The role of brain oscillatory activity in processing the informative value of feedback during rule acquisition.

Information conveyed through feedback enables individuals to learn new routines and better adapt to their environment. However, the neural mechanisms of rule-related information of feedback have not been fully elucidated. Herein, we quantified the effect of informative value on feedback via a rule induction task (RIT), in which participants were required to find the correct sorting rule based on feedback. To disengage the effects of informative value and valence on feedback in the RIT, a control task was developed in which feedback only involved the valence aspect and no reference for subsequent selections. We measured power and intertrial phase clustering (ITPC) values via EEG to determine the neural mechanisms of rule-related feedback. The results revealed that (1) differences in oscillatory activities between positive and negative feedback were only observed during the control task, and no such effect was found in the RIT task. This finding suggests that the participants paid more attention to rule-related information than to the correctness of feedback during rule learning. (2) The task differences under positive or negative feedback were associated with the delta-theta and alpha-beta bands, and this pattern was similar within the frontal and parietal regions. These findings suggest that the processing of rule-related information of feedback relies on broad frequency bands within the frontoparietal cortex to facilitate rule information integration. In summary, these findings indicate that multiple frequency bands are involved in encoding the informative value aspect of feedback, and individuals rely on this aspect of feedback rather than valence during rule learning.