Does practicing puzzles change your IQ?

Practicing puzzles makes you better at puzzles, and that shows up as a higher result the next time you take a similar test: about 5 points on average from the first try to the second. The research does not show that the gain reaches the ability the test was built to measure. Large reviews of cognitive training find little or no transfer to reasoning in general, so treat a higher second result as practice, not as a higher IQ.

How much does a second attempt add?

The largest study of the question is a 2018 meta-analysis of 122 studies and about 153,000 people tested more than once on the same kind of ability test.

Comparison	Average gain
First test to second	0.33 standard deviations, about 5 points
First test to third	0.50 standard deviations, about 7.5 points
Third test to fourth	0.02 standard deviations, close to nothing
Figure and matrix content, first to second	0.32 standard deviations

The gain is smaller when the second test uses different questions, and it fades as the time between tests grows. The studies also varied a lot: some people gained much more than average and some lost points.

A gain that stops after two or three tries and shrinks with new questions looks like familiarity with the format, not a change in reasoning. You learn the rule types, the timing, and what a trap option looks like.

Does training transfer to general intelligence?

This is where the research has been most heated. In 2008, a study reported that training on a demanding memory game, the dual n-back, raised fluid intelligence scores, with bigger gains for people who trained longer. The idea spread quickly.

Later studies with stronger designs found something else:

• A 2013 replication that compared n-back training with an active control group found improved working memory but no gain in fluid intelligence.
• A 2016 review of 87 publications found no convincing evidence that working memory training improves abilities it didn’t train, when compared with active controls. Gains were real on tasks similar to the training.
• A 2019 review across many kinds of cognitive training, from memory games to chess and music, concluded that far transfer, to abilities other than the one practiced, is close to zero once study quality is accounted for.

One meta-analysis of n-back studies did find a small effect on fluid reasoning, about a quarter of a standard deviation. Critics showed it depended on studies with weak control groups. The fair summary is that if there is a general effect of puzzle practice, it is small and hard to separate from expectation and test familiarity.

Is there anything that does change measured intelligence?

Education does. A 2018 meta-analysis of more than 600,000 people estimated that each additional year of schooling adds about 1 to 5 points, and the effect lasted and appeared across broad abilities. That is years of learning, not weeks of puzzles.

Is it cheating to practice before an IQ test?

For a test you take for your own curiosity, no. It does mean the result will run a few points high, because part of what the test captures, how quickly you find a new rule, is less new to you. For a test used to make a decision about someone, practice on the same items would make the result misleading, which is one reason those tests are given under supervision with protected questions.

Why we sell practice anyway

We sell a practice plan and a workbook, so you should know what we claim for them. Practice makes you faster and more accurate at the four pattern types in our test, and it shows you which traps catch you. We don’t claim it changes your IQ, and the research above is why. If you retake our test after practicing, expect a higher result and read it as practice.

Our methodology lists practice among the test’s limitations for the same reason: “If you have practiced similar puzzles, your score may be higher than on a first attempt.”

If you want to practice for its own sake, start with the 30 practice puzzles and the method in how to solve matrix puzzles.

Sources

• Scharfen, J., Peters, J. M., & Holling, H. (2018). Retest effects in cognitive ability tests: a meta-analysis. Intelligence, 67, 44–66. doi:10.1016/j.intell.2018.01.003
• Jaeggi, S. M., Buschkuehl, M., Jonides, J., & Perrig, W. J. (2008). Improving fluid intelligence with training on working memory. PNAS, 105(19), 6829–6833. doi:10.1073/pnas.0801268105
• Redick, T. S., et al. (2013). No evidence of intelligence improvement after working memory training: a randomized, placebo-controlled study. Journal of Experimental Psychology: General, 142(2), 359–379. doi:10.1037/a0029082
• Melby-Lervåg, M., Redick, T. S., & Hulme, C. (2016). Working memory training does not improve performance on measures of intelligence or other measures of “far transfer”. Perspectives on Psychological Science, 11(4), 512–534. PMC4968033
• Au, J., et al. (2015). Improving fluid intelligence with training on working memory: a meta-analysis. Psychonomic Bulletin & Review, 22, 366–377. PubMed 25102926
• Sala, G., & Gobet, F. (2019). Cognitive training does not enhance general cognition. Trends in Cognitive Sciences, 23(1), 9–20. doi:10.1016/j.tics.2018.10.004
• Ritchie, S. J., & Tucker-Drob, E. M. (2018). How much does education improve intelligence? A meta-analysis. Psychological Science, 29(8), 1358–1369. PMC6088505