Long-term memory speeds encoding, independently of attention

Abstract

Recent studies suggest that familiar objects benefit from faster working memory (WM) encoding – the transformation of fragile perceptual representations into durable WM representations. This observation led contemporary WM models to postulate a long-term memory (LTM) “template-matching” mechanism, which speeds standard encoding processes. However, faster encoding may also be caused by higher attentional priority for familiar objects. In the current study, we examined whether LTM template matching can be dissociated from selective attention. We used a Rapid Serial Visual Presentation task and a manipulation previously shown to have no effect on attention. While the selection cue remained constant throughout the experiment, targets were either English or Hebrew letters, presented to native English-speakers and Hebrew-speakers. In Experiments 1 and 2, when the target was one of 16 letters, participants were more accurate when reporting target letters from their (familiar) native language relative to non-native language. In Experiment 2, the target was preceded by peripheral distractors which resulted in an “attentional blink” effect. Although a familiarity benefit was present for target accuracy, familiar and unfamiliar distractors produced an attentional blink effect of equal magnitude, demonstrating equal efficacy in capturing attention. In Experiment 3, a familiarity effect emerged even when the target language was blocked. This shows that the familiarity effect observed in Experiments 1 and 2 cannot be attributed to a response bias in favour of reporting one’s own language. Overall, the current study provides robust evidence that LTM template-matching speeds encoding of familiar items, independently of attention.