Neural correlates of motor expertise: Extensive motor training and cortical changes

Over the last two decades, there were many investigations on motor expertise but inconsistencies across findings exist. Thus, to unravel these discrepancies, we conducted a novel literature review, applying stricter inclusion criteria relative to those used in previous reviews. Consequently, this paper reviews the most recent MRI and fMRI literature which investigated structural and functional changes underlying motor expertise, defined as being the result of intensive and extensive motor training reflected by a sheer volume of at least several thousand hours. Changes were documented on a local level and on a network level where interactions between pairs of brain components were mainly considered. This review reveals that changes occur induced by lengthy-extensive motor training and that this training shapes the human brain in areas related to the execution of the task. It also highlights the coexistence of different cortical patterns within and between various brain areas/systems which makes it difficult to interpret. Using a large-scale complex network approach based on graph theory facilitates the identification of organizational patterns in brain network and thus enable interpretation. Other recommendations for future research are: attention to participant recruitment, use of histological/biochemical techniques, and combination of sMRI and task-free/task-related fMRIs.