Neuropsychological performance in lateralized parkinsonism
K. B. Spicer, R. J. Roberts and P. A. LeWitt
Department of Psychology, Wayne State University, Detroit, MI 48202.
Seven dextral patients with Parkinson's disease (PD) who had predominant
right-sided motor signs were compared on neuropsychological tests with
eight dextral patients with PD who had predominant left-sided signs.
Objective criteria for group designation were developed from clinical
ratings. The patient subgroups were matched on age, education, estimated
premorbid IQ, severity of motor signs, and medication usage. Patients with
signs lateralized to the right were more impaired on tests of dominant
hemisphere function (serial digit learning, confrontation naming, and
verbal associative fluency), but no differences were found on tests of
nondominant hemisphere function (form sequence learning, line orientation,
facial recognition), indicating some correlation of neuropsychological
performance with lateralization of predominant motor signs. Findings
demonstrate that the cognitive deficits (particularly visuospatial)
previously reported in the literature are not seen consistently in all
subjects with PD.
