[Neuropsychological investigation in multiple sclerosis].

We studied neuropsychological performance in 10 patients with multiple sclerosis (MS). Neuropsychological test batteries consisted of Mini-Mental State Examination, Digist Span, Paired Associate Learning Test (PAL), Benton Visual Retention Test, Kohs Block-Design Test, Digit Symbol Subtest in WAIS, 'Kanahiroi" Test, Verbal Fluency and Wisconsin Card Sorting Test. In accordance with cerebral lesions on MRI, patients were divided into three groups. A: Multiple-confluent lesions, B: Discrete lesions, C: No lesion. In MS patients as a whole, performance of PAL, "Kanahiroi" Test and Verbal Fluency were significantly impaired compared with 10 age and education matched normal controls (p < 0.05), while other tests were not. In four out of five patients of A group, more than four neuropsychological tests showed below mean -2SD score of normal controls, whereas in patients of B and C group, less than three neuropsychological tests showed below -2SD score of normal controls. In conclusion, severity of cognitive impairment in patients with MS correlated with lesion extent on MRI. Patients with MS exhibited significant cognitive impairment on tasks of recent memory and mental processing speed. It is suggested that MS patients show the features of subcortical dementia.