Freeing capacity in WM through the use of LTM representations

Abstract

Previous research indicates that LTM may contribute to performance in working memory (WM)tasks. Across three experiments we investigate the extent to which active maintenance in WM can bereplaced by relying on information stored in episodic LTM, thereby freeing capacity for additionalinformation in WM. First, we presented participants with word pairs to encode into LTM, followed by aWM task, also involving word pairs. Crucially, the pairs presented in each WM trial comprised varyingnumbers of new pairs and the previously learned LTM pairs. Experiment 1 showed that recallperformance in the WM task was unaffected when memory set size increased through the addition ofLTM pairs, but that it deteriorated when set size increased through adding new pairs. In Experiment 2 weinvestigated the robustness of this effect, orthogonally manipulating the number of new and LTM pairsused in the WM task. Performance declined with the addition of LTM pairs for low WM load, but wasstill superior to performance with the same set size of only new pairs. By contrast, adding LTM pairs didnot affect recall performance at higher WM load. In Experiment 3 we show that the benefit of LTMrepresentations arises from retrieving these at (WM) test, leading them to suffer from typical interferenceeffects. We conclude that individuals can outsource workload to LTM to optimise performance, and thatthe WM system possesses a gate to LTM that can be opened or closed depending on the current memoryload.

The influence of long-term memory on working memory: Age-differences in proactive facilitation and interference

“…Using a Hebb repetition paradigm with letters and words, Mizrak and Oberauer (2020) found evidence of proactive facilitation and no evidence of interference. On the other hand, two studies using cued recognition have found evidence of interference from previously learned associations (word pairs in Bartsch & Shepherdson, 2020;and image-word pairs in Hoskin et al, 2018). Bartsch and Shepherdson (2020) suggest that recognition may lead to greater competition at test relative to cued recall, in particular when the previously learned associate is presented as a lure, which may explain differences in findings.…”

“…On the other hand, two studies using cued recognition have found evidence of interference from previously learned associations (word pairs in Bartsch & Shepherdson, 2020;and image-word pairs in Hoskin et al, 2018). Bartsch and Shepherdson (2020) suggest that recognition may lead to greater competition at test relative to cued recall, in particular when the previously learned associate is presented as a lure, which may explain differences in findings. To our knowledge, the generalizability of Oberauer et al's (2017) specific findings to other materials has not been addressed.…”

“…Oberauer et al (2017) acknowledge that their findings may be limited to the particular task they chose, which was fine-grained color recall cued by object. Other studies have addressed similar questions regarding the interaction of long-term and working memory with different materials and tasks (Bartsch & Shepherdson, 2020;Hoskin, Bornstein, Norman, & Cohen, 2018;Mizrak & Oberauer, 2020), and findings have been mixed. Using a Hebb repetition paradigm with letters and words, Mizrak and Oberauer (2020) found evidence of proactive facilitation and no evidence of interference.…”