Cortical morphological changes in stroke-associated dysarthria patients

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.