., the performance difference between oneself and their peer). Importantly, rewards and punishments were based on social comparison-related outcomes in the competition condition and on self-related outcomes in the noncompetition condition. ERP results revealed that in the competition condition, positive outcomes involving social comparison elicited a greater P300 response than negative outcomes, whereas this effect was not observed in the noncompetition condition. Additionally, there was generally a larger late positive potential (LPP) response to negative outcomes involving social comparison than to positive outcomes only when one obtained a self-related positive outcome in the competition condition. These findings suggest that competition might strengthen outcome processing involving social comparison at late time ranges relying on self-related outcomes to some extent.