Distributed Practice

Distributed Practice

We retain information (such as classmates’ names) better when our encoding is distributed over time. More than 300 experiments over the last century have consistently revealed the benefits of this spacing effect (Cepeda et al., 2006). Massed practice (cramming) can produce speedy short-term learning and feel- ings of confidence. But to paraphrase pioneer memory researcher Hermann Ebbinghaus (1885), those who learn quickly also forget quickly. Distributed practice produces better long-term recall. After you’ve studied long enough to master the material, further study becomes inefficient (Rohrer & Pashler, 2007). Better to spend that extra reviewing time later—a day later if you need to remember something 10 days hence, or a month later if you need to remember something 6 months hence (Cepeda et al., 2008).
Spreading your learning over several months, rather than over a shorter term, can help you retain information for a lifetime. In a 9-year experiment, Harry Bahrick and three of his family members (1993) practiced foreign language word translations for a given number of times, at intervals ranging from 14 to 56 days. Their consistent finding: The longer the space between practice sessions, the better their retention up to 5 years later.

One effective way to distribute practice is repeated self-testing, a phenomenon that researchers Henry Roediger and Jeffrey Karpicke (2006) call the testing effect. In this text, for example, the Retrieval Practice features offer such an opportunity. Better to practice retrieval (as any exam will demand) than merely to reread material (which may lull you into a false sense of mastery).

The point to remember: Spaced study and self-assessment beat cramming and rereading.