Contingent negative variation and movement-related cortical potentials in parkinsonism.

The contingent negative variation (CNV) and movement-related cortical potentials (MRCPs) were recorded in 10 cases of Parkinson's disease, 10 cases of vascular parkinsonism and 10 age-matched healthy controls. The amplitude of the early CNV was smaller in the Parkinson's disease group and the vascular parkinsonism group than in the healthy control group. The latencies of Bereitschaftspotential (BP) and negative slope (NS') were longer and the amplitude of BP was smaller in the Parkinson's disease group and the vascular parkinsonism group than in the healthy control group. These abnormalities in CNV and MRCPs were improved by intravenous injection of L-DOPA.