Performances of multiple sclerosis patients in tasks requiring language and visuoconstruction. Assessment of outpatients in quiescent disease stages.

In a group of 39 multiple sclerosis (MS) patients with at least average intelligence quotients (IQ), performances were examined in tests requiring language usage and figure copying. Numbers of correct, digressive and erroneous responses were analysed and compared with those obtained in 24 healthy volunteers, matched to the patients group for socio-economic status. The examined specific tasks yielded no additional contribution to the prevalence estimation of cognitive deterioration (18%), as based on an assessment of general intelligence. Linguistic or cognitive-constructional problems were no more severe or more frequent in MS patients than those in control subjects. Upon writing or copying figures, pencil stroke and pencil pressure were deficient. Speed of reading aloud and of colour naming was decreased in the MS group, the most probable explanation being impaired control of the phonatory apparatus, oculomotor problems or weakness of colour vision. Decreases in speed of performance are not necessarily of cognitive origin. Differences between the present and previous reports based on similar tasks, appear to be connected partly with differences in patient selection. Of the present group, all MS patients were in quiescent disease stages, depression was mild or absent and physical handicap was less than in most studies reporting definite specific deficits.