Abstract
OBJECTIVE: Post-stroke dysarthria (DYS) severely affects communication, yet cortical morphological alterations remain insufficiently characterized. This study applied surface-based morphometry (SBM) to examine cortical changes in DYS and their association with dysarthria severity assessed by the Frenchay Dysarthria Assessment (FDA). METHODS: Forty-eight DYS patients and 72 matched controls underwent MRI. Cortical fractal dimension and gyrification were extracted via SBM. Group differences were tested using two-sample t-tests, and correlations with FDA scores were assessed using Spearman analyses. RESULTS: DYS patients exhibited significantly increased fractal dimension in the left insula and elevated gyrification in bilateral insula, superior temporal and precentral gyri (p < 0.05). Right supramarginal gyrification positively correlated with FDA reflex and respiration subscores (ρ > 0.3, p < 0.05). No significant differences were observed between supratentorial and infratentorial lesions. CONCLUSION: Cortical morphological alterations in insula and supramarginal gyrus may contribute to DYS pathophysiology. SBM provides quantitative markers linking cortical architecture to speech motor control, potentially guiding individualized rehabilitation strategies.