 All right. Hello, everybody. Actually, I'm Todd Becker, for those of you who don't know me. And I'm going to talk about desirable difficulties. And the theme is using hormesis to learn more effectively and basically training your brain to remember things better. I'm really happy to be here at the 10th AHS. Actually, the first one here was the only one I missed. I've been to all the others. And I was very, very sad that I missed that one. So I made a point to come to Harvard and from that point on. So I've given five previous talks at AHSs and a range of topics from how to overcome myopia and prove your vision, altitude, the benefits of living at high altitude, and how to overcome obesity and addiction, all using hormesis, which is the judicious use of small doses of stress in the right way to stimulate and improve your health. So today, we're going to apply that to learning. So just an overview and outline of my talk. I'll start with the fact that we're all using digital technologies, the internet, smartphones. And we believe that that makes learning easier. It's easier on the professor. It's easier on the student. But it's not necessarily more effective. In fact, studies show that making learning harder in certain ways actually can make it more effective and can improve your memory. And this is where this concept of desirable difficulties comes in, and I'll get into that. And this is also where we can go back to our ancestors. And that's the connection with AHS principles and look at pre-modern oral cultures and how they develop memory, because this was before the invention of writing. They had to remember things without writing. And we'll get into that. And how are you going to apply some of those learnings to improving your own memory and retaining information better? So let's think about digital technologies. Computers, the internet, these are actually very wonderful things. If you want to search to find out if you can't remember, who are the members of the Rolling Stones? You can look that up. I forgot that one. OK, Charlie Watts, yes. Or if you want to fix your engine, you used to have to learn it from tradesmen or look it up. You can now find a YouTube on that. So it's definitely a plus. But people assume that just making it easier makes learning more effective. But maybe that assumption is wrong. Maybe some of the ease of technology, digital technology, actually makes it harder to remember things. So two professors here in the UCLA Psychology Department, they're colleagues of Aaron's, Robert and Elizabeth Bjork. About 30 years ago, they asked, what are the factors that increase the effectiveness of learning? Primarily in the classroom, but just in general. And they looked at some of the dogmas around how to prepare lesson plans, cover one topic at a time, study consistently in the same conditions. And they found that as this graph summarizes, yes, these efficient methods give you great short-term retention. You can pass that test that you just crammed for. But that fades over time. And they found that actually adding some more effort, some more engagement into the process of learning leads to better long-term retention. So let's contrast this. So on the left side here, you see some of the practices that do promote short-term learning. So learning consistently, study in the same place, same time of day, in the same routine. Massing, what is massing? Well, in terms of teaching, it's teaching one topic at a time. Teach it, take a test, move on to the next talk. What is it from the student's point of view? It's wait till the night before, study, cramming, just master that past the test. Students typically study by just re-reading their notes. I've got it. But what the Bjorks found is actually these have short-term effects. And that the way you really want to get at long-term learning is to vary the conditions. Study at different kinds of problems, different times of day. Space out the study sessions over time. Study, put it away, come back to it. Actually, some forgetting in between those sessions is important. There's a study that just came out from Max Planck Institute with rats, showing that if the rats were trained to run a maze, it's very short intervals. They could remember it, and then they couldn't run the maze the next week. If they spaced out the learning, what's very interesting is when they were being trained in close intervals, different sets of neurons were being activated, not the same original ones. So they weren't reinforcing those same pathways. When they spaced out the sessions, the rats would forget. And then when they re-remembered, they activated the original neurons. So there's an important forgetting process that's involved here. Instead of just rereading your notes, the Bjorks found you actually have to test yourself. And this gets to the idea that encoding the process of laying down the memory should be the same as retrieval. So you should rehearse exactly what you're going to have to perform, rather than just reading it passively. OK, so this is where this concept of desirable difficulties came from, and that's a term they coined back in 1991. And are they just saying you should make learning difficult and put obstacles in the way? Absolutely not. It's only difficulties that force active engagement with the material that really provide this benefit. And so by having effortful, sometimes even frustrating, processes of learning the material, that level of challenge really reinforces learning. It's very key, though, that you don't just fail, eventually you have to succeed. And it's that last success that consolidates the learning. So I think this concept of desirable difficulties fits into the more general concept of hormesis, which is what I write my blog about. My blog is Getting Stronger for those of you who are interested in. And the idea of hormesis is a beneficial type of stress exists when it's at a low dose, not too high, not too low, just at the sweet spot. And essentially, you can think of it as a stimulus. A good example is weightlifting. If you just lift light weights, you'll never build muscle mass. You have to increase the level of stress or stimulus to get that performance gain. But you can't try to lift weights that are too heavy. You can actually damage your muscles. And this concept sort of shown in the diagram there that at a low dose you don't get an effect. There's a sweet spot where you actually get a stimulatory effect, and at too high a level, it's detrimental. So why do desirable difficulties work in learning? Well, I think a couple key points that the Bjorks pointed out. One is to get this encoding, the learning process has to be the same as the retrieval process. Again, you have to rehearse what you're going to perform. Also, instead of you going for consistent conditions, you want to learn the material coming from a variety of different directions. Maybe you read it, listen to it, look at visual, auditory inputs, different times of day. The more different styles or modes of teaching, the more robust the information. And finally, you need to push yourself. And this is, again, this hermetic idea that you want to go to the edge of your abilities, but not so difficult that you can't perform. You need to succeed. OK, so let's take some practical examples of this in learning in the classroom. Note-taking, right? We all have laptops. Students generally take their notes on laptops. It's faster. You can keep up with the lecture. You can take almost stenographic notes, like a court reporter, verbatim. And you can search the notes later. However, does that really lead to learning? In fact, sometimes people mindlessly take those notes and they don't process the information. So handwritten notes, yes, they're slower. They're more legible. But you have to paraphrase sometimes. And there's actually an interesting study that was done in 2014 by Merler and Oppenheimer, where they looked at undergraduates and had them listen to TED talks. And half of them took notes on their laptops. The other half hadn't written notes. And then they were distracted with other activities. And they had to come back and take a test later. Ones who took notes on their laptops, they could capture a few more dates and names and details. But it's the ones who took the handwritten notes that process that information and perform better on conceptual questions, like comparing cultural differences or things like that. So there's some advantages to actually using your hand. And you can go one step further. And I think the point here is take notes in your own words better yet. Make diagrams, charts, tables. One of my favorite ways to do this is mind maps. A lot of people are familiar with this, but you can actually take notes using mind maps. And as you hear one topic, you draw a branch. And then you can add more detail. You can add color and doodles and make that more vivid. And sometimes that makes it stick a lot better. Here's something that was surprising to me. I always assumed that if you read books that were printed in Ariel or Times New Roman, easy to read fonts, you would understand and recall that better because you could skim. But actually turns out that there was a study using disfluent fonts, which are hard to read, which slow you down. And the study showed that students retained that information better. So can you read this font here? Yeah, sans-forgetica, right? And the thought is your mind is having to complete the picture and it's actively working. Now maybe you wouldn't wanna read a novel at the beach written in sans-forgetica, but I think it proves a certain point. So then let's go back and now look at this question of technology and even the invention of writing. And does that really help us remember? Well, there's a famous dialogue, Plato's dialogue, Phaedrus, and basically Plato just wrote down what Socrates said, right? And Socrates was actually the philosopher here, but there was Theuth, who was the supposed mythical inventor of writing and famous who was the king of the gods. And here's the dialogue, I'll just read it because I think it really sums it up nicely. Theos says, my invention of letters will make the Egyptians wiser and improve their memories. And Thayma says, hmm, no. This invention will produce forgetfulness in the minds of those who learn to use it because they will not practice their memory. Their trust in writing produced by external characters which are no part of themselves will discourage the use of their own memory within them. You have invented an elixir, not of memory, but of reminding. And you offer your pupil to the appearance of wisdom, not true wisdom. So I think this was kind of an early view of our over dependence on technology, perhaps. And so what I wanna do now is go through memory skills. What can we learn from old, older, pre-modern cultures, oral cultures, the Greeks and the Romans before writing was widespread? How can we apply those skills to learn information better ourselves? Some insights into improving your memory, the tip of the tongue phenomenon I'll talk about, memory competitions, some practical applications, and then I'll get into why it's important to improve your memory because it's not about rote memorization. I mean, that's not what it's about. It's about creating a framework onto which you can layer knowledge. So one of the best books on this topic, I highly, highly recommend this book, is by Lynn Kelly, it's called Memory Craft. And she was an anthropologist, a science writer, and she researched how some of these oral cultures practiced memory and developed memory. She herself describes herself as having a poor memory. She did not do well in subjects like languages that required memorization. But after studying these techniques, she says, you know, I can do this. She entered Australia's memory competition in the senior category and won it two years in a row. And after that, she decides to learn French and Chinese in her 60s. So I'm like, okay, this sounds like somebody I'm interested in. So what did Kelly find? Well, she studied a bunch of these ancestral cultures, pre-literate cultures, and she found that they used song, dance, storytelling, artwork, work, and even sculpture to consolidate memory and pass them on. So let's look at the Aboriginal Australians. They had this technique called song lines, which would combine dance and movement and song. And they memorized over 800 kilometers of paths through the continent of Australia, and they passed that down through generations. They documented their ancestry and their geology for over 10,000 years back to the previous Ice Age, and that's been validated by geological evidence that they actually had the story right. The Navajo also used stories to account for their genealogy, their geology. They memorized copious amounts of encyclopedic information around plants, even over 700 species of insects. They could recount through their stories. And then Kelly studied the Neolithic Britons, and she came up with an explanation for Stonehenge. And turns out she believes that it's essentially a memory device to pass down their culture. And here you can see one of the Papua Tula artists pointing out a particular well, water well, along this long route that he goes through and dancing out the route. So we go now to the Greeks and the Romans, and there's this famous memory technique called the method of loci or loci in proper Latin. In Cicero, the Roman orator used this and he documented it in a book called Add Herinium. And here's how it works. An orator thinks of a building or a city that he knows very well, and he places objects and events in the rooms of that building or along the route and often adds vivid imagery to it, sometimes humorous or colorful or absurd. And that strengthens the memory. And this can be used to memorize any sequence, you know, a story, a speech. And so we're gonna go through an example of this and show you how this works. So think of your own home, but here's just a generic two-bedroom apartment. And the experts say you should divide it into groups of five or 10. So it's easy to keep track in case you missed a spot. So here, one is in the living room, two is by the fireplace, three is in the kitchen, four is the dining room, and then we have the rest distributed through the bedrooms and the master bedroom. So now let's say you wanna memorize the first 10 presidents of the United States. How do you do this? Okay, you place them around the spot. So Washington is in the living room, Adams is by the fireplace, Jefferson is in the kitchen, Madison in the dining room, Monroe is moving down the hallway, and we've got John Quincy Adams and Andrew Jackson in the bedrooms, Martin Van Buren in the bathroom, William Henry Harrison in the master bedroom and John Tyler is in the other bathroom. Now, maybe you don't remember these names, so come up with some funny mnemonics. So Washington washes your feet as you come in and Adams is looking at the Adams in the fireplace. Soundford Jefferson Jay, Jeffy Pop, he's making popcorn, which he serves to Madison, who's Madison because he hates popcorn and Monroe is rowing, he's a man rowing down the hallway, John Quincy Adams is in his, got a quilt on his bed made of Adams, Andrew Jackson is playing jacks on his bed and I like this one, Martin Van Buren, there's a vanity and a bureau in the bathroom, so I can remember that one. William Henry Harrison, oh, there's a hearse on the bed and he in fact died 32 days in the office from pneumonia, so okay, got that one and John Tyler is tiling the floor. Okay, so let me see how many of you can remember this at the end of the talk. How many of you have had this experience? You're at a party and you were introduced to somebody and then on the way home, what was their name? It's on the tip of my tongue. Sometimes you can remember the first letter of the name or the number of syllables or something about the meaning and normally these things come together and produce a memory, but it's kind of failing. So memory experts advise, don't get a hint, don't ask your friend, don't Google it, don't look it up, give it some time, wait a few minutes, maybe a few days, maybe a few hours, unless it's really critical, it often will come and when I started doing this and your recall improves, you're just allowing that process to happen. Don't be too quick to look it up. The apex of memory are these memory athletes who compete, right? The amazing feats of memory that you think are not possible, so I'll give you one example, this guy, that ink, see is that he memorized a shuffled, randomly shuffled deck of cart and could reproduce it in 12.74 seconds. Look at it for 12.74 seconds, it's taken away, he's given another deck, he has to reproduce the order. Incredible. Memorizing pi to 70,000 digits, just sitting there off the top of your head or looking at 218 faces, names and remembering them 15 minutes later, okay? So all of these use the same method of association that Cicero and the method of loci, they're associations and you come up with tricks for remembering cards or numbers. So the mind is really incredible here. How do actors remember their lines? I mean, here we are basically in Hollywood and you've got all these people around you who can remember long siliquies or dialogues, many, many words. Well, it turns out they use similar techniques to the Australian aboriginal song lines. They often use pitch and intonation and cadence and emphasis where it's almost like choreography, they combine it with the steps they're taking and that reinforces the memory. And you make a lot of associations. Practicing out loud, going back to what the Bjork said, the process of encoding is reinforced by actually rehearsing what you want to deliver. Mental math, right? Again, here's where technology helps. We're all grateful for calculators and spreadsheets but our math muscles wither and I found that I work with a lot of new scientists and engineers right out of college and they're always going right to their calculator and sometimes they come up with absurd numbers that don't make any sense because they've lost that mental intuition. So practice estimating things. Can you do tips in your head? Can you guess how many cars there are in the United States? Just make some assumptions. The more you do this, the better you'll get at it. Navigation, of course, the ancients use stars and tracks, animal tracks or observations along the way to find their way. We now have GPS. It's great. It's a boon. We all use it to get someplace on time and even estimate when we're gonna get there. But sometimes it can get you lost. There's stories of planes and ships going off course for hours. Hikers die in the wilderness every year because the batteries died. They didn't really know where they are. So here's something I applied to myself during pandemic to be less sedentary. I started taking hour long, sometimes two hour long walks at lunch break. And I realized I didn't even know the town I lived in. And I would drive kids to a sports event or to a friend's house. And I sort of knew the way there. I started memorizing all the streets as I walked. And I now know most of the streets in my town. I can tell you how to get anywhere just because I found that was kind of a fun game. And now actually I know my, I have a sense, not just of how to get there, but a sense of where I am. And so you can apply this to where you live, to where you commute to. So why do these skills work? There's a part of the brain called the hippocampus. And this is where short term memories are formed. It turns out there's three interesting kinds of cells there. There are these enterinol or grid cells. And these are almost like your natural GPS. There's a cell for specific locations, right? There are face cells. So Aaron's face actually is a neuron somewhere in my hippocampus, right? And I can recognize him with a mask on or different types of day or if his hair is longer. It's that same face cell that gets activated. Pretty interesting. Time cells record sequences like melodies. And so if you think about it from an ancestral evolutionary point of view, these are the kinds of cells that helped us navigate our physical world and our geographic world. So some practical applications of memory skills. You can apply this. Learn the streets where you live. You'll get a better sense. How about your colleagues and your friends? Do you know the names of everyone you work with? You know, you might actually build a better sense of your network. How about books and movies? I found that I test myself constantly now when I'm watching a movie or reading a book. Can I remember all the characters, the plot sequence? Or do I just read it and then forget that book the next day? So it builds a greater sense of pleasure. And even one that I think is really cool is plants and birds. If you walk around, do you know the names of all the plants where you walk? Can you recognize bird songs? It just gives you a more or less awareness of your environment. One question that comes up about memory is what about Alzheimer's and dementia? Okay, well, Lynn Kelly has an interesting point here that is one of the most devastating aspects of dementia is loss of personal identity. You don't recognize who you are, who the person is. She found that the Lakota had this practice called winter counts where they would take skins and they would mark a symbol for every year of your life. Some events of that year, when you were 17, when you were 18, and you keep a record of that and then you tell stories about that. Well, you could do the same thing with photo albums. This is an intergenerational thing. You can sit down with your family, put together that for each year of your life. It might take a little bit of research. And then when somebody's older, they have a reference point. You can leave this with a caregiver, right? It's these stories that get passed down. Now we get into nonverbal skills. And here, I think this is where you go beyond just recognition and recall to actually recreating a skill. That's the hardest type. So I'll give examples just quickly from three different areas, music, design, and athletics. Can we apply these memory skills or desirable difficulties here? Well, in music, there's kind of this dogma that you should practice everything perfect. Don't make any mistakes, because if you make a mistake, you're gonna learn the mistake. Well, a more enlightened approach is actually add variations in tempo. Try adding some difficulty. There's this famous ragtime pianist, James P. Johnson, who wrote Carolina's Shout in 1921. And he would practice with the lights out or put a sheet over the keyboard to develop his sense of touch. So he's using desirable difficulties, hormesis, to get better. Design, we have computer aided design. It's very easy to make revisions, right? To coordinate with other drawings, and it's great. Everybody relies on it. But design is still taught primarily at first as a freehand skill. You need to get that design sense to do concept development, to spur creativity, and then you go to CAD, right? Athletic skills. Should we practice everything consistently and perfect? What if you wanna learn to throw more accurately? Well, the Bjorks have a really interesting example of kids who had to learn a beanbag toss. And they had to hit a target three feet away. And one group, group A, always practice at three feet. Three feet, three feet, three feet. Group B never practiced at three feet, but only at two feet or four feet. So they never actually practiced at the test condition. When they were tested 12 weeks later, you can see here for both the eight and 12 year olds, group B, that varied the distance, but never practiced the actual condition, came closer in inches. The Bjorks also say that, you know, you shouldn't always strive for perfection. You should actually strive for failure, and then correction, because it actually forces you to pay attention. So they did another study with word pairs. Word pairs that maybe didn't necessarily go together, like whale and mammal. One group was shown the cards, just whale, and they had to guess, what are their words? And they guessed wrong 97% of the time. The other group was shown the two words together, whale and mammal, all together. The group that guessed wrong and then corrected themselves, averaged 65% correct score on the test. The group that was just shown the two words, this is like reading your notes, rather than testing yourself, got it only half the time. A couple more things on skills training. There's a really neat book by Daniel Coyle on how mastery is taught in sports and in other activities. He looked at Brazilian soccer stars, like Pele, who came out of these soccer academies. They developed a game called futsal, with a ball that was half the size and twice the weight of a normal ball. And it was a lot harder to pass and learn skills, but it led to six times as many touches. And then when they played normal soccer, they did well. Flight simulators, another example. During the 1930s, one out of every four air delivery flights was ending in a crash. And so President Roosevelt said, we have to do better at training, rather than just training on the ground and in schools and just minimal flying. So Edwin Link built these flight simulators, which were very small, intense simulators so that you could pitch and yawn, roll, and they would practice dives and stalls, and you could all simulate it. And the fatality rate went down and they built 10,000 of these, and that was used in training in World War II. So to wrap it up, am I saying you should never use digital technology? No. Just be wise about when to use it and then what parts of memorization to reclaim for your brain. So one-time lists, shopping lists, calendar entries, you don't need to memorize all that, but how about your credit card number and your passwords? Can you really get that down? How about complex calculations? Well, yes, use your calculators for that, but you can often develop intuition by making estimates. And finally, there's some skills where we depend on augmentation like our automobiles for safe driving, but there's some very personal motor skills like athletics and music that are always good to keep close to heart. So to wrap it up, five things to kind of remember here where you can learn from our ancestors, some of these skills, and put them to practice in daily life. First of all, take notes in your own words. Engage with the material. Don't just take notes stenographically. Use diagrams. Test yourself constantly. This is the key principle of the Bjorks. Don't just read it and think you know it. Put it away, test it, and do it at different intervals and under different conditions and space it out. Number three is a key one. Resist hints. When you have that tip of the tongue phenomenon and you can't remember it, wait a minute, wait an hour, it'll start coming to you faster. Experiment with memory palaces. It's weird. I thought this was the most bizarre idea, but I actually used it to practice this talk. And it helps. I'm kind of walking through the house here. Make it fun and enjoyable. Pick an area that you really want to master. It could be streets, it could be people, it could be some facts of history, books and practices. You'll find it gives a real sense of pleasure. So if you're interested, there's some further reading and I'm sure this will be on the video. I especially recommend the work by the Bjorks and this book by Lynn Kelly on how our ancestors memorized. If you're interested in Hormesis, my blog, it's a wide variety of topics which I've talked about at other AHSs. So I'll pause. Any questions? It's systematic. It's like two and four feet practicing around sort of like the confidence interval around very systematic relation. My question is earlier if you look at flashcards as an example of like very learning. And so I was wondering why you put it there because I think you have like optimal flashcard strategies involving very systematic. So like flashcard methods will have like do all the flashcards then as you get them right, space them out at greater intervals. It seems like variation with the system anyway. Yeah, I agree. That was just sort of a study on the two and four feet. Probably is not realistic. I think the more variation you can add, the better. And the point about flashcards was not so much about variation, but about testing yourself. Not getting a prompt, letting your mind fill it in. So those are sort of different principles there. Yeah. Just while we're waiting for the end here, anybody who can remember the first 10 presidents? Who was the first? Second? Third? Fourth? Fifth? Fifth? Sixth? Well, Quincy Adams is just a... All right. Seventh? Sixth. Eighth? Ninth? And tenth? Sixth. Look at that. It works. It's weird, but it works. You want to leave the slide or the next one for your... Sure. Very good. One final question? Jake. Jake. So it's reading about language in isolated tribes, and they found that if they were totally isolated, they had a very complex language structure. But if they had a written language, it was a lot simpler. So do you think that complex language was a memory device? That's a really good question. What do you think? Well, after listening to the speech, I think it must be a memory device, because they got to tell stories. That's the only way and pass it on. Yeah. No, this is why storytelling is so much more memorable. It's something we should all build into our talks, because our brain was attuned to stories, and stories are sequences, and there's people in places, and that goes to our hippocampus. It's tapping into ancestry, and it's tapping into the structure of our brain. All right. We have three more minutes to promote... Any more questions? Go ahead. About the mechanisms of how the movement... Not exactly, but obviously the Aboriginal Australians figured that out. But what I did read about actors memorizing their lines, they did say that this was a key piece to add some gesture inflection movement because just reading your lines monotone doesn't have that same effect. So it's integrating movement, body, and the whole person. Actually, I think that an answer to that is partly that the centers of the brain that are involved in speech production are also those that are involved in movement coordination and dance and music performance. So I think you're... And that's why people who are deaf use sign language so readily and so easy to use, and actually the language system is doing that. But I think you're using multiple systems at the same time there's redundancy and that contributes to bolstering the retrievability later. What's the etiology of the word hominesis? Oh, very good. I don't actually know the etiology of that. It does come from, I think, a Greek term. Anybody here who knows the etymology? I don't. I was going to tell you something else. Yeah. Okay. But it is... I will say one thing. It's often confused with homeopathy. Nothing to do with it, right? Please. I talk about it. They go, oh, homeopathy. No, no, no, no, no, no. It's low-dose stress. And by the way, it is studied. It is a biologically studied phenomenon in toxicology. Edwin Calabresi has published studies of hundreds of different examples in toxicology of substances that are toxic at a high dose but are actually beneficial at a low dose. There's elements like copper and zinc, right, which we need at some level but are toxic at high levels. I think the same thing is true of, you know, exercise of a lot of other things. Yes. So a rapid motion eagerness to set in motion L. Burgeau and Martin. There we go. One more question over there. I just wanted to take on to the learning where you're doing some movement in the Waldorf school system. You're learning the time students employ bean bags or wearing them on their head walking around the ballot. So I think it's a kinesthetic. Kinesthetic, yeah. And their staffs couldn't recognize faces and they know somebody else who doesn't. So I'm wondering if you have anything to say about that. You can't recognize that uniqueness of the face able of the mouse. Yeah, what is it called? Anagnosia or something like that. Yeah, I think it's probably damaged to those face cells in hippocampus, you know, at some level. Yeah. Yeah. Okay. Thanks. Thank you very much, guys. So now we have a 10 minute break to stretch your legs and remember everything from this talk and go practice it in your mind palace and please come back here in 10 minutes at 9.50 for the next talk. Thank you. Don't go far. That may all be. Hi.