A study on the background activities of EEG in Parkinson disease

To determine whether increased background activities in early-stage Parkinson disease (PD) contribute to a higher amplitude of P3 of event-related potentials, we characterized the alpha wave of background activity in Parkinson disease. Included in the study were 18 early-stage Parkinson disease patients without dementia and 17 age-matched patient controls without neurological disease. Visual inspection revealed increased amplitude, slower frequency, increased amount, and less occipital dominancy of alpha wave in Parkinson disease patients compared with controls. Amplitude spectra calculated with fast Fourier transform revealed slower occipital lead peak frequency in Parkinson disease patients. EEG findings in Parkinson disease without dementia demonstrated statistically significant differences from controls. Increased background activities possibly contribute to a higher amplitude of P3.