Effects of aging, Parkinson's disease, and dopaminergic medication on response selection and control.
We examined effects of short-term and long-term dopaminergic medication in Parkinson's disease on conflict monitoring or response selection processes. These processes were examined using event-related potentials (ERPs), while subjects performed a stimulus-response (S-R) compatibility task. An extended sample of young and elderly controls, Parkinson's disease patients with a medication history (PDs) and initially diagnosed, drug-naïve de novo PD patients (de novo PDs) were enrolled. Both PD groups were measured twice (on and off-medication or before and 8 weeks after medication onset). The results show that dopaminergic intervention selectively reduced the pathologically enhanced response selection in compatible S-R relations. This medication effect was already evident after short-term treatment, not differing from long-term treatment and performance in elderly controls. Contrary, age-related attenuations of the N2 in incompatible S-R relations, probably reflecting impaired conflict processing or response control, are unaffected by medication. The results suggest that compatible and incompatible S-R relations demand different neuronal mechanisms within the basal ganglia, as only the former are affected by agonizing the dopaminergic system.
Willemssen
Rita
R
Leibniz Research Centre for Working Environment and Human Factors, WHO Collaborating Research Centre Dortmund, Germany.
Falkenstein
Michael
M
Schwarz
Michael
M
Müller
Thomas
T
Beste
Christian
C
D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D000978:Antiparkinson Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002755:Choice Behavior / Q000187:drug effects* / Q000502:physiology; D015259:Dopamine Agents / Q000494:pharmacology / Q000627:therapeutic use*; D004569:Electroencephalography / Q000379:methods; D005071:Evoked Potentials / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000188:drug therapy* / Q000503:physiopathology*; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D055815:Young Adult
D000978:Antiparkinson Agents; D015259:Dopamine Agents