One simple trick to improve your memory

Summary

Podcast Summary: "One Simple Trick to Improve Your Memory"

Title: Nudge
Host: Phil Agnew
Episode: One Simple Trick to Improve Your Memory
Release Date: April 7, 2025

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Introduction: Phil’s Personal Memory Challenge [00:00 – 01:22]

Phil Agnew begins the episode by sharing a personal story from 2023 when he was tasked with delivering a best man speech at his cousin's wedding on the Gold Coast, Australia. Determined to impress without relying on notes, Phil decided to memorize his entire 10-minute speech. However, despite spending hours reviewing the speech during a 20-hour flight, he struggled to retain the information. Frustrated and anxious about presenting in front of a large audience, Phil discovered a memory tactic that transformed his approach to memorization. This tactic, rooted in scientific research, became the focus of today's discussion with expert Charan Ranganath.

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Meet the Expert: Charan Ranganath [01:02 – 03:35]

Phil introduces Charan Ranganath, the author of the New York Times best-selling book Why We Remember. Charan is a professor at the Center for Neuroscience in the Department of Psychology at the University of California, Davis. He specializes in memory research and behavioral science.

Charan Ranganath: "The more work we put into trying to remember something, the better we will remember it later on." [01:02]

Charan explains that this principle is foundational to effective memorization techniques, challenging the conventional belief that passive review is sufficient for retaining information.

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Error-Driven Learning vs. Traditional Memorization [03:35 – 05:35]

Phil and Charan delve into the concept of error-driven learning, highlighting how allowing oneself to make mistakes can enhance memory retention more effectively than simply re-reading materials.

Charan Ranganath: "We often would think that it's best to actually try to memorize something properly. But study after study have shown that in fact, the best thing to do if you want to memorize something is give yourself the chance to fail rather than just trying to get it right the first time." [03:11]

Charan discusses a study conducted in July 2024 involving 74 Indian dental students. The students were divided into two groups:

• Group A: Utilized error-driven active learning, where they were tested and their mistakes corrected.
• Group B: Engaged in traditional lecture-based learning without active testing.

Results showed that Group A significantly outperformed Group B both immediately after learning and four weeks later, demonstrating the long-term benefits of error-driven learning.

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Phil’s Practical Application: Memorizing the Speech [02:00 – 03:56]

Phil recounts how he applied error-driven learning to memorize his speech. While walking on Kira Beach, he began practicing the speech aloud without his notes. Initially, he struggled, often needing to reference his first line multiple times. However, through persistent self-testing, Phil experienced a dramatic improvement within hours, ultimately delivering the speech flawlessly and from memory.

Phil Agnew: "The tactic I stumbled upon actually has some fairly compelling scientific backing." [03:56]

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The Generation Effect and Marketing Insights [06:15 – 08:02]

Phil connects the discussion to the generation effect, a principle used in marketing to enhance brand recall by requiring consumers to mentally generate information.

He references a 2020 study by Leo Burnett where participants were shown brand names with missing letters (e.g., H_B_C) versus the full brand names (e.g., HSBC). Those who engaged in mentally completing the names were 14% more likely to remember the brands later.

Phil Agnew: "Those who saw the brand with the missing letters were 14% more likely to remember the brand later on." [06:15]

This illustrates how active engagement, even in simple tasks, can significantly improve memory retention.

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Interactive Segment: Memory Quiz [08:02 – 09:35]

To demonstrate error-driven learning, Phil conducts a memory quiz with his listeners:

1. Question: Which US state has the most islands?
   • Answer: Alaska
2. Statement: New Mexico is the driest US state.

Charan explains that actively engaging with the first question by guessing enhances memory retention, whereas passively receiving the second fact leads to lower recall.

Charan Ranganath: "The fact that testing actually produces a memory benefit before you've tried, before you've gotten the right answer shows how powerful error driven learning is." [08:46]

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Foundational Study: Roediger and Karpik’s Research [12:03 – 14:14]

Charan delves into the seminal work of cognitive psychologists Henry Roediger and Jeff Karpik, who explored the testing effect in memory retention. Their experiments revealed that:

• Immediate Testing: Group tested immediately after learning performed slightly better than those who only studied.
• Delayed Testing: After one week, those who engaged in testing retained 85% of the information, compared to 50% retention in the study-only group.

Phil Agnew: "When Roediger and Carpic waited one week, the differences were huge. Students who studied the 14 times retained only half of what they had initially studied, but those who tested themselves retained three times more than the other group." [13:07]

Despite participants believing that repeated studying was more effective, the research clearly favored active testing for long-term retention.

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Spaced Learning: Overcoming the Forgetting Curve [15:29 – 17:58]

Phil and Charan discuss spaced learning, a technique first documented by Hermann Ebbinghaus, which involves spreading out learning sessions over time to combat the natural decline in memory retention known as the forgetting curve.

Charan Ranganath: "If you space out your attempts to memorize something, you'll do much better at retaining it than if you try to memorize it all at once." [14:33]

They explain that spaced learning not only enhances memory retention but also makes information more accessible from different contexts, unlike cramming, which ties memory to a specific time and place.

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Educational Implications and Spillover Effects [17:58 – 20:50]

The conversation shifts to the implications of these memory techniques on the education system. Charan criticizes the current focus on rote memorization of isolated facts, advocating instead for teaching students effective memorization strategies and fostering interconnected understanding.

Charan Ranganath: "We need to emphasize the actual learning process in education... if you're struggling, you feel like you're failing, but in fact, you're learning the most when you're struggling." [19:10]

He emphasizes that techniques like error-driven and spaced learning not only improve retention of specific information but also facilitate the recall of related concepts, known as spillover.

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Conclusion and Final Quiz Reflection [20:50 – End]

Phil revisits the memory quiz, highlighting that listeners are more likely to remember "Alaska" (which required active engagement) than "New Mexico" (a passively received fact), thereby reinforcing the effectiveness of error-driven learning.

Phil Agnew: "Error Driven learning really feels like one of these strategies that everyone should be taught from a young age." [20:50]

He concludes by encouraging listeners to adopt these evidence-based memory techniques in various aspects of their lives, from academics to professional presentations.

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Key Takeaways

1. Error-Driven Learning: Actively testing oneself and embracing mistakes can significantly enhance memory retention.
2. Generation Effect: Engaging in mentally generating information improves recall, a principle effectively utilized in marketing.
3. Spaced Learning: Distributing learning sessions over time combats the forgetting curve and leads to better long-term retention.
4. Educational Reform: There's a need to shift from rote memorization to teaching effective memory strategies to improve educational outcomes.

Notable Quotes

• Charan Ranganath: "The more work we put into trying to remember something, the better we will remember it later on." [01:02]
• Charan Ranganath: "We often would think that it's best to actually try to memorize something properly... but the best thing to do if you want to memorize something is give yourself the chance to fail rather than just trying to get it right the first time." [03:11]
• Charan Ranganath: "If you space out your attempts to memorize something, you'll do much better at retaining it than if you try to memorize it all at once." [14:33]
• Phil Agnew: "Error Driven learning really feels like one of these strategies that everyone should be taught from a young age." [20:50]

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Final Thoughts

Phil Agnew’s episode on "One Simple Trick to Improve Your Memory" effectively blends personal anecdotes with scientific research to present actionable strategies for enhancing memory. By featuring expert insights from Charan Ranganath, the podcast underscores the importance of active engagement and structured learning techniques in achieving better memory retention. Listeners are encouraged to apply error-driven and spaced learning methods to various facets of their lives for improved cognitive performance.

Transcript

[Phil Agnew]

Back in 2023, I was asked to give the best man speech at my cousin's wedding. The wedding was taking place in sunny Gold Coast Australia. And being the showman I am, I wanted to make a good impression. I wanted to write a great speech, of course, but I also didn't want to be checking my notes every few seconds. So I decided to memorise the entire 10 minute speech. @ the beginning, this didn't seem very daunting. How hard can it be to learn a short speech? But after hours and hours of staring at the speech on the flight, I realised that my memory was not as good as I had hoped. In the days before the wedding, I was getting nowhere. I had reread the speech hundreds of times, but it wasn't sticking in my mind. I couldn't recall it and I definitely wouldn't be able to remember it in front of a packed room of people. But then I stumbled upon a memory tactic that changed everything. A tactic that helped me learn the speech in just a few hours. A tactic that today's guest on Nudge has researched extensively. The tactic is built on on a rather simple idea.

[Charan Ranganath]

The more work we put into trying to remember something, the better we will remember it later on.

[Phil Agnew]

That's Charan Ranganath, the author of the New York Times best selling book why We Remember.

[Charan Ranganath]

I'm Charan Ranganath. I'm a professor at the center for Neuroscience in the Department of Psychology at the University of California, Davis.

[Phil Agnew]

Today we'll cover Charan's pioneering research on memory and he'll share the tactic that anyone can use to remember more. All of that coming up. Angel City Football Club didn't become the world's most valuable women's sports franchise by accident. They did it with a little help from HubSpot. When they started, data was housed across multiple systems. But HubSpot unified their website, their email marketing and their fan experience in one platform. This allowed their small team of three to build an entire website in just three days. The results were nearly as good as the results results happening on the pitch. They saw 350 new signups a week and a 300% database growth in just two years. If you want to grow like Angel City Football club, then visit HubSpot.com to hear how HubSpot can help you grow better. I was desperate to remember my best band speech. I'd spent the 20 hour flight to Australia reading it over and over again. But it didn't work. Then while walking up and down Kira beach watching the sun rise, I Tried something different. I decided to test myself out loud. I'd start delivering the speech without my notes, just to see how much I could remember. At first I was awful. I had to check the first line at least three times. But my progression was dramatic. Within a few hours, I'd memorised the whole thing and two days later I delivered it notes free, completely by heart, to a room full of Aussies. Time in my life, girls would talk to me and they would say, where's your fit kiwi cousin? The tactic I stumbled upon actually has some fairly compelling scientific backing.

[Charan Ranganath]

We often would think that it's best to actually try to memorize something properly. But study after study have shown that in fact, the best thing to do if you want to memorize something is give yourself the chance to fail rather than just trying to get it right the first time. The more work we put into trying to remember something, the better we will remember it later on.

[Phil Agnew]

In his book, Churan writes that this principle builds on how our brain functions. He says we are wired to learn from our mistakes and challenges, a phenomenon known as error driven learning. This simple principle explains why re reading my best man speech over and over didn't help me remember, but testing myself on the best man speech did.

[Charan Ranganath]

So there's a number of studies, for instance, showing that if I were to test you on your memory for something that you had tried to memorize, like again, you're trying to learn a foreign language. Well, if I test you on it and then I give you the answer after you guess it, you will do much better at retaining that information than if you just tried to memorize it and just say it to yourself over and over.

[Phil Agnew]

In July 2024, a group of researchers tested this idea with 74 Indian dental students. The students were split into two groups. Group A had 37 students and they were tasked with learning using the error based active learning memory system. This is where they would be tested and their mistakes would be corrected when they were tested. It was just like me testing myself on the beach. Group B, also with 37 students, learned using regular lectures. So a lecture was delivered and they had to remember what they could. This was like me re reading my speech on the plane. The topic they were learning about was itraumatic restorative treatment, a dental procedure right after the lesson. The students who learned through testing got an average score of 21 out of 25 on the test. The students who learned through the regular lectures performed worse. Their average score was 17 out of 25. And then four weeks later, they Repeated the test. The error driven learning group, the ones who were tested, they still remembered a lot more. They scored 18 out of 25. The lecture group forgot pharma more and they scored 14 out of 25 on the test. The error driven learning group remembered 23% more immediately and 30% more four weeks on.

[Charan Ranganath]

Even though this is counterintuitive for some people, and in fact, studies on the testing effect have shown that often people are very surprised and they think trying to memorize something perfectly is much better than giving themselves the opportunity to fail. But I think everyone can appreciate that if you're trying to be in a play and you're trying to memorize lines, you don't want to just look at the script over and over. You want to try to say it from memory and then look at the script. Right? Likewise, anybody who's driven around a place will get a better memory for it than if they're sitting as a passenger. Right? And the reason is, is that you're generating guesses about where things are going to be.

[Phil Agnew]

This links back to an effect I've spoken about before on the show known as the generation effect. It's one that's been used in marketing and advertising, and it suggests that if consumers have to mentally work to generate an answer, they'll have better brand recall. So this is a 2020 study by Leo Burnett. In it, participants were shown brand names with missing letters, for example, H, B, C. Others were shown the full brand name, so hsbc. Both sets of groups were asked to remember the brand counterintuitively. Those who saw the brand with the missing letters were 14% more likely to remember the brand later on. They had a recall rate of 92% rather than 81%. Making them work made them remember more.

[Charan Ranganath]

And this is actually a big principle in machine learning as well, that you don't want to teach an AI, for instance, everything that it's experiencing, so to speak. You don't want to teach it every bit of every piece of information. You want to give it a chance to guess and make a mistake and then tweak the connections in the AI system so that it will better be able to produce the right answer. And human memory works the same way. And in fact, it's so powerful that you can even get an enhancement in memory if you test yourself before you know the answer. So if I were to give you a word in Swahili and ask you to guess what the meaning of that word is, you're probably going to guess it wrong if you don't Know Swahili. But just the act of guessing it will make it easier to retain the information about the right meaning when I give it to you.

[Phil Agnew]

I think it's time we run a little test to prove this. So let's do a little quiz. I'll ask you a question and you have to guess the answer. Which US State has the most islands? Alright, make a guess. Genuinely think of a guess in your head. Okay. Have you made your guess? Well, the answer is Alaska. Alaska has the most islands. Now to test if error driven learning works, I'll do the opposite. I'll share a fact with you without testing you. So the fact is New Mexico is the driest US state. Only 0.2% of its total is covered by water. Now, at the end of the show, I'll refer back to these two facts and we'll see which ones you remember.

[Charan Ranganath]

The fact that testing actually produces a memory benefit before you've tried, before you've gotten the right answer shows how powerful error driven learning is. And we've shown in our computer models how this can happen. It happens through being able to give the brain a chance to generate the wrong answer. And then when you get the right answer, you can wipe out the wrong answer. And as I mentioned in the book, often the reason why we don't remember is because our memories are competing with each other. And so if I were just to give you the Swahili word, there's many different ideas that can pop up. But if I give myself the chance to fail at remembering it and then I get the right answer, my brain can wipe out some of the bad answers and emphasize the good answer.

[Phil Agnew]

Error driven learning works best when you can figure out what went wrong and improve. But there is a caveat. If you're totally lost, mistakes won't help. Turan gives an example of this. In his book, he talks about surfing. With surfing, there is so much happening at once when you are trying to learn that it is very hard to tell what you did right or wrong. Did you step in the right place? Did you jump on the board at the right time? Did you paddle hard enough? To learn what you're doing right or wrong, you need to be told, usually by an instructor, what you are doing right and what specifically you were doing wrong. You will struggle to learn even if you're testing yourself. If you're just flailing around aimlessly, you need to know what you're doing wrong in order to improve. Now, coming up, we will cover why cramming doesn't work, what the education system gets wrong and we'll see what you remembered from that quiz. The podcast I'd like to recommend today is Creators Are Brands, hosted by Tom Boyd and of course brought to you by the HubSpot Podcast Network, the audio destination for business professionals. Creators Are Brands explores how storytellers are building brands online, from the mindsets they use to the tactics they apply, including some of the business troubles they get into. This podcast breaks down what's working so you can apply the tactics to your work. It's a fantastic show, so listen to Creators, Our brands, wherever you get your podcasts. If you're anything like me, that period before you have to come up with an idea for a campaign is terrifying. You don't know what to do. You don't want to just rely on gut instinct. It's hard to think of a good idea, but there is a very interesting solution. It's GWI Spark, your free AI powered research assistant. GWI Spark gives you fresh insights on your target audience in seconds so you can get inspired, validate hunches, and build smarter campaigns backed by rock solid consumer data. Don't go into your next campaign blind. Use Spark for your next big idea. Sign up for free at GWI. That's GWI.com podcast. Hello and welcome back. You are listening to Nudge with me Phil Agnew. To better understand the impact of error driven learning, we need to take a look at the seminal study behind it. Cognitive psychologists Henry Roediger and Jeff Karpik were the first to question if testing can boost memory, and they set up a clever experiment to study it.

[Charan Ranganath]

So basically what they did was they would ask people to try to memorize words. And they've done many different studies. One of them is they ask people to memorize these words in Swahili. And so some of them are just told, we want you to study them. So they would look at the meaning and then they would try to memorize them.

[Phil Agnew]

Roedinger and Karpik had two groups of students memorize foreign words. One group memorized these words by rereading them 14 times, and another group read the words three or four times and then completed three tests in which they had to recall as much of what they studied as possible.

[Charan Ranganath]

What they found was the people who just studied and tried to memorize them did better or a little bit better than people who tested themselves on the material but didn't really study it. If you tested them immediately, then the study condition would do better.

[Phil Agnew]

That's not really a surprise because the study group had four times as many opportunities to read those passages as the ones who were tested.

[Charan Ranganath]

But when you waited like a few days, what they found was that the people who tested themselves would retain about 85% of what they had memorized, whereas the people who just studied that information were only retaining about half of what they memorized. So in other words, over time, the people who tested themselves were much, much better than the people who repeatedly studied the information.

[Phil Agnew]

When Roediger and Carpic waited one week, the differences were huge. Students who studied the 14 times retained only half of what they had initially studied, but those who tested themselves retained three times more than the other group. They retained 85% of the knowledge. Although the students believed they learned more by studying, they actually gained far more by testing themselves.

[Charan Ranganath]

But when they asked people while they were doing the experiment, people overwhelmingly said that they thought studying would be easier than testing themselves. And we'll be more effective, right? So it shows how counterintuitive this effect really is.

[Phil Agnew]

This goes against our conventional belief. We believe that studying information over and over leads to recall, but it doesn't. Studying briefly and then testing boosts recall far more. And this has big implications for anyone who needs to remember more, from actors memorizing their lines to students studying for a test.

[Charan Ranganath]

I think most people probably have crammed for a test at some time or another during their education. And what you find is you do all this memorization for these tests, and by summer vacation, kids have forgotten everything that they tried to memorize before. So what's going on there? Well, one of the things that people have shown over and over again is that if you space out your attempts to memorize something, you'll do much better at retaining it than if you try to memorize it all at once. So, for instance, if you just decide, okay, I'm a really busy person, I've got 10 hours to do this, you know, foreign language learning that I'm going to do, then you're better off splitting that into a bunch of one hour sessions than trying to do 10 hours all at once. I mean, nobody's going to do 10 hours, but maybe not the best example, but you know what I mean?

[Phil Agnew]

This is spaced learning. It was first documented by Herman Ebbinghau. He discovered the forgetting curve, which shows that we rapidly forget new information. Memory declines steeply right after learning, but it levels off over time. To combat this, Ebbinghaus proposed space learning, where revisiting information at increasing intervals helps us retain it for longer. Ciran and I, we spoke about this in much more detail. On his first appearance on Nudge. This technique strengthens memory by reinforcing learning before the forgetting occurs, making it much more effective than cramming during an all nighter.

[Charan Ranganath]

So people do an all nighter for an exam and what happens is that their memory for that experience is tied to one place, one time, and so the next day they might do pretty well on the test because the context hasn't changed all that much. In other words, if I have something that is from yesterday, my mental state at the time of doing the test is not nearly as different as it was one week ago. But the beauty of spacing out your learning is every time you relearn, you're putting in new effort into learning because the context has changed and you're not going to be very good at remembering it. So if I space out my attempts to learn it, let's say, by once every three days, well, every time I do this studying, I will get more bang for my buck because my brain is going to try to produce the right answer, but it'll produce the wrong answer. And so we even have a computer model that came out last year that shows how this can happen in the brain. And what happens is that the more you space out your learning, the less the memory is tied to a particular place in time. The memory becomes updated over and over again so that it's something you can generally access from anywhere at any point in time. And what's beautiful about that effect is after the exam is over, let's say if you've taken a midterm exam and then a few weeks later you have the final examination exam, if you spaced out your learning now, that information is much more available to you and easy to pull up than if you crammed for the midterm. What happens is, oh well, now the finals coming, I have to cram all over again, right? So it turns out to be quite an inefficient strategy, even in the fairly short term. And the only time it really works effectively is if you cram literally right before an examination. But again, if you really want to learn, you're better off spacing.

[Phil Agnew]

Spaced learning and error driven learning don't just help you remember more about what you've studied, these techniques actually help you remember more. In general, this is known as spillover. So spillover means when you're studying one particular topic, you won't just learn about that topic, you'll actually pick up and remember the things related to that topic. So one study tested participants on facts about topics like toucans, the Big bang and foreign words, lots of different subjects. When people recalled one fact from an article about something specific, their recall of the related facts in that same article actually improved. So this suggests that testing could have a positive spillover effect where these memories are interconnected. And all of this can make our current education system seem quite silly, because right now students are encouraged to memorise these disconnected facts, like the dates of European battles or different formulas in mathematics. But if these facts aren't linked together, we won't benefit from spillover. If students were encouraged to understand how the facts interconnected, so learning about specific battles, but then also about the broader political movements that linked them, well, if that was the case, then the students would benefit from spillover and they would remember more.

[Charan Ranganath]

I think this speaks to a bigger issue that I really get evangelical about in the book, which is I think we need to emphasize the actual learning process in education. It's pretty shocking that we expect students to memorize all these things in their classes, and almost no student gets an explicit training in how to memorize and training in the most effective strategies for studying that allow you to retain this information. It's not surprising that students struggle. And then on top of it. I don't think that kids are taught that you're supposed to struggle to learn. Learn. I think they're again, under the illusion, because everybody seems to have this illusion that's supposed to be effortless. And so if they're struggling, they feel like they're failing, but in fact, you're learning the most when you're struggling, as long as you get the right answer and you're eventually taught the right answer. And so in my classes, you know, I'm not perfect by any means. And, you know, if I had more time, I could probably. And more resources, we could do more. But I quiz people pretty regularly on the material. And the reason I do this is not because I want to torture my students. And in fact, or it's not even because I want to see how much they know. In fact, I allow them to drop the worst two quizzes from their grade so that they don't have to worry about it, but the reason I do it is by frequently testing them, I'm giving them a chance to learn and memorize the material, and then when I test them again later, they do much better as a result.

[Phil Agnew]

Testing is simply a more effective way to memorise things and I think we can prove it. Let us go back to our quiz. Now, which US State has the most islands? Can you remember? Well, most of you should. After all, I tested you on this, so most of you should remember it's Alaska. Now which US State is the driest? Do you remember? Chances are a higher percentage of you will have forgotten that the answer is New Mexico. You were told this is a fact and you didn't have to generate an answer for yourself. I don't know if that worked, but if it did, well, it's a nice way to end this episode because error Driven learning. It really feels like one of these strategies that everyone should be taught from a young age. It helps students prepare for tests, makes learning a foreign language far easier, and even helped me deliver an acceptable best man speech without my notes. That is all for today's episode of Nudge. Thank you so much for listening. I hope you remember as much of this podcast as possible. Massive. Massive. Thank you to Turan for coming on. His New York Times best selling book why We Buy is genuinely fantastic. There is lots of fascinating insights into how our memory works, including a very interesting study on Inception style sleep learning. I think the book's worth reading just for that alone. I've left a link to the book in the show notes if you want to check it out. And if you want more from Nudge, please do check out the show on YouTube. I've started to create new videos which are quite dramatically different from these podcast episodes that you're listening to. They cover the same topics, but they go into much more detail about a specific story or an event and I add some really handy animations and visuals on there as well. There are two episodes that should be published by now that I think you'll like. One is on the Simon Sinek Problem. This covers survivorship bias and the narrative fallacy and the other is called the Controversial Diet that Conquered the World. It looks at black and white thinking and why the Atkins Diet became so popular. If either of those sound interesting to you, then go and search for nudge podcast on YouTube. You'll be able to watch it there or just click the link in the show notes. That is all from me, your host Phil Agnew this week and I'll be back on Monday for another episode. Cheers.