What retrieval practice is
It is any study method where you produce the answer and do not look at it. A flashcard you answer before you turn it. A practice test. A blank page on which you write all that you remember from a chapter.
The opposite is restudy: reading the text again, reading your notes again, looking at highlighted lines. Restudy puts the material in front of you. Retrieval makes you find it.
The testing effect is the name of the result: a test is not only a measurement of memory. The act of recall changes the memory and makes it last.
What the studies found
| Year | Study | What it found |
|---|---|---|
| 2006 | Roediger and Karpicke, Psychological Science | Students read a text, then read it again or tried to recall it. Rereading won on a test five minutes later. Recall won two days and one week later. |
| 2008 | Karpicke and Roediger, Science | Students learned 40 word pairs in Swahili. Those who kept testing themselves on all pairs recalled about 80 percent a week later. Those who stopped testing a pair once they got it right recalled about 35 percent. |
| 2011 | Karpicke and Blunt, Science | Recall practice beat drawing concept maps on a test a week later, even when the test itself was a concept map. The students had predicted the opposite. |
| 2013 | Dunlosky and others, Psychological Science in the Public Interest | A review of ten study techniques. Practice testing and spaced practice were rated high in usefulness. Highlighting, rereading and summarizing were rated low. |
| 2014 | Rowland, Psychological Bulletin | A meta-analysis of the testing effect. Across the studies, testing beat restudy by about half a standard deviation. |
Why it feels worse than it works
Rereading is smooth. The words are familiar, and familiar feels like known. Recall is rough. You search, you fail on some items, and that feels like not knowing.
The feeling points the wrong way. In the 2006 study, the rereading group was more confident about a later test, and the recall group did better on it. In the 2011 study, students predicted that concept maps would work better than recall, and the result was the reverse.
Robert Bjork calls this kind of effort a desirable difficulty: a condition that makes study harder now and memory stronger later.
How to use it
- Ask before you look. Cover the answer and say it or write it. Then check.
- Fail, then check. A wrong attempt followed by the right answer still helps. Feedback is the part you must not skip.
- Keep testing what you know. In the 2008 study, the items that students stopped testing were the items they lost.
- Space the tests. A recall the next day is worth more than a second recall one minute later.
How Axo uses it
Every Bite in Axo ends in five questions and not in a summary. XP comes only from an answer you recalled. Keep Sharp is retrieval only: there is no screen that shows the text again and calls it review.
An idea you already got right still comes back. It is asked another way than you first met it, and on review you type the answer from memory.