How to present exemplars of several categories? Interleave during active learning and block during passive learning

How to present exemplars of several categories? Interleave during active learning and block during passive learning Paulo F. Carvalho (pcarvalh@indiana.edu) Department of Psychological and Brain Sciences, Indiana University 1101 E. Tenth St., Bloomington, IN 47405 USA Robert L. Goldstone (rgoldsto@indiana.edu) Department of Psychological and Brain Sciences, Indiana University 1101 E. Tenth St., Bloomington, IN 47405 USA Abstract Research on how information should be presented during inductive category learning has identified both interleaving of categories and blocking by category as beneficial for learning. Previous work suggests that this mixed evidence can be reconciled by taking into account within- and between- category similarity relations. In this paper we present a new moderating factor. One group of participants studied categories actively, either interleaved or blocked. Another group studied the same categories passively. Results from a subsequent generalization task show that active learning benefits from interleaved presentation while passive learning benefits from blocked presentation. Keywords: interleaving; blocking; learning; comparison Introduction Can the method with which information is presented substantially affect learning? The answer seems to be “yes.” Changing the way with which information is presented not only changes what is learned (Schyns, Goldstone, & Thibaut, 1998) but also how well it is learned (Goldstone, 1996). One example is the order in which instances are presented in a study session and the effect this has for inductive learning. Kornell and Bjork (2008) demonstrated that if participants are given study examples of paintings from several artists’ interleaved, participants’ later memory and generalization is substantially improved when compared to presenting each artist in a separate block. The advantage of interleaving over blocking for inductive learning has been repeatedly shown in recent years. Interleaving of categories has been shown to improve learning of naturalistic materials for both young and older adults (Kornell, Castel, Eich, & Bjork, 2010; Wahlheim, Dunlosky, & Jacoby, 2011), as well as flashcard learning (Kornell, 2009). It has also been demonstrated in children (Vlach, Sandhofer, & Kornell, 2008; Vlach & Sandhofer, Notwithstanding the clear benefit of interleaving in some situations, there have also been demonstrations of the advantage of blocking for category learning. For example, Goldstone (1996) presented participants with complex images consisting of 20 line segments. There were two conditions: frequent alternation of categories (interleaving) and infrequent alternation (blocking). The results showed that participants were better at learning the categories in the infrequent alternation condition. The author associates this advantage with the relative difficulty in finding the common features shared by members of each category (for further evidence of blocking advantages using different kinds of tasks and stimuli see Kurtz & Hovland, 1956; Whitman & Garner, 1963). Given this mixed evidence about the best way to sequentially present information for optimal learning, an important question is: what conditions yield an advantage for interleaving compared to blocking? This question has received some attention in recent years. For instance, Carvalho and Goldstone (2012) showed that when studying low similarity categories, blocked presentation resulted in improved subsequent generalization performance. This pattern was reversed for high similarity categories (for similar results with category discriminability, see Zulkiply & Burt, 2013). Carvalho and Goldstone (2012; see also Goldstone, 1996) have proposed that interleaving categories allows participants to identify the features that distinguish between the categories, while blocked presentation promotes the identification of features that are characteristic among stimuli within a single category. This dichotomy is the result of the same principle: the selective emphasis of categorization-relevant features during comparison of sequentially presented objects. In the case of interleaved presentation, differences between objects belonging to different categories will be emphasized while for blocked presentation, similarities among objects belong to the same category will be emphasized. This same process will result in improved or hindered learning depending on whether similarities or differences need to be learned. One possible way in which category learning could move from an emphasis on differences towards an emphasis on similarities is by changing the similarity relations within and between categories (Carvalho & Goldstone, 2012; Zulkiply and Burt, However, the characteristics of the categories being studied are not the only factors that can have an influence on how sequential comparison impacts learning. In theory, any property of the learning situation that changes attentional constraints could have similar impact by changing the task