QUANTITATIVE EEG CHANGES IN NONDEMENTED PARKINSONS-DISEASE PATIENTS BEFORE AND DURING L-DOPA THERAPY

Nineteen non-demented Parkinson's disease patients have been studied b efore and during L-dopa therapy by quantitative EEG performed at rest with eyes closed (EC) and during attentive (BR) and cognitive (FIX) ta sks. The data have been compared by ANOVA analysis with those of 22 ag e-matched healthy subjects. In all three conditions a significant incr ease of the mean delta power as well as a decrease of beta 1 power was observed in patients before therapy. Abnormal high delta values were observed in 10 out of 19 patients. L-Dopa therapy did not modify this EEG pattern. After therapy, however, a significant decrease of reactiv ity to BR and FIX was observed in patients compared to normal subjects , These data confirmed the presence of an EEG synchronization (increas e of slow activity and decrease of fast activity) in non-demented Park inson's disease patients, This pattern, similar to that of subjects wi th Alzheimer-type dementia, might indicate an intellectual impairment at sub-clinical level. A non-dopaminergic mechanism could be responsib le for this impairment.