The bivalency effect: adjustment of cognitive control without response set priming

The occasional occurrence of bivalent stimuli, that is, stimuli with features relevant to two tasks, slows performance on subsequent tasks with univalent stimuli, including those which have no common features with bivalent stimuli (i.e., the "bivalency effect"). We have suggested that the bivalency effect might stem from an episodic context binding arising from the occasional occurrence of bivalent stimuli. However, as the same response set is used usually for univalent and bivalent stimuli, bivalent stimulus features may be negatively primed via response features. We investigated this possibility in two experiments, in which one group of participants used the same response keys for all tasks and another group used separate response keys. The results showed a comparable bivalency effect in both groups. Thus, it rather results from episodic context binding than from response set priming.