Two experiments were conducted to determine the mechanism underlying the spacing effect in free-recall tasks. Participants were required to study a list containing once-presented words as well as massed and spaced repetitions. In both experiments, presentation background at repetition was manipulated. The results of Experiment 1 demonstrated that free recall was higher for massed items repeated in a different context than for massed items repeated in the same context, whereas free recall for spaced items was higher when repeated in the same context. Furthermore, a spacing effect was shown for words repeated in the same context, whereas an attenuated spacing effect was revealed for words repeated in a different context. These findings were replicated in Experiment 2 under a different presentation background manipulation. Both experiments seem to be most consistent with a model that combines the contextual variability and the study-phase retrieval mechanism to account for the spacing effect in free-recall tasks.

doi.org/10.1037/0278-7393.30.4.796, hdl.handle.net/1765/10790
Journal of Experimental Psychology: Learning, Memory, and Cognition
Department of Psychology

Verkoeijen, P., Rikers, R., & Schmidt, H. (2004). Detrimental Influence of Contextual Change on Spacing Effects in Free Recall. Journal of Experimental Psychology: Learning, Memory, and Cognition, 30(4), 796–800. doi:10.1037/0278-7393.30.4.796