Changes in neural correlates of outcome feedback processing during implicit learning

In recent years, the neural substrates underlying outcome feedback processing have been investigated in several neuroimaging studies of feedback-based learning. However, what has been missed in these studies is that, the learning process itself also affects the way the feedback is being processed. In this study, we tried to investigate the changes in neural substrates underlying positive and negative feedback processing during goal-directed implicit learning using the Sugar Production Factory (SPF) task in conjunction with an event related functional magnetic resonance imaging. We found a significant learning-related decrease in activity of the right superior frontal gyrus (SFG) in response to positive feedback and a learning-related increase in activity of the precuneus in response to negative feedback. The results demonstrate the changing role of feedback during learning and suggest that learning-related changes in activity of the SFG and precuneus that have been previously reported in several implicit learning studies arise from changes in feedback processing after learning. In addition, the results suggest the important role of positive feedback in early stage and negative feedback in late stage of goal-directed implicit learning.