Cognition and laterality in untreated hemiparkinsonism

Abstract

Twelve patients with idiopathic Parkinson's disease on only one side of the body were studied using various tests evaluating cognitive, memory, and psychomotor functions. All patients were untreated. The affected side was associated with impaired performance in motor and psychomotor tests but not in most of the tests to evaluate general cognitive capacity (WAIS) and memory (WMS). Patients with left hemiparkinsonism performed less well in the Picture Completion test of the WAIS and in the Stroop test (parts 3 and 3-2) than did subjects with right hemiparkinsonism. The results were interpreted as supporting the view that dopaminergic structures predominantly of the right hemisphere may be involved in the attention/activation process.