Retrieval practice sometimes (shows) effects some 50 percent more than other forms of learning. In one study, one group of subjects read a passage four times. A second group read the passage just one time, but then the same group practiced recalling the passage three times.
But when the researchers followed up with both groups a few days later, the group that had practiced recalling the passage learned significantly more. In other words, subjects who tried to recall the information instead of rereading it showed far more expertise.
What’s important about retrieval practice is that people take steps to recall what they know. They ask themselves questions about their knowledge, making sure that it can be produced.
More concretely, retrieval practice isn’t like a multiple-choice test, which has people choose from a few answers, or even a Scrabble game, where you hunt in your memory for a high-point word. Retrieval practice is more like writing a five-sentence essay in your head: You’re recalling the idea and summarizing it in a way that makes sense.
As psychologist Bob Bjork told me, “The act of retrieving information from our memories is a powerful learning event.”
Ulrich Boser, Learn Better