Behavioural and neural limits in competitive decision making: The roles of outcome, opponency and observation.

To understand the boundaries we set for ourselves in terms of environmental responsibility during competition, we examined a neural index of outcome valence (feedback-related negativity; FRN) in relation to an early index of visual attention (N1), a later index of motivational significance (P3), and, eventual behaviour. In Experiment 1 (n = 36), participants either were (play) or were not (observe) responsible for action selection. In Experiment 2 (n = 36), opponents additionally either could (exploitable) or could not (unexploitable) be beaten. Various failures in reinforcement learning expression were revealed including large-scale approximations of random behaviour. Against unexploitable opponents, N1 determined the extent to which negative and positive outcomes were perceived as distinct categories by FRN. Against exploitable opponents, FRN determined the extent to which P3 generated neural gain for future events. Differential activation of the N1 - FRN - P3 processing chain provides a framework for understanding the behavioural dynamism observed during competitive decision making.