Does Working Memory Capacity Moderate the Interleaving Benefit?

Interleaving examples of different categories, rather than blocking examples by category, often enhances the learning of those categories, but does this benefit vary by learner? On one hand, it could be argued that interleaving places increased demands on a learner's working-memory capacity (WMC), which could foster suboptimal learning for those with lower WMC than for those with higher WMC. On the other hand, studies show that learners with higher WMC seem to process information in more effective ways, in which case lower-WMC learners may benefit more from interleaving than higher-WMC learners. To test these two hypotheses, across five studies, participants studied examples of perceptual categories (artists' styles) or text-based categories (non-parametric statistics) presented either blocked or interleaved. On a final test, participants classified new examples of the studied categories. We found a robust benefit of interleaving across both domains, but this benefit did not vary by WMC.