Duthoo, W. 1 , Wühr, P. 2 & Notebaert, W. 1
1 Department of Experimental Psychology. Ghent University. Ghent, Belgium.
2 Institut für Psychologie. Technische Universität Dortmund. Dortmund, Germany.
In two series of studies, the role of expectations in cognitive control was put to the test. Going back to the original interpretation of the congruency sequence effect (Gratton, Coles, & Donchin, 1992), we sought evidence for a congruency repetition bias steering attentional control. In a first experiment, we investigated how participants’ explicit predictions influenced subsequent Stroop performance. Similar to the fallacious hot hand belief in gambling, subjects overpredicted repeating stimulus events. Moreover, behavioural adjustments (i.e., a Gratton effect) were only found when subjects predicted a congruency repetition, whereas alternation predictions did not impact the Stroop effect. In a following series of studies, we manipulated expectations more implicitly. Therefore, we compared two Stroop conditions in which the amount of either congruency repetitions or congruency alternations was raised. Only in the repetition condition a Gratton effect was found, which disappeared completely when alternations outnumbered repetitions. Taken together, these findings point out the importance and validity of expectancy-based proactive control. Therefore, we propose that repetition expectancy is a variable that should be given more attention in current theorizing and modelling of cognitive control, which is characterized by an emphasis on reactive, conflict-induced control adjustments.