Effects of learning on feedback-related brain potentials in a decision-making task

This study investigated the neural mechanisms of feedback processing during learning. While their event-related potentials were recorded, subjects learned to make a sequence of correct choices in a decision-making task. Each choice was followed by gain or loss feedback. In subjects who learned the task, both the feedback-related negativity (FRN), the P3 and the late positivity decreased in the course of the experiment. In subjects who did not learn the task, only the FRN decreased. Moreover, from all ERPs investigated, only changes in P3 amplitude were able to predict performance. These results suggest that the motivational significance of the feedback decreased in all the subjects, but attentive processing of the feedback only decreased in subjects who learned the task. These findings support the view that learning leads to economy of effort and more efficient processing. Moreover, they show that the P3 with its close relationship to learning should be included in future studies investigating the effects of learning on ERPs.