Design: Participants were required to learn the response that was associated with a specific stimulus by using feedback to guide behavior. We examined the electrophysiological changes associated with correct and incorrect responses in the initial stages of learning, as well as later in learning when the subject had made at least four consecutive correct choices to a specific stimulus. The medial frontal negativity (MFN) was used to examine conflict in remembering the correct stimulus-response mappings.
Results: The data revealed that errors late in learning were associated with the largest negative amplitude of the MFN This suggests conflict in remembering the correct response associated with the current stimulus. Source localization using GeoSource (EGI, www.egi.com) determined the cortical source of the MFN was estimated to be in the caudal region of the ACC. Another component, the FRN, was sensitive to the nature of the feedback, being more negative to error feedback (data not shown). Only a trend was found for the FRN to be more negative early in the learning stage compared to later, suggesting involvement during both stages of learning. The cortical generator of the FRN was found to be in the rostral region of the ACC
Previously published in Brain Res - Luu, P., Shane, M., Pratt, N.L., & Tucker, D. (2009). Corticolimbic Mechanisms in the Control of Trial and Error Learning Brain Research. 1247, 100-113.