Attentional control adjustments in Eriksen and Stroop task performance can be independent of response conflict.
In the Eriksen flanker and colour-word Stroop tasks, the response time (RT) difference between incongruent and congruent trials is smaller following incongruent trials than following congruent trials: the "Gratton effect" (Gratton, Coles, & Donchin, 1992). According to the prevailing conflict-monitoring theory (Botvinick, Braver, Barch, Carter, & Cohen, 2001), the Gratton effect reflects attentional control adjustment following response conflict on incongruent trials. However, because previous studies compared incongruent and congruent trials, it remains unclear to what extent the Gratton effect is driven by incongruent rather than congruent trials. To resolve this issue, we included neutral trials in addition to incongruent and congruent trials in the Eriksen (Experiment 1) and Stroop (Experiment 2) tasks. Participants responded manually and vocally in both tasks. Moreover, we assessed responding to Stroop stimuli that were preceded by neutral cues or by incongruent- or congruent-predicting cues (Experiment 3). In all three experiments, the RT difference between incongruent and congruent trials was larger for postcongruent trials than for postincongruent and postneutral trials. These findings suggest that control adjustments can be independent of response conflict, challenging conflict-monitoring theory.
Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Centre for Cognition, Postbus 9104, 6500 HE, Nijmegen, The Netherlands. m.lamers@donders.ru.nl
Martijn J M
MJ
Lamers
Ardi
A
Roelofs
D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D003220:Conflict, Psychological; D003463:Cues; D005260:Female; D006801:Humans; D007389:Internal-External Control; D008297:Male; D011930:Reaction Time / Q000502:physiology*; D057190:Stroop Test / Q000706:statistics & numerical data*; D013334:Students / Q000523:psychology; D013647:Task Performance and Analysis; D055815:Young Adult