Interleaved Pretesting Enhances Category Learning and Classification Skills

Alternating between concepts during learning (interleaving) and making guesses about to-be-learned information before viewing the correct answers (pretesting) can enhance learning relative to focusing on one concept at a time (blocking) and studying, respectively. We investigated the potential benefits of interleaving and pretesting for acquiring categorical knowledge and classification skills. In three experiments, participants learned about psychopathological disorders from interleaved or blocked case studies and via pretesting or studying. A 5-min delayed test (Experiment 1) showed that interleaving and pretesting improved the ability to classify new and previously viewed case studies. Moreover, their combination had at least additive effects, yielding the best overall performance. Similar results occurred on a 48-hr delayed test (Experiment 2) and under conditions of equivalent time on task (Experiment 3). Overall, this study reveals that an effective scheduling approach paired with a beneficial learning activity forms a potent combination (interleaved pretesting) that is uniquely capable of enhancing learning.