ATXN3 and autosomal dominant cerebellar ataxia: A longitudinal investigation of SCA1, SCA2, SCA3, SCA6, and SCA7 cognition progression showed impairment in Stroop C-W Test and oral SDMT, which reflected a relatively slow psychomotor speed of all the SCA subtypes, but the sample sizes were small in all the subtypes (Moriarty et al., 2016).