Abstract:Using 5 experiments, the authors explored the dependency of spacing effects on rehearsal patterns. Encouraging rehearsal borrowing produced opposing effects on mixed lists (containing both spaced and massed repetitions) and pure lists (containing only one or the other), magnifying spacing effects on mixed lists but diminishing spacing effects on pure lists. Rehearsing with borrowing produced large spacing effects on mixed lists but not on pure lists for both free recall (Experiment 1) and recognition (Experiment 2). In contrast, rehearsing only the currently visible item produced spacing effects on both mixed lists and pure lists in free recall (Experiment 3) and recognition (Experiment 4). Experiment 5 demonstrated these effects using a fully within-subjects design. Rehearse-aloud protocols showed that rehearsal borrowing redistributed study from massed to spaced items on mixed lists, especially during massed presentations. Keywords: rehearsal, spacing effect, long-term memory, list strength effect, output interference
Article:An important question in memory research is how people process repetitions of the same item on multiple occasions. Repeated items may occur either immediately in succession (called massed repetitions) or with other items intervening between them (called spaced repetitions). The memory advantage of spaced repetitions over massed repetitions is well known and is termed the spacing effect. The spacing effect has been widely replicated by researchers, using many different memory tests, under both incidental and intentional encoding conditions (for reviews, see Dempster, 1996;Greene, 1989;Raaijmakers, 2003; for meta-analyses, see Donovan & Radosevich, 1999;Janiszewski, Noel, & Sawyer, 2003). However, a complete explanation of the cause of the spacing effect has remained elusive.The current article is focused on the importance of rehearsal borrowing in spacing effect studies. Our studies were not designed to argue that rehearsal is the cause of spacing effects but rather to examine how rehearsal instructions affect the magnitude of the spacing effect in different types of designs. Specifically, we suggest that the most commonly used rehearsal strategy has different effects on pure-list and mixed-list spacing designs.
