title: Stimulus ambiguity elicits response conflict.
abstract: Conflict monitoring theory [M.M. Botvinick, T. Braver, D. Barch, C. Carter, J.D. Cohen, Conflict monitoring and cognitive control, Psychol. Rev. 108 (2001) 625-652] assumes that perceptual ambiguity among choice stimuli elicits response conflict in choice reaction. It hence predicts that response conflict is also involved in elementary variants of choice reaction time (RT) tasks, i.e., those variants that, by contrast with the Stroop task or the Go/No-Go task for instance, are rarely associated with cognitive control. In order to test this prediction, an experiment was designed in which participants performed a simple RT task and a regular between-hand 2-choice RT task under three different levels of stimulus ambiguity. The data show that response conflict, as measured by the N2 component of the event-related brain potential (ERP), was elicited in the 2-choice RT task but not in the simple RT task and that the degree of response conflict in the 2-choice RT task was a function of stimulus ambiguity. These results show that response conflict is also present in a regular choice RT task which is traditionally not considered to be a measure of cognitive conflict.
authors.affiliation: Department of Experimental Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium. arnaud.szmalec@UGent.be
authors.forename: Arnaud
authors.initials: A
authors.lastname: Szmalec
authors.forename: Frederick
authors.initials: F
authors.lastname: Verbruggen
authors.forename: André
authors.initials: A
authors.lastname: Vandierendonck
authors.forename: Wouter
authors.initials: W
authors.lastname: De Baene
authors.forename: Tom
authors.initials: T
authors.lastname: Verguts
authors.forename: Wim
authors.initials: W
authors.lastname: Notebaert
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D002755:Choice Behavior / Q000502:physiology*; D003220:Conflict, Psychological; D004193:Discrimination Learning / Q000502:physiology*; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation; D004569:Electroencephalography / Q000379:methods; D004585:Electrooculography / Q000379:methods; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D005795:Generalization, Stimulus / Q000502:physiology*; D006801:Humans; D008297:Male; D011930:Reaction Time / Q000502:physiology; D013647:Task Performance and Analysis