Event-related potentials in Parkinson's disease: a 12-month follow-up study.

Auditory event-related potentials were recorded using the oddball paradigm in 26 patients with Parkinson's disease, all treated with L-Dopa. The latency of the P3 wave was significantly greater than in an age-matched controls, and was also correlated with the disease duration, but not with scores on two scales measuring cognitive deficit. One year later, when treatment with a dopaminergic agonist, bromocriptine 20-30 mg/day, had been added to the therapeutic regimen, N2 and P3 latencies had increased, whereas several clinical parameters had improved. Thus a longer P3 latency does not seem to be linked to a global cognitive deficit. The use of neuropsychological tests exploring more limited tasks should show the prospective utility of event-related potentials in Parkinson's disease.