Implicit misattribution of evaluative responses: contingency-unaware evaluative conditioning requires simultaneous stimulus presentations.

Recent research has shown that evaluative conditioning (EC) procedures can change attitudes without participants' awareness of the contingencies between conditioned and unconditioned stimuli (Hütter, Sweldens, Stahl, Unkelbach, & Klauer, 2012). We present a theoretical explanation and boundary condition for the emergence of unaware EC effects based on the implicit misattribution of evaluative responses from unconditioned to conditioned stimuli. We hypothesize that such misattribution is only possible when conditioned and unconditioned stimuli are perceived simultaneously. Therefore we manipulate the simultaneity of the stimulus presentations and apply a process dissociation procedure to distinguish contingency-aware from contingency-unaware EC effects. A multinomial model indicates that with sequential presentations, EC effects do not occur without contingency awareness. However, unaware EC effects do occur with simultaneous presentations. The findings support dual-process theories of learning.