title: Dopaminergic modulation of performance monitoring in Parkinson's disease: An event-related potential study.
abstract: Monitoring one's actions is essential for goal-directed performance. In the event-related potential (ERP), errors are followed by fronto-centrally distributed negativities. These error(-related) negativity (Ne/ERN) amplitudes are often found to be attenuated in patients with Parkinson's disease (PD) compared to healthy controls (HC). Although Ne/ERN has been proposed to be related to dopaminergic neuronal activity, previous research did not find evidence for effects of dopaminergic medication on Ne/ERN amplitudes in PD. We examined 13 PD patients "on" and "off" dopaminergic medication. Their response-locked ERP amplitudes (obtained on correct [Nc/CRN] and error [Ne/ERN] trials of a flanker task) were compared to those of 13 HC who were tested twice as well, without receiving dopaminergic medication. While PD patients committed more errors than HC, error rates were not significantly modulated by dopaminergic medication. PD patients showed reduced Ne/ERN amplitudes relative to HC; however, this attenuation of response-locked ERP amplitudes was not specific to errors in this study. PD-related attenuation of response-locked ERP amplitudes was most pronounced when PD patients were on medication. These results suggest overdosing of dopaminergic pathways that are relatively spared in PD, but that are related to the generation of the Ne/ERN, notably pathways targeted on the medial prefrontal cortex.
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Caroline
authors.initials: C
authors.lastname: Seer
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Lange
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Loens
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Wegner
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schrader
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Dressler
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Dengler
authors.affiliation: Department of Neurology, Hannover Medical School, Hannover, Germany.
authors.forename: Bruno
authors.initials: B
authors.lastname: Kopp
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D004298:Dopamine / Q000502:physiology*; D018492:Dopamine Antagonists; D004569:Electroencephalography; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology*; D011597:Psychomotor Performance; D011930:Reaction Time
chemical_list: D000978:Antiparkinson Agents; D018492:Dopamine Antagonists; D007980:Levodopa; D004298:Dopamine