The Effect of Multisensory Distraction on Working Memory: A Role for Task Relevance?

There is growing recognition that working memory and selective attention are highly related. However, a key function of selective attention-ignoring distractors-is much less understood in the domain of working memory. In the attention domain, it is now clear that distractors' task relevance and stimulation of multiple senses at a time (i.e., being multisensory), affect how much such information can distract from the main task, and that load modulates these effects. Here, we examined the effects of the task relevance and multisensory nature of distractors on working memory performance under high and low memory load, aiming to clarify whether distracting information similarly affects selective attention performance and working memory performance. We proposed a multiexperiment research plan involving up to three consecutive experiments, based on an initial online study (Experiment 0) with fully task-irrelevant distractors. There, we found conclusive evidence against a difference in how unisensory and multisensory distractors affected working memory performance. The next study, Experiment 1, replicated these results. However, when distractors were made partly task relevant in the subsequent Experiment 2d, multisensory distractors disrupted working memory performance more than unisensory distractors on average. However, closer nonpreregistered inspection revealed that multisensory distractors were actually only more disruptive than auditory distractors, and similarly as disruptive as visual distractors. Thus, overall, there was no strong evidence for multisensory distractors being more disruptive to working memory performance than unisensory distractors. Taken together, these experiments constitute a novel and detailed investigation of the impact of distracting information on working memory performance.