On the (elusive) role of oral motor-movements in fluency-based memory illusions

It is well established that the ease with which a stimulus is processed affects many different types of evaluative judgments. Recently, it has been proposed that for verbal stimuli the effect of fluency on such judgments is mediated by the muscles that are involved in speech (Topolinski & Strack, 2009, 2010). Evidence for this claim can be found in studies that have shown that fluency effects are eliminated if such judgments are made while these muscles are otherwise engaged (such as while chewing gum or eating). Additional research has found that oral-motor tasks block familiarity-based responding on recognition memory tasks (Topolinski, 2012). The current study investigated the effect of an oral-motor task on recognition memory. Of particular interest was whether the fluency-blocking effects of an oral-motor task would extend to fluency-based illusions of recognition memory. Although we found robust fluency-based illusions of familiarity, we did not find that the effects were modulated by the nature of the concurrent task (gum-chewing vs. a manual-motor task). Moreover, we found no evidence that oral-motor tasks affected recognition more generally, nor did we find that an oral-motor task modulated affective ratings to repeated stimuli. We were also unable to replicate the finding that an oral-motor task blocks the false fame effect (Topolinski & Strack, 2010). These results call into question the assertion that oral-motor movements mediate fluency effects in recognition memory and other evaluative judgments.