Making accurate predictions of future memory performance (Judgements of Learning; JOLs) is a prerequisite for efficient learning. Since decades, those JOLs are assumed to be made inferentially, based on cues. This cue-utilization approach substituted the idea that JOLs are directly linked to memory quality. We criticize the reasons for the rejection of this memory-strength hypothesis because they ignore the existence of two different memory systems: working memory which holds representations immediately accessible, and long-term memory which is a more permanent store. Considering both memory systems, the current work revisited the memory-strength hypothesis: In Experiment 1, participants memorized sequences of two or four colored objects, then they provided JOLs for a long-term memory test, and performed a working memory test on the objects’ colors. After learning 200 objects, the long-term memory test on all studied objects followed. Sequence-length affected working memory, but not long-term memory performance. JOLs, however, were higher for sequences of two than four and correlated higher with working memory than long-term memory performance. Experiment 2 replicated the sequence-length effect on JOLs in the absence of a working memory test. Results of a sequence-eight condition revealed an increase in JOLs’ accuracy when the number of studied objects exceeded working memory span. Contrary to predominant theories, our findings suggest that JOLs are based on the quality of memory representations.
Where working memory meets long-term memory: The interplay of list length and distractors on memory performance.