Adjustments of conflict monitoring in Parkinson's disease.
OBJECTIVE
In Stroop-like tasks, the detection of conflict triggers adjustments of cognitive control to reduce conflict in subsequent trials. The present study tested the hypothesis of an impaired modulation of conflict monitoring in Parkinson's disease (PD).


METHODS
18 PD patients and 18 healthy control (HC) participants performed a Stroop-like task in 2 conditions differing in terms of incongruent/congruent stimuli ratio.


RESULTS
HC participants demonstrated a sustained modulation of interference effect, the interference effect being decreased when the proportion of incongruent stimuli was high. A trial-by-trial analysis also showed that in the HC group, processing an incongruent stimulus reduced interference in the subsequent trial. Unlike controls, PD patients did not demonstrate any transient or sustained reduction of the interference effect.


CONCLUSIONS
Within the framework of recent models, these results can be interpreted as an impairment of a proactive mode of cognitive control in patients with PD.
Bonnin
Camille A
CA
Research Center on Cognition and Learning, University of Poitiers, France.
Houeto
Jean-Luc
JL
Gil
Roger
R
Bouquet
Cédric A
CA
D000223:Adaptation, Psychological / Q000502:physiology*; D000368:Aged; D001288:Attention / Q000502:physiology; D016022:Case-Control Studies; D003220:Conflict, Psychological; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000503:physiopathology* / Q000523:psychology*; D010364:Pattern Recognition, Visual; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D013223:Statistics as Topic