Effects associated with long-term training in sports requiring high levels of strategy on brain white matter structure in expert players: A DTI study

existed between fractional anisotropy (FA) values and training time. Consistent with our hypothesis, the white matter microstructure properties of both the dorsal and ventral pathways in expert table tennis players significantly differed from those in nonplayers. Specifically, FA values in the bilateral corticospinal tracts, which mainly connect brain regions in the dorsal sensorimotor system, were higher in experts than in nonplayers. Compared with nonplayers, expert players also had higher FA values in the left inferior longitudinal fasciculus and bilateral inferior occipitofrontal fasciculus of the ventral pathway, which are involved in higher-level cognitive processing, such as semantic processing or thinking. By contrast, no white matter region showed a higher FA value in nonplayers than in expert players, and no region was found with axial diffusivity difference between the groups. Additionally, radial diffusivity was lower in the left superior longitudinal fasciculus and bilateral inferior occipitofrontal fasciculus in experts than in nonplayers. Correlation analysis of the expert group showed significant positive correlations between training time and FA values in both the left superior longitudinal fasciculus in the ventral pathway and bilateral corticospinal tracts in the dorsal pathway. Taken together, these findings suggest that enhanced structural integrity of the white matter in both the dorsal and ventral pathways is associated with long-term, expert table tennis training. The observed structural plasticity is conducive to promoting cognitive processing of concrete sensorimotor and abstract information, which would enable expert players to excel at sports requiring a high level of strategy.