[Neuropsychological comparison between corticobasal degeneration and progressive supranuclear palsy]

We conducted a neuropsychological comparison among cases with corticobasal degeneration (CBD; n = 8), those with progressive supranuclear palsy (PSP; n = 5) and healthy control subjects (n = 12) using an extensive neuropsychological battery assessing memory and executive functions. There were no significant differences among three groups for age, education, scores on the Mini-Mental State Examination and Zung's self-rating depression scale. Both patient groups showed retrieval impairment without recognition difficulties, and a dysexecutive syndrome. Along with those similarities, we observed some differences between CBD and PSP patients. Memory impairments in CBD patients were more marked than PSP patients in Rey's complex figure test, while they were less prominent in Rey's auditory verbal learning test. Perseverative errors of Nelson in Wisconsin card sorting test (Keio version) were more marked in CBD patients than in PSP patients. These two diseases showed memory and executive dysfunctions probably due to subcortico-frontal dysfunction. Some neuropsychological differences may help to distinguish CBD clinically from PSP.