Sixty-seven parkinsonian patients and 44 control subjects were tested for cognitive function and motor performance, using reaction times and movement times. Parkinsonian subjects did significantly worse in tests that required visuoperceptual and perceptual motor abilities, such as Object Assembly, Block Design, and Zazzo's test. Analysis of covariance of test scores showed that Block Design and Object Assembly scores were not significantly different between patients and controls when adjusted for reaction and movement times. Also, reaction and movement times were more delayed in parkinsonian patients than in controls. These results stress the main role of motor dysfunction in visuospatial and perceptual motor impairment.