REACTION-TIME AND INTELLIGENCE IN PATIENTS WITH OLIVOPONTOCEREBELLAR ATROPHY

Fifteen olivopontocerebellar atrophy (OPCA) patients and 15 normal subjects underwent simple and multiple-choice reaction time (RT) tasks of increasing difficulty, Raven's standard progressive matrices (Raven) and Pillon's 15 superimposed objects recognition test, The OPCA patients had lower scores than their control counterparts on all tests, In both groups, visual RT increased slowly with progressively difficult tasks whereas movement time (MT) showed a ceiling effect. RT is therefore independent of MT, being a measure of cognitive components. A strong correlation was noted in OPCA patients between RT and intelligence measured by Raven. In the control group, the correlation between RT and Raven was in the lower range, confirming data from the literature. There was no correlation with MT versus Raven in OPCA patients, whereas three MTs versus Raven were negatively correlated in control subjects. These findings represent additional evidence of the role of the cerebellum in cognitive thought.