Persistence of the spacing effect in incidental free recall: The effect of external list comparisons and intertask correlations

Abstract

The attenuation-of-attention explanation of the spacing effect was tested, using an incidental learning paradigm. The incidental task was one in which subjects rated each item on either one or two scales. When two scales were used, all repeated items (massed and distributed) were rated on both scales. In Experiment 1, each point on the rating scale was labeled with an exemplar, and subjects were asked to compare each list item with the given exemplars. In Experiment 2, the correlation between the two scales was systematically varied. Neither manipulation reduced the magnitude of the spacing effect.