Cognitive and affective functioning in Parkinson's disease patients with lateralized motor signs.

Eleven patients with Parkinson's disease (PD) and predominantly right-sided motor signs, 12 patients with PD and predominantly left-sided signs, and 11 demographically matched healthy controls were compared on tests assessing a range of cognitive and affective functions. Assuming a novel approach, our test battery was composed of measures drawn from ones previously used in the hemiparkinson' s disease and lateralized PD literature. The two patient groups were similar in illness duration, severity of motor signs, and degree of lateralized motor deficits. Statistical analyses did not reveal significant differences between patient groups, consistent with other studies that have failed to find differences in neuropsychological functioning between PD patients with right- and left-sided motor signs.