The cerebellum beyond motor control: cognitive dysfunction in spinocerebellar ataxias

Spinocerebellar ataxias (SCAs) are a group of neurodegenerative disorders primarily characterized by progressive ataxia due to degeneration of the cerebellum and its afferent and efferent pathways. Although cerebellar motor symptoms are the clinical hallmark, considerable phenotypic variability exists across SCA subtypes and among individuals with the same genetic mutation. Depending on the subtype and the extent of cerebellar and extracerebellar involvement, various cognitive domains-including memory, attention, executive function, and language-may also be affected. Notably, the cognitive and limbic functions of the cerebellum are primarily localized to its posterior lobe, where current evidence supports distinct topographic representations. The growing body of literature highlights that cognitive impairment is a prominent and heterogeneous feature of SCAs, with wide variation in severity, affected domains, and progression depending on the underlying genetic subtype.