Chapter 12 Further Reading: Desirable Difficulties

Foundational Research

Bjork, R. A. (1994). Memory and metamemory considerations in the training of human beings. In J. Metcalfe & A. Shimamura (Eds.), Metacognition: Knowing about knowing. MIT Press. The paper where Bjork lays out the desirable difficulties framework most clearly. Academic but accessible. Essential reading if you want the primary source for this chapter's core ideas.

Bjork, E. L., & Bjork, R. A. (2011). Making things hard on yourself, but in a good way: Creating desirable difficulties to enhance learning. In M. A. Gernsbacher et al. (Eds.), Psychology and the Real World. Worth Publishers. A more accessible chapter-length treatment of desirable difficulties written for a broader audience. Good starting point if you want the framework without diving into primary research papers.

Slamecka, N. J., & Graf, P. (1978). The generation effect: Delineation of a phenomenon. Journal of Experimental Psychology: Human Learning and Memory, 4(6), 592–604. The original generation effect paper. Compact and readable. The methodology is simple enough that you can mentally replicate the experiment as you read it.

Books

Brown, P. C., Roediger, H. L., & McDaniel, M. A. (2014). Make It Stick: The Science of Successful Learning. Harvard University Press. The best popular account of the desirable difficulties research, written by researchers who conducted much of the foundational work. Highly readable, full of concrete examples. If you read only one book in this list, this is it.

Kornell, N., & Bjork, R. A. (2008). Learning concepts and categories: Is spacing the "enemy of induction"? Psychological Science, 19(6), 585–592. A research paper rather than a book, but central enough to the chapter's argument to belong here. Kornell and Bjork demonstrate that interleaving improves category learning even when it reduces performance during training — a key piece of evidence for why desirable difficulties produce learning that comfortable practice does not.

Research Papers

Richland, L. E., Kornell, N., & Kao, L. S. (2009). The pretesting effect: Do unsuccessful retrieval attempts enhance learning? Journal of Experimental Psychology: Applied, 15(3), 243–257. The definitive study on pre-testing. Richland and colleagues show that attempting to retrieve information before studying enhances learning of that information even when the attempts fail. Direct evidence for the "generate-wrong-answer" principle.

Kornell, N., Hays, M. J., & Bjork, R. A. (2009). Unsuccessful retrieval attempts enhance subsequent learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 35(4), 989–998. Complementary to the Richland study — focuses on the mechanism by which failed retrieval attempts enhance learning. If you want to understand why wrong answers before correct information helps, this paper is the place to look.

Lee, T. D., & Magill, R. A. (1983). The locus of contextual interference in motor skill acquisition. Journal of Experimental Psychology: Learning, Memory, and Cognition, 9(4), 730–746. A classic motor learning study demonstrating the contextual interference effect — the motor skill analog of interleaving and variation. Shows that variable, interleaved practice conditions produce better transfer to novel conditions than constant, blocked practice, even when performance during training is worse.

Accessible Articles

"Making It Stick" — various interviews and talks by Robert Bjork (freely available on YouTube) Bjork's public talks are excellent — clear, engaging, and full of practical applications. A search for "Robert Bjork desirable difficulties" will turn up several lecture recordings that cover the framework well.

Learning Scientists — "Six Strategies for Effective Learning" (learningscientists.org) The Learning Scientists have created well-designed summaries of the desirable difficulties research, including downloadable guides and classroom applications. Their treatment of spacing, retrieval practice, interleaving, and elaboration is grounded in the same research tradition as this chapter.

For Skeptics

Rowland, C. A. (2014). The effect of testing versus restudy on retention: A meta-analytic review of the testing effect. Psychological Bulletin, 140(6), 1432–1463. A comprehensive meta-analysis of the testing/retrieval practice effect. If you want the quantitative evidence for how large these effects actually are across many studies, this paper provides it. The effects are substantial and consistent.

Kornell, N. (2009). Optimizing learning using flashcards: Spacing is more effective than cramming. Applied Cognitive Psychology, 23(9), 1297–1317. A study that compares spaced and massed flashcard practice directly. The effects are large, replicable, and directly applicable to self-regulated learning. Useful for grounding the "spacing is better than cramming" claim in specific experimental evidence.