Auditory distraction eliminates retrieval induced forgetting: implications for the processing of unattended sound

The Retrieval-Induced Forgetting (RIF) paradigm includes three phases: (a) study/encoding of category exemplars, (b) practicing retrieval of a sub-set of those category exemplars, and (c) recall of all exemplars. At the final recall phase, recall of items that belong to the same categories as those items that undergo retrieval practice, but that did not undergo retrieval practice themselves, is impaired. The received view is that this is because retrieval of target category-exemplars (e.g., "Tiger" in the category Four-legged animal) requires inhibition of nontarget category-exemplars (e.g., "Dog" and "Lion") that compete for retrieval. Here, we used the RIF paradigm to investigate whether ignoring auditory items during the retrieval-practice phase modulates the inhibitory process. In two experiments, RIF was present when retrieval practice was conducted in quiet and when it was conducted in the presence of spoken words that were drawn from a different category to that from which the targets for retrieval practice were selected. In contrast, RIF was abolished when words that were either identical to, or merely semantically related to, the retrieval-practice words were presented as background speech. The results suggest that the act of ignoring speech can reduce inhibition of the non-practiced category-exemplars, thereby eliminating RIF, but only when the spoken words are competitors for retrieval (i.e., belong to the same semantic category as the to-be-retrieved items).