Wait for It: Delayed Feedback Can Enhance Learning

When answers to questions come at unpredictable intervals, memory improves

Join Our Community of Science Lovers!

It may seem that getting instant results would enhance learning, but various studies indicate a benefit to feedback that is delayed. Test takers are more likely to retain the correct answer if they receive it several seconds after providing their answers rather than immediately.

To understand why delayed answers improve learning, researchers at Iowa State University asked college students to give their best guess to trivia questions such as “Who coined the word ‘nerd’?” and “What color is a grasshopper's blood?” and to rate how curious they were about each answer. For half of the items, participants learned the correct answer immediately after responding to the question. For the remaining items, the answers either followed a four-second delay or an unpredictable interval of two, four or eight seconds. The students were then tested on the questions after engaging in unrelated distracting tasks.

The results, which were published in the November 2014 issue of Memory & Cognition, confirm the benefit of delayed feedback and show that it hinges on curiosity: in follow-up tests, participants answered more accurately when feedback arrived later but only for items that piqued their interest. The researchers suggest that delayed feedback encourages learners to anticipate the answer, which may increase their level of attention to it when they receive it. The effect was strongest when feedback was presented at unpredictable intervals, which is in line with previous studies showing that attention is enhanced when an upcoming event's timing is uncertain. So if you are studying with a buddy, ask that person to give you the answers after an unpredictable delay of a few seconds. If you are working alone, resist the urge to Google or look up an answer immediately and take a guess first.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


By the way, Dr. Seuss coined the word “nerd,” and a grasshopper's blood is white. If you were wondering about these answers, that delay may have just sealed them in your memory forever.

Tori Rodriguez is a journalist and psychotherapist based in Atlanta. Her writing has also appeared in the Atlantic, Women's Health and Real Simple.

More by Tori Rodriguez
SA Mind Vol 26 Issue 3This article was published with the title “Wait for It: Delayed Feedback Enhances Learning—But Only If You're Curious” in SA Mind Vol. 26 No. 3 (), p. 8
doi:10.1038/scientificamericanmind0515-8a

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe