Reading: Cramming or Spacing?

A Is it better to study a little at a time, or to leave all the work until just before a test? Researchers have investigated this question by comparing spacing, in which learning events are spread out in time, with massing, in which they are packed together. In 2006, Cepeda, Pashler, Vul, Wixted and Rohrer published a review of distributed practice in verbal recall tasks in Psychological Bulletin. They gathered 839 assessments of distributed practice from 317 experiments, reported in 184 articles. Among other things, the review compared presentations that follow each other directly with learning episodes separated in time, and it compared shorter separations, called lag, with longer ones.

B The same review also asked how the length of the gap between study sessions affects memory. The gap that produced the strongest memory on the final test grew longer as the delay before the final test grew longer. Put simply, the best gap is longer for a learner who must remember something for a long time than for a learner who needs it only for a short time.

C In 2009, Kornell published a study in Applied Cognitive Psychology. He opened by noting that hundreds of experiments support the benefit of spacing, yet this benefit is not well known among teachers and students. He tested it in a realistic setting, flashcards, pointing out that learners often split their cards into several small stacks, even though a small stack leaves less time between study trials than a large one. In three experiments, participants used an online study program to learn word pairs. One large stack produced better results than four smaller stacks studied separately, which counts as massing. Spacing also beat cramming, which Kornell defines as massing study on the last day before the test. In the experiments overall, 90% of the participants did better with spacing than with massing. After their first study session, however, 72% of them believed that massing had been the better method.

D In 2013, Dunlosky, Rawson, Marsh, Nathan and Willingham evaluated 10 learning techniques in Psychological Science in the Public Interest. Practice testing and distributed practice were given high utility assessments, since both help learners of different ages and abilities and both improve performance on many kinds of task. Three techniques received moderate utility assessments, and five, among them rereading and highlighting, received low ones. The authors note that students report relying heavily on rereading and highlighting. Yet neither technique reliably improves performance, so they advise using other techniques instead, for example practice testing in place of rereading. A note of caution: Cepeda and colleagues reviewed verbal recall tasks, and Kornell's participants learned word pairs, so this evidence concerns verbal material and not every kind of learning.