Self-regulated learning of a natural category: do people interleave or block exemplars during study?

Despite decades of research focused on the representation of concepts, little is known about the influence of self-regulatory processes when learning natural categories. Such work is vital, as many contexts require self-regulation when we form complex concepts. Previous research has demonstrated that interleaving, as compared to blocking, can improve classification. Thus, as an initial step to explore self-regulated learning of natural concepts, we evaluated whether people chose to block or interleave their practice. According to the search-for-differences hypothesis, people attempt to identify features of birds that distinguish one category (i.e., bird family) from another, and hence should interleave their study. According to the search-for-similarities hypothesis, people attempt to identify features that indicate inclusion into a single category, and hence are expected to block their study. To evaluate these hypotheses, we had participants learn exemplar birds (e.g., Song Sparrow) with their respective bird families (e.g., Sparrow) by selecting the order in which to study bird families. Across four experiments, different formats for selecting exemplars for study were used, so as to provide converging evidence for how participants regulated their learning. Participants overwhelmingly preferred to block their study, even though interleaving is normatively better for learning.