Abnormality of Contingent Negative Variation Correlates with Parkinson's Disease Severity

We sought to assess the influence of Parkinson's disease (PD) on contingent negative variation (CNV).

This prospective study included 49 patients with PD (69.7±16.5; 35 male) and 35 age- and sex-matched controls. The PD cohort was subdivided, according to the Hoehn-Yahr Scale, Unified Parkinson's Disease Rating Scale (UPDRS), and UPDRS Part III, into 30 cases of uncomplicated PD and 19 cases of advanced PD. CNV was recorded over the frontal and central vertex with a linked bimastoid reference using a dual-stimulus paradigm with interstimulus intervals (ISIs) of 1.7 and 2.0 seconds.

In advanced PD, the amplitude of the late CNV over the central vertex was markedly reduced (p<0.005) at ISI of 1.7 seconds and correlated negatively with UPDRS (r=-0.32; p<0.003) and motor score (UPDRS Part III) (r=-0.45; p<0.002).

Late CNV amplitude was significantly abnormal in PD and correlated with the severity of the motor manifestations.