Cerebellar Tracts Microstructural Characteristics and Severity of Language Impairment in Post-stroke Patients with Aphasia: A DTI Study.

Aphasia is a language impairment resulting from stroke. While numerous studies have explored the association between supratentorial white matter damage and post-stroke aphasia using diffusion tensor imaging (DTI), the role of infratentorial structures, particularly the cerebellum, remains underinvestigated. Evidence suggests that the cerebellum may play a supportive role in language processing, but its contribution across different aphasia types is not well understood. This study aimed to explore cerebellar white matter involvement in individuals with Broca's, conduction, and anomic aphasia using DTI. Using OpenNeuro data from 155 post-stroke patients, including patients with Broca's, anomic, and conduction aphasia, we examined cerebellar DTI metrics in relation to language function assessed by the Western Aphasia Battery (WAB). We examined the association between WAB scores and DTI findings using a linear regression model adjusted for age at onset and sex. Our study observed a significant difference among three groups of post-stroke patients with aphasia regarding their performance on the WAB test. Unlike individuals with conduction and anomic aphasia, post-stroke patients with Broca's aphasia exhibited associations between QA (Quantitative Anisotropy) and RDI (Restricted Diffusion Imaging) in the superior,middle, and bilateral inferior cerebellar peduncles with WAB-AQ. However, these associations did not remain significant after FDR correction. These findings suggest a potential role for cerebellar pathways in language impairment in post-stroke Broca's aphasia. Future research should apply advanced imaging and broader language assessments to clarify the role of the cerebellum in aphasia severity.