Neuroplastic differentiation in motor cortex subregions induced by basketball training: A multimodal diffusion MRI...

The primary motor cortex (M1) contains two functionally distinct subregions: effector subregions, responsible for fine motor control, and inter-effector subregions, involved in mind-body coordination and movement planning. However, the impact of long-term exercise training on subregion-specific microstructural plasticity in M1 remains unclear. In this study, thirty-four elite basketball athletes and thirty-five age- and gender-matched non-athletes were included in the analysis. All participants underwent T1-weighted imaging and diffusion MRI scanning. Probabilistic fiber tracking was employed to delineate distinct subregions within the M1. Diffusion MRI techniques, including diffusion tensor imaging, diffusion kurtosis imaging, and neurite orientation dispersion and density imaging, were employed to assess microstructural differences. The athletes' cognitive-motor integration performance was assessed by the swimmy paradigm. Compared to non-athletes, our results indicate that basketball athletes exhibited significantly decreased mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), orientation dispersion index (ODI), and free water fraction (FWF), and significantly increased axial kurtosis (AK) and neurite density index (NDI) in the inter-effector subregions of M1. No significant differences were observed in the effector-specific subregions. Correlation analyses revealed that the difference of reaction times was negatively correlated with MD\AD\RD and FWF, and positively correlated with NDI in the inter-effector subregions. These findings suggest that basketball training induces region-specific microstructural changes in M1, primarily in the inter-effector subregions, which are closely linked to cognitive-motor integration performance. The neuroplastic mechanisms induced by basketball training, as revealed in elite athletes, provide a rationale for exploring sport-based neuromodulatory interventions to optimize cognitive-motor rehabilitation.