The optimal sequence for learning can depend on one's strategy: An individual differences approach

Category learning promotes multiple cognitive processes including memorization and induction (e.g., rule finding). Individuals can differ in their reliance on a given process. Would optimal study sequence (interleaving vs. blocking) depend on that process (memorization vs. rule-finding)? Interleaving examples from a category can be better than blocking when the test necessitates similarity-based classification, but blocking examples from a given category can be better when the test necessitates rule-based classification. In three experiments, participants studied letter strings interleaved or blocked. Then they classified transfer items for which similarity-based classification would oppose rule-based classification. In Experiments 1a/1b, participants chose (and self-reported) their learning strategy. In Experiment 2, strategy was instructed. Memorizers (self-reported and instructed) had better similarity-based classification when items were interleaved than when they were blocked, but rule-abstractors (self-reported and instructed) had better rule-based classification when items were blocked than when they were interleaved. These results have implications for educational contexts. In educational settings, students need to categorize information. From figuring out what formula applies to a given physics problem to learning how to categorize plants in biology to picking out common themes in a literature course, categorization is a necessity. However, people differ in the strategies that they use to learn, with some trying to find rules and some focusing on memorization; these differences in strategy lead to differences in how people classify items. The present results showed that for memorizers, interleaving was more effective for similarity-based classification than was blocking, but for rule-abstractors, blocking was better for rule-based classification than was interleaving. Although the materials in the present studies were relatively simplistic, we argue that these findings could be used to make predictions about learning with educational materials and in educational settings. Teachers should be aware that two individuals could approach a task with qualitatively distinct strategies, so they should clarify their learning goals and sequence learning material in a way that optimizes learning. • Individuals differ in their learning strategies, with some focusing on memorization and some focusing on finding rules. • Interleaving tends to be effective for memory-based learning; blocking tends to be effective for rule-based learning. • We predicted that—in a single task—the advantage of interleaving versus blocking would depend on a learner's strategy. • The present results showed that the optimal sequence for learning depends on one's strategy.