Welcome to the Huberman Lab Podcast, where we discuss science and science-based tools for everyday life. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today, we are discussing how to study and learn.
That is, what the scientific data say is the best way to study in order to remember information and to be able to use that information effectively in different areas of your life. So for those of you that are still in school, this could be any stage of school, today's discussion will be very useful for you. However, even if you are not formally enrolled in any kind of school at the moment, today's discussion will also be extremely effective for you to be able to study and learn better information from say the internet or podcasts or any area of your life where you are seeking to learn and use new knowledge. Now, one of the most important things that you're going to learn today is that learning, that is the best learning practices, are not intuitive. So before we dive in, keep in mind that whatever you believe about how best to learn for you is probably incorrect.
And I confess this was humbling for me as well when I started to dive into this literature, because as somebody who was a student for many years and in some sense still considers himself a student of Science and health information because of this podcast, and certainly as somebody who still teaches university courses, both to medical students and graduate students and to undergraduate students at Stanford, I thought I understood the whole teaching and learning process, but I too learned that it is anything but intuitive. In fact, most of what we believe about the best ways to study are absolutely false. Fortunately, today you will learn the best ways to study.
Turns out there's a rich literature on this. dating back well over a hundred years, and the data are absolutely fascinating and incredibly actionable. It's incredibly interesting how the fields of education, the fields of psychology, and the fields of neuroscience have now come together to define the optimal strategies to study and learn. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero cost to consumer information about science and science-related tools.
to the general public. In keeping with that theme, I'd like to thank the sponsors of today's podcast. Our first sponsor is Eight Sleep.
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Today's episode is also brought to us by Waking Up. Waking Up is a meditation app that offers hundreds of guided meditation programs, mindfulness trainings, yoga nidra sessions, and more. I started practicing meditation when I was about 15 years old, and it made a profound impact on my life. And by now, there are thousands of quality peer-reviewed studies that emphasize how useful mindfulness meditation can be for improving our focus, managing stress and anxiety, improving our mood, and much more.
In recent years, I started using the Waking Up app for my meditations because I find it to be a terrific resource for allowing me to really be consistent with my meditation practice. Many people start a meditation practice and experience some benefits, but many people also have challenges keeping up with that practice. What I and so many other people love about the Waking Up app is that it has a lot of different meditations to choose from.
And those meditations are of different durations. So it makes it very easy to keep up with your meditation practice, both from the perspective of novelty, you never get tired of those meditations, there's always something new to explore and to learn about yourself and about the effectiveness of meditation. And you can always fit meditation into your schedule, even if you only have two or three minutes per day.
in which to meditate. I also really like doing yoga nidra or what is sometimes called non-sleep deep rest for about 10 or 20 minutes because it is a great way to restore mental and physical vigor without the tiredness that some people experience when they wake up from a conventional nap. If you'd like to try the Waking Up app, please go to wakingup.com slash Huberman where you can access a free 30-day trial. Again, that's wakingup.com slash Huberman to access a free 30-day trial. Okay, let's talk about how best to study and learn.
And of course... people have different learning styles. Some people prefer to learn by reading.
Some people prefer to study in a group. Some people prefer to highlight. Some people call themselves auditory learners.
Other people consider themselves visual learners. But guess what? When one looks at the research on preferred learning styles, pretty much all of that melts away.
It turns out that the best way to study and learn is defined not by the medium in which that material arrives, whether or not it's... auditory or visual or combined, whether or not you review slides or a textbook or you watch small videos, it turns out that the best way to study and learn is to access components of your memory systems that offset forgetting. This is a theme I'm going to return to over and over again throughout today's episode. Rather than think about studying to learn and retain information, I want you to think about studying to offset the natural process of forgetting that everybody experiences when they are exposed to new material of any kind, cognitive or motor learning, musical learning, math, et cetera.
Okay, so keep this in mind throughout today's episode. The best way to learn is to think about offsetting the natural forgetting of new information. You're trying to inoculate against forgetting. That is the way to remember things, that is the way to gain mastery over them. And I'm going to teach you how to best do that using the data gleaned from the peer reviewed literature.
Now, before I do that, I want to talk about what learning is. I promise to make this fairly brief because I've covered learning and so-called neuroplasticity before on this podcast. For those of you that have heard those discussions, this will serve as a refresher. For those of you that have not heard those discussions, This will be thorough enough for you to be able to digest all the rest of today's information.
Neuroplasticity is this incredible feature of your nervous system, which of course includes your brain and your spinal cord, which is the ability for your nervous system to change in response to experience. So any form of learning, involves neuroplasticity. Neuroplasticity, we sometimes hear as neuralplasticity, two words, or neuroplasticity. Those are the same thing, essentially. The change that underlies neuroplasticity at the level of cells, which we call neurons or nerve cells, generally involves three different mechanisms.
One is the strengthening of certain connections, what we call synaptic connections. Synapses are the location between neurons where they communicate with one another. It's actually... between the neurons. It is technically called the synaptic cleft.
It's a gap. And within that gap, chemicals are passed across that gap that allow one neuron to activate other neurons, or many neurons to activate many other neurons, or to inhibit the activity of other neurons, okay? So one form of neuroplasticity is the strengthening of connections between neurons. Another form of neuroplasticity is the weakening of connections between neurons. And yet a third form of plasticity, which is often discussed in the media, but is very rare actually in the nervous system, especially the adult nervous system of humans, is neurogenesis or the addition of new neurons.
Let's just get this out of the way upfront because the addition of new neurons, again, grabs so much attention in media articles, but it's responsible for a near trivial amount. Of the sort of neuroplasticity that is important for today's discussion, or frankly, for most all discussions. It is true you have a specialized set of neurons in your olfactory bulb that are responsible for smell, as well as a specialized set of neurons in the so-called dentate gyrus of your hippocampus, an area of the brain that's important for memory, in which new neurons appear to be added throughout the lifespan. But this is not the major mechanism by which learning and memory occurs in humans. Rather, The major mechanism by which learning and memory occurs in humans is the strengthening of existing connections and the weakening of existing connections or the formation of new connections between already existing neurons, not new neurons, okay?
Now, the removal or weakening of connections between neurons being an important component of neuroplasticity is very important for sake of today's discussion. I want to emphasize that when we hear about weakening of connections, we often think, Well, that means forgetting, or that means the brain is getting less good. However, so much of the neuroplasticity that underlies, for instance, the acquisition of a new motor skill is actually the reflection of removal of connections. So we don't want to project any kind of value onto a discussion about adding new connections, removing new connections.
Let's just leave it at this level mechanistically. When you hear about neuroplasticity, just know that it could be the consequence of strengthening of connections as well as weakening of connections. And that neither strengthening of connections in the nervous system nor weakening of connections can map directly to the formation or removal of say memories or information.
Just know that these are the important mechanisms. In fact, if you look at a baby that is, let's say, I don't know, nine months old, their motor skills are not terrific typically. compared to the motor skills that that child will have when they are six or seven years old. Just look at a kid trying to eat spaghetti or something of that sort, or eat anything when they're a small baby versus a toddler versus a young child versus an adolescent or teen. You know, despite the poor table manners of some adolescents and teens and some adults, for that matter, they are still exhibiting far more precise motor movements than they did as an infant, of course.
And believe it or not, The improvement in motor coordination that one observes in humans and other species for that matter, from birth until the adolescence and teen years and adult years is largely the reflection of the removal, that's right, the removal of neural connections as opposed to the formation of neural connections. However, the neural connections that remain become much more robust. They become much more reliable.
Okay, so that's the mechanistic backdrop for everything that we're going to talk about today, which is how to study and learn. And as I mentioned earlier in my introduction, most of learning and remembering new material is about offsetting the forgetting process that naturally occurs anytime we hear new information. So in keeping with what will ultimately reveal itself to be the dominant theme of today's discussion right now, and for reasons that will become clear later, I want you to take a brief quiz.
Now, the moment people hear quiz or test, typically it spikes their adrenaline, they start feeling stressed, but don't worry, you're going to keep your answers to yourself and you're doing this for a very specific purpose. Here's my question. This is a two question quiz. How many different ways, mechanistically speaking, does neuroplasticity occur?
Is it one mechanism, two mechanisms, or three mechanisms? Or is it four or five? Okay, can you name in your head two of the three major changes that the nervous system can undergo which are reflective of neuroplasticity?
Okay, so the answer to question was? is that there are three different modes of neuroplasticity, as you recall, or as you may not have been able to recall. And by the way, if you were not able to recall the three different modes of neuroplasticity or mechanisms underlying neuroplasticity, that is fine. As you'll soon realize, recognizing the errors in your information retention is another critical and very useful way to retain more information, even if you got the answer wrong or you didn't know.
In fact, especially if you got the answer wrong or you didn't know. So the three ways are the strengthening of neural connections, second, the weakening of neural connections, and third, through neurogenesis, the addition of new neurons. Why did I provide this quiz? Why did I test you? Well, as you'll soon learn, if you look across the total body of research on how best to study and learn, it involves doing exactly what we just did, which is to periodically stop and test yourself on the material that you learned.
Testing is not just a way of evaluating what knowledge you've acquired and which knowledge you have not managed to acquire. It also turns out to be the best tool for offsetting forgetting of any kind. And I'll go into the data that supports that statement in a moment. So yes, today we're going to get a little bit meta in the sense that we're going to be learning about optimal studying strategies and applying those as we go through this podcast.
And no, there will not be a test at the end, although you're welcome to give yourself a test at the end. I'm going to provide you with an excellent zero cost, very fast tool that you can use to evaluate your knowledge and your ability to study and learn better as a consequence of having listened to this podcast versus had you not listened to this podcast. So if ever there was an incentive to listen to the end.
There it is. Okay, let's talk about some of the other practical aspects of studying and learning. I know a lot of you out there who want to learn and want to come up with the best studying strategies are trying to think about how to structure your day or how much to study or when to study.
Let's get the most important things out of the way first. Neuroplasticity and learning, that is converting your studying efforts into retention of knowledge is a two-step process. You've probably heard about active engagement. That's just a fancy set of words for focus, for really attending to the information that you're trying to learn.
And it is very important anytime you're trying to learn new information. So focus goes with alertness. You can't be focused if you're not alert.
This is prerequisite. So you need to be alert and you need to be focused in order to pay attention to the information that you're trying to learn. In fact, it is the process of being focused and attending that.
Cues your nervous system that something is important, that something's different about whatever sensory experience you happen to be having when you're focused and attending, whether or not it's the information you're hearing or that you're looking at or both. That cue at the level of neurochemicals in your brain and body signals to the neurons, hey, you're going to have to change. You're going to have to alter your connections, either make them stronger or weaker or a combination of those things in order to make sure that your nervous system can retain and use the information at a future time. So that's step one. And of course, as a part of step one, most people, when they hear about optimal studying strategies, they want to know, you know, what should they do?
What should they take in order to learn better? Well, here's what everyone should take in order to learn better, which is a great night's sleep the night before, limiting your external stress. Although some stress is good because it cues up your alertness. It actually allows you to remember certain things better. We'll talk about this a little bit later.
No one can remove all stress from their life, but we know one thing for sure, your ability to be alert and focused is going to be greater if you slept well the night before. Okay, so sleep is without question the best nootropic, right, the word nootropic means smart drug. I don't really like that term because learning involves all sorts of things.
It's not just about being smart, it's about being able to attend. It's about sometimes being creative, flexible with ideas and information. Here's the point, you're going to need to get your sleep right. in order to be able to study and learn at your absolute best. And I've done many episodes of the Huberman Lab podcast about sleep.
We have a newsletter about sleep, the details in a short PDF format, the various things you can do to get your sleep optimized, so to speak. You can find all that at hubermanlab.com by putting sleep into the search function. We don't have time to discuss that material now, but get your sleep right so that you can be alert and focused when it comes time to learn. Now, The process of being alert and focused on particular material that you want to learn can be enhanced by just having a silent script within your head, silent meaning you're not saying it out loud, where when you sit down to learn, you're looking at a book or you're listening to a lecture, perhaps a podcast like this, you're thinking, okay, I need to learn this, I need to learn this. You can voluntarily ramp up your level of focus and alertness by telling yourself that information is important.
Don't be a Passive participant in learning, this is the basis of active learning, by expecting the information to be so interesting that it pulls your level of attention and focus out of you. Rather, learn to engage your attention and focus voluntarily, volitionally, okay? When we hear about ADHD, attention deficit hyperactivity disorder, we know that people with ADHD can attend very rapidly. They can really pay close attention for long periods of time if they like a given topic or a given experience or activity. They have serious challenges, however, engaging their attention and alertness if they are not excited about an activity or information.
And so it is the hallmark of all good learners to be able to voluntarily force yourself to attend and to focus. And when I say force yourself, that means a constant bringing back of your mind's attention to whatever it is you're trying to learn. It is meant to feel. Difficult.
I say meant to feel difficult because that strain that you feel, that encouraging or in some cases, forcing yourself to attend, sometimes even putting on a hoodie and hat, literally putting blinders so that you can only attend to the material right in front of you, that straining that you feel reflects in part the release of neuromodulators like epinephrine, adrenaline in the brain and body, which serve to cue the neural circuits that they need to change at a later time. Okay, so the strain that you feel in trying to learn, the strain that you feel in forcing yourself to learn how to focus, that is good. That's a Q-tier nervous system that it's going to need to change, that neuroplasticity needs to take place. Think about it. If you didn't feel that strain and you were able to perform whatever it is that you were doing, or remember whatever information it is that you're being exposed to seamlessly, well, then your nervous system wouldn't have to change because it already has the capabilities within the neural circuits.
So that strain that you feel, that agitation is great. That's a cue that you are learning or that you've set the learning process in motion. Now, it's also the case that some people don't have great levels of focus and attention. And there are, of course, pharmacologic tools. I would encourage anyone that has clinically diagnosed ADHD to talk to their doctor about whether or not they should use prescription meds and or other methods.
Great sleep is always going to be an important substrate for attention and focus for anybody, but especially for people with ADHD. I highly encourage anyone that's interested in enhancing their levels of focus and attention to also consider the non-pharmacologic approaches. So this is irrespective of whether or not you need pharmacologic approaches. Yes, being well hydrated. Yes, the appropriate amount of caffeine for you that allows you to be alert, but not shaking and agitated can be very useful.
However, the scientific data also support the fact that doing a brief, say five to 10 minute mindfulness meditation each day, these are the data from Wendy Suzuki's laboratory at New York University, showing that people who do a 10 minute meditation per day where they simply sit or lie down, close their eyes, focus on their breathing, their attention invariably drifts, they bring their attention back to their breathing. People who do that on a regular basis improve. their level of focus, they improve their memory and recall ability.
And of course, there are a bunch of other positive effects of that simple zero cost tool of mindfulness meditation. So if you're interested in improving your levels of focus and attention for sake of learning, I highly encourage you to explore the oh so valuable tool of mindfulness meditation, just five or 10 minutes per day done on a regular basis. You miss a day, no big deal, just get right back to it the next day. Does it matter if you do it morning, afternoon, or night? No.
Some people find that doing it too late at night might disrupt their sleep. But if you think about meditation of the sort that I just described as a perceptual exercise, maybe you don't even call it meditation, you're just teaching yourself to focus. You could even do it with eyes open by focusing on a visual target, allowing yourself to blink. There are good data on this sort of approach as well.
And then just making sure that your visual attention and cognitive attention comes back to that visual target. Over and over again, it's a deliberate process of bringing your attention back to a particular location. That is very valuable for improving your levels of focus. In fact, it is known to create significant improvements in your ability to focus, which is critical for your ability to study and learn.
So I know that many people are interested in what to take, what to do at the level of kind of esoteric practices or things to buy. There is stuff out there. Again, I mentioned hydration, caffeine, great sleep, and so on, but the simple practice of mindfulness meditation or just what I describe as a focusing perceptual exercise of bringing your attention back to the same location over and over again deliberately will train you to train your nervous system to bring your attention back to whatever it is you're trying to learn.
Now, I've done other podcasts about how to focus about attention specifically and ADHD. Again, you can find all of those at hubermanlab.com. Simply put ADHD or focus or tools for focus into the search function, and it will take you to the exact timestamps in those episodes that are relevant.
Right now, however, I want to talk about the second part of neuroplasticity, which is that the actual changes in the nervous system, the strengthening and weakening predominantly of connections between neurons that underlie learning do not occur during the focusing and learning, or rather the exposure to the material, but instead during deep sleep and sleep-like states. And again, I've done a lot of podcasts and talked a lot about tools for getting better sleep, but I just want to remind everybody that the actual reordering of the connections, the strengthening of connections between neurons that underlie learning, the weakening of those connections occurs during sleep, in particular during rapid eye movement sleep, which tends to predominate in the latter half of the night. So make sure that you're getting enough sleep for you. For some people it's six hours, for some people it's eight hours.
And yes, there is something called the first night effect. The first night effect is the experimentally observed phenomenon whereby information that you learn on a given day, Is mostly consolidated during the night sleep that you have on that first night after the learning occurs. Does this mean that if you get a poor night's sleep on the first night after learning something that you are forever going to forget that information, that it cannot be consolidated into your neural circuits? No, however, it's very clear that the first night after learning, you want to get the best sleep possible.
So if you're learning bouts, you're studying, is going late into the night and you're drinking a lot of caffeine, be mindful that the sleep that you get after drinking that caffeine late into the day, the all-nighters that you're pulling, those are not serving your learning well. So you need to structure your life as a student of any kind so that you can get focus and attention to what it is you want to learn, and you can get sleep to the best of your ability. And of course, people who are raising young kids or who have stress in their lives for whatever reason, perhaps won't be able to optimize their sleep.
on that first night or even subsequent nights, but do your best to get your sleep right. It's the single best thing you can do for your mental health, for your physical health, and for learning and performance of any kind. And it's really worth the effort.
Now, with an understanding of the mechanisms, the focus and alertness, and the sleep phase of neuroplasticity, what are some other things that you can do to enhance whatever studying and learning you've obtained? I already talked about a tool, a behavioral tool for enhancing focus. What about a behavioral tool for enhancing plasticity if your sleep is great, or especially if your sleep isn't great?
And there, I highly recommend you explore non-sleep deep rest or NSDR. There's a script for this in the show note captions. NSDR, sometimes referred to as yoga nidra, although those things are similar but different, is a 10 or 20 minute practice that you can do to restore your mental and physical vigor. if you haven't slept enough. So you could do it first thing in the morning when you wake up, if you feel you haven't slept enough.
You can do it in the afternoon. You can do it in the middle of the night if you're not able to sleep and offset some of the sleep loss that you otherwise would have experienced. NSDR is a very powerful tool in order to enhance neuroplasticity.
And I'll talk more about this in a future episode. There's a lot of exciting data coming out about NSDR and yoga nidra. But if you're sleeping well, and even if you...
I highly encourage you to incorporate a 10 or 20 minute NSDR into your schedule someplace. Again, where you place it in your schedule isn't as important as the fact that you do it in order to enhance neuroplasticity. That is the reordering of connections between neurons to serve the studying and learning that you're doing.
Now let's talk about how the best students structure their days. Turns out there are great studies on this. There's a really nice paper, in fact, that surveyed close to 700 students.
These were medical students. approximately equal number of male and female students and analyze the most useful learning habits. That is the learning habits associated with the most successful students.
Now, anytime you do a study like this where people take surveys, there's always the issue of causality. In fact, we can pretty much set aside any possible causality. For instance, I'm about to tell you that the very best performing students tend to study for about three or four hours per day, but you could easily say, well, they're the best students because they study three.
or four hours per day. They don't study three or four hours per day because they're the best students, and you'd be exactly right, okay? We can get into all sorts of discussions about correlation versus causation, about reverse causality, and on and on.
However, none of that is the point here. The point here is to establish what are the habits that the most successful students seem to incorporate over and over again, regardless of what classes they're taking, regardless of where they are in their arc of their learning trajectory. And so what we know based on this study, and I'll provide a link to it in the show note captions, is that there are at least 10 study habits that the highly effective students use.
I'm going to focus on the top five or six just for sake of time, because it turns out that most of the effect, it appears, of being a better student can be attributed to these top five or six habits. First of all, they set aside time to study. They literally schedule time to study.
Now this probably serve several roles. The first one is that they are able to clear out other distractions. And in fact, that's the second thing that they do. They are very effective where they make it a point of putting their phone away and off, of isolating themselves. That's right.
They're not studying with other people. They study alone, which is not to say that people who study with others cannot be effective in their studying, but the best performing students seem to study alone. They put their phone away.
They tell their friends. and families that they are not going to be able to be reached during that time. And yes, they study for three or four hours per day, but they break that up into a couple of different sessions typically, two or three sessions. So they're not doing a three or four hour studying about all in one shot.
So they're managing their time, they're eliminating distractions, and they're studying for a consistent amount of time, at least five days per week, okay? Presumably they're taking some weekends off, although that wasn't made clear from this paper. The other thing that they do, and this is very important, is that they make an effort to then teach their peers, to teach other students in the class. Now, some of you may be thinking, and I'm thinking back to college here, mostly, that if you spend all this time learning the information and you are in a competitive scenario with the other students, that teaching them the information is kind of a freebie for them and it's harder for you, meaning you're putting yourself at a competitive disadvantage or you're giving them an unfair advantage.
for not having done the work. Now, while this paper didn't do an analysis of whether or not these students that served as the learners from the other students got an unfair advantage, it's very clear that students who make it a point to learn material in isolation, then bring that material to other students in the same course and teach them, perform exceedingly well in comparison to the other students. So don't be afraid to be a teacher of your peers in order to test, this is key, to test and Develop mastery of the material.
Now, in my laboratory for years, we used to have a saying, which I simply picked up from the laboratories I was trained in, I didn't come up with the saying, which was watch one, do one, teach one. And that was referring to doing surgeries or suturing or doing an antibody reaction or a Western blot or things that you do in laboratories. Watch one, do one, teach one.
Watch one, do one, teach one, of course should be reserved to anything where no one's going to be put in danger. by the watch one, do one, teach one procedure, right? Some procedures, especially in laboratories, can be dangerous given the materials you use, et cetera.
And of course, today we're talking about learning and studying generally. So provided it's safe, watch one, do one, teach one, is an excellent means to learn, that is to study new material, to develop proficiency and even mastery. And over time, perhaps even virtuosity. We'll return to that later, those distinctions.
So going back to this idea that the best students set aside time, they designate time to study alone without distractions, that is sure to help them anchor their focus and attention. They know that they're going to need to use their focus and attention during that time. And we know with absolute certainty that focus and attention are a limited but renewable resource. In the human brain. The longer you're awake, the more is the buildup of a molecule called adenosine in your brain and body.
It makes you sleepy, makes it harder to focus. When you sleep, adenosine levels are pushed down again. You're able to focus again. You feel more alert.
You can think of adenosine as limiting your attentional budget, which is not to say that some people don't study best in the afternoon or in the evening, or even late at night. Right? I recall times during university when I'd study between the hours of 10 PM and 2 AM.
I don't do that any longer, but. Scheduling time where you know you're going to need to be focused and attending is perhaps one of the most important things toward being able to focus and attend to the material. Now, if you're taking courses, you probably are going to be a slave to the timing of the courses.
You aren't going to be able to tell the instructor,"'Okay, listen, I want you to do this course at 3 p.m. because that's when you learn best, or at 8 a.m. because that's when you happen to be able to attend best.'" However, to the extent that you have any control over the time in which you're going to study, keeping that at a regular time or times, perhaps one block early in the day, one block later in the day, perhaps two blocks early in the day and so on is going to be beneficial. It turns out that's also supported by the research literature, that the brain, just like with its sleep-wake cycles that entrain to a regular schedule, that is your brain and body get used to being active and inactive at particular times based on your exposure to sunlight, your exposure to activities, your social rhythms, et cetera. If you regularly, meaning for the course of about three days make it a point to focus and study at particular times, again, pulling your attention back, it's not an automatic process, but pulling your attention back to a specific location, perhaps on a page or that you're listening to in a lecture, your body and brain will start to entrain to that rhythm such that you will be able to focus and attend better simply by virtue.
of the regularity of the timing of the exposure to the material, okay? So you probably need about two or three days to break into a regular schedule of focusing and attending and studying at a given time or times. Allow yourself that transition period, but then make it a point to schedule those times to study, set aside your phone, tell people you're going offline, turn off the wifi if you need to or have to. You may need it for your studying, I don't know.
Depends on what you're studying, but- but limit distractions at all costs and learn to just focus on the material. And this is a skill. This is the most important thing to understand. It's a skill to be able to focus and study.
And it's a skill that you can learn very quickly, especially if you schedule it for regular times and you give yourself two or three days in which to adapt to those schedules and times and then try and stick to them as regularly as possible. Perhaps even on the weekends, if you're approaching the end of the quarter or semester. perhaps even on the weekend, even if you're not in the quarter of semester.
Keeping those regular times will entrain your nervous system to study and learn at its best at those particular times. I'd like to take a quick break and acknowledge our sponsor, AG1. By now, many of you have heard me say that if I could take just one supplement, that supplement would be AG1.
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Right now, they're giving away five free travel packs plus a year's supply of vitamin D3K2. Again, that's drinkag1.com slash Huberman to claim that special offer. Before I move into specific ways to study in order to maximally offset forgetting, notice I didn't say in order to learn, but rather to maximally offset forgetting, AKA learning, stably learning material.
There's one other point that I wanted to pass along from this really nice study on the study habits of highly effective medical students that I've been referring to. And that is when one examined or these people were asked about their motivation for studying. The best performing students had an interesting answer.
They had a very long-term understanding of how, or belief rather, about how their success in medical school would impact their family, how it would impact their life arc, how it would change them. And they weren't particular about the ways in which it would change them or their family. In fact, it was a rather broad, abstract, aspirational way of thinking about their study efforts.
So what I like so much about this paper is that, you know, in addition to having a fairly large sample size, close to 700 students that were evaluated, and yes, it's purely, you know, self-report and this kind of thing, nonetheless, it bridges the two extremes of studying and learning. You know, it gets right down into the nitty gritty of how long they study, when they study, the things they do to limit distraction that we just discussed. but it also gets to their underlying psychological motivations and the thing that they use in order to pull them forward through their study efforts, perhaps especially when their desire is waning or their level of fatigue is increasing.
I don't know that I'm speculating here, but this is this aspirational component of going to medical school, which it turns out in the country in which the study was done, only very, very select few of the very best students are able to achieve that. And they have to learn the information in a different language altogether, which is incredible. I always marvel at that. I have friends that did their PhD thesis in Italy.
They're Italian by birth. They now happen to run a laboratory in Italy. And they had to do their PhD training and write papers and give their thesis dissertation and defense in English, even though English was their second language.
So talk about a challenge. And that's just one example that I. can think of. There are many examples of that.
These students that I'm referring to in this study are not necessarily constantly thinking about how their efforts will transform themselves and their families, but they certainly were able to report what it was specifically that they are seeking, what they're aspiring to, besides just trying to do as well as they can getting into and through medical school. So the high-level aspirational stuff within you, whatever that is for you, it's going to be highly individual, is certainly important. And it offers a bookend to the nuts and bolts-y kind of stuff that you're going to do, I would hope, in order to best study and learn the specific material. So the specific actions that you're going to take each day to learn specific bits of information that will pull you toward those important aspirations. And now again, if you love the material you're learning, This aspirational component is probably not as important, right?
I can recall during university and graduate school and so on thinking, oh my goodness, this is like the coolest thing I've ever heard. I've probably say that about a million different topics. Oh my goodness, circadian rhythms, seasonal rhythms, melatonin, neural circuits, dopamine. I was just awash with excitement about what I was learning. But of course, sometimes I would take a course where the material was, I don't know if it was more challenging or not, but I had a harder time getting engaged by the material, either by virtue of how it was being taught to me or the material itself.
So the ability to attach to some aspirational goal to pull you through can be very valuable. You're not going to love every topic you have to learn. However, I will say that at least in my experience, some of the courses that I look back on most fondly are the courses that I struggled with the most.
And in fact, that's the basis of the next and easily one of the most important studying tools. So a key theme in all, of the excellent literature, that is the peer-reviewed research on how best to study, is that studying that feels challenging is the most effective. I know nobody wants to hear this. Everyone wants to hear about flow. Everybody wants to hear about information just sinking into their brain by osmosis.
I think it was a Garfield cartoon where he talked about learning by osmosis. There's this very cute real world video of a kid in a classroom. I believe it's in China where he's taking the book and he puts it on his head.
Maybe I can find this clip and he's just kind of like trying to wash it into his brain. It's super cute clip, but guess what? That doesn't work. I mean, it works to put the book on your head.
It doesn't work to, it's not going to get the information into your brain. Perhaps someday there will be ways to rapidly download information into neural circuits. Right now we know. We've known for hundreds, if not thousands of years, that effort is the cornerstone of learning.
So I know there are probably some groans about that. I know some of you perhaps were hoping that today I was going to tell you how to study so that studying wasn't painful. I think I can accomplish that by the end of today's episode, but in order to do that, Let's take another quiz.
Okay, so here's the quiz. Again, you can answer these questions in your head. You don't have to tell anyone, but you could write them down or say them out loud if you want. The first question is...
When during either your states of alertness or sleep does the remodeling of neural connections occur? I like to think this is a pretty easy one. Okay, the answer is during sleep.
The second question is what is one behavioral tool that you can use to improve focus? The answer is simple mindfulness meditation, which I'd prefer you think of simply as a perceptual exercise. So again, just sit. or lie down, close your eyes, focus on your breath when your attention drifts, bring your attention back to your breath and so on.
Or if you prefer, you can do this eyes open by focusing on a visual target, either a foot or two feet or three feet away, whatever distance is comfortable for you, allowing yourself to blink as needed, but forcing yourself to focus on that visual target for say one to three minutes, maybe even three to five minutes, maybe even 10 minutes. Again, please blink. You don't want your eyes to dry. Both those tools will improve your ability to attend, to focus, to other material when the time comes, okay? The circuits for focus and attention themselves are subject to neuroplasticity.
And then the third question is, can you name or list off in your mind three tools that the most effective students have been shown to use? I can think of... Limiting distraction by virtue of putting away phones and telling others you won't be in contact with them too.
And I'm getting these out of order, I realize, is to isolate, to study alone. And the third that I can recall is to teach others in the same course, okay? You can probably think of a few others. Now, why are we taking these silly little quizzes?
Well, turns out they're not so silly. When one considers that hopefully you'll remember the information from today so that you don't have to listen to it over and over again, but that if ever there was a strongly research supported tool in the literature, in the peer reviewed literature about how students can learn information better, it's testing. And I know, I know, I know we think of tests. as a way to evaluate our knowledge.
But it turns out that testing is one of the best ways to build our knowledge, to retain our knowledge, and again, to offset forgetting. Now, the study of testing as a learning tool, not just as a way to evaluate how much information we've learned, goes back over a hundred years. There's a classic study that was done in 1917 where grade school age children read biographies. So they read biographies and then the kids were divided into different groups.
One group read and reread and reread those biographies over and over. Another group read the biographies once and then were tested on those biographies. But get this, they tested themselves on those biographies simply by having to think about the information that they had read and trying to remember the information. Like what was the biography?
Who was the person? Who were they married to? What did they do?
When did they go to school? What did they do in school? What did they do in the world? What... role did they play in life?
So they essentially tested their own knowledge simply by going into their own head and asking themselves what they could remember about those biographies. Now, keep in mind here that even though it's fairly apparent that reading a biography two, three, four times might seem more passive than testing oneself on a biography that they had read just once, right? You could imagine that.
thinking about the biography involves more effort, and indeed it does. But keep in mind also that the kids in the second group were only exposed to the biography once. And yet, when you look at the percent of accurate recall of information from those biographies, the children that read the biography once and then made a deliberate point to think about that biography in their own mind to effectively test themselves on that material just within their heads. over and over, but an equal number of times as the kids that read the biographies directly on a page over and over, vastly outperformed the kids that read the biographies over and over.
Put differently, reading and rereading material and rereading material is far less effective than reading material. and then thinking about that material, testing yourself on that material, forcing yourself to bring that material to mind in your own mind. And this is not just for sake of remembering more volume of material, but also accuracy. of recall of that material. And that at least to me was pretty surprising at first until one starts to explore subsequent studies of the role of testing as a learning tool.
And then you start to realize that testing yourself is far and away the best tool for studying and learning, not just for evaluating your knowledge, but for actually studying and incorporating that knowledge into your neural circuits. Okay, so I realized that anytime I or somebody else talks about a study that was done in 1917, we think of people in these, you know, like wooden shoes and in these school houses that look so different and kids dress so different. Let's get a little more modern here.
Keep in mind, however, that the nervous system hasn't really changed much in tens of thousands of years. Nonetheless, I think it's nice to think about a more recent study of how best to study. And this study.
which by the way, we'll provide a link to in the show note captions, as well as a couple of reviews that include results from similar studies. Again, I'm pointing to a body of research, not just one study here. Looked at whether or not studying material four times, so study, study, study, study, was better in terms of locking that information into people's minds. allowing them to use that information flexibly, which is an element of creativity, essentially giving them mastery of the material.
Then a different group, which studied once, studied the material twice, studied the material three times, then was tested on the material. Or a third group that studied material once, then took one, two, yes, three tests on the material. Now, so what I just described was three groups, all of whom read a passage.
This was a passage about animals, about biology, some other topics too in different experiments. Again, three groups, one group studies four times. They study the material one, two, three, four times.
Then later they take a test. The second group studies one, two, three times, takes a test on that material, and then later takes a test. The third group studies the material once, then takes three tests on the material.
and then later takes a test. So what's analyzed and compared between these different groups is their performance on that final test, okay? What I put in as the fifth bin there, right? Because it was, think about it as SSSS, so study, study, study, study, and then later test, or SSST, study, study, study, test, and then later test, or STTT, study, test, test, test. and then later tests.
So what's compared and contrasted is performance on the test some period of time later. Now, some experiments made that final test of the material a couple of days later. Other experiments made it a couple of weeks later. Other experiments made it much later, months or even a year later, okay?
The point here is twofold. First of all, Based on everything I've told you thus far, you can probably guess who performed best on the test that occurred some period of time later, okay? Right, the performance on that final test was essentially proportional to the number of tests one had already taken on the material.
Okay, that should be pretty much obvious given the way we've been going today in this description of tests as a way to offset forgetting. Okay, so the more tests that you take as a way to expose yourself to the material, the better you're going to perform on that material at some later point. Now, of course, at some point, you have to be exposed to the material for the first time, right, that's why it's studying and learning.
But after one exposure to new material, taking more tests on that material, even if you don't perform that well on those tests, as long as you're able to see the accurate answers to those tests and compare your answers to those answers will lead to better performance on the ultimate test and retention of that material at some later time. Put differently, it's not about how many times you study the material or how many times you're exposed to the material. It's about being exposed to the material, doing your best to focus and attend to that material, and then self-testing yourself on that material.
Or as the case may be, if an instructor is the one giving you the test, but nonetheless taking tests on that material, not just once, but ideally two or three times, that's what really locks the material. into your neural circuits. That's what's going to lead to the most pervasive change, the most durable change, we should say, in your neural circuits that carry that material, that hold that material in your mind, what we call neural encoding, okay?
So. The more times you test yourself or that you are tested on material, the better your retention of that material. Now, some people will immediately say, well, goodness, what if I learned it and then I'm tested and I'm somehow consolidating the wrong or inaccurate material?
But it doesn't appear to be the case. As long as you learn what the correct answers to the tests are, even if you're getting 40 or 50% or less accurate on those tests that you take immediately after the studying period. That's still going to be a better strategy than rereading the material, which ought to be somewhat surprising. It certainly was surprising to me, but you know what's even more surprising and a little scary and that we all should know, and I wish I had learned when I was like in the second grade is that if you ask students, how confident are you in the material that you just learned?
How well do you think you would perform on a test? What you see consistently in these studies, I'm chuckling because it's kind of mind blowing is that the students who studied the material, that is who were exposed to the material four times, think that they are going to perform best on the ultimate exam. However, the students that study the material once and then are tested three times on that material, they think that ultimately they're going to perform least well.
For instance, they ask them their confidence. How well do you think you would perform on a test of this material in two weeks? or in a year or in six months, or even tomorrow, they report, that is the students in the study, test, test, test group, report much lower confidence in the material, much lower sense of mastery of the material compared to the students that were exposed to the material four times who are saying, yeah, I think I would do pretty well or very well.
And guess what? The exact opposite is true. Put differently.
When you're exposed to material over and over and over again, you think you've learned the material. In fact, your confidence that you've learned the material increases with each subsequent exposure to the material. But actually, you haven't learned it at all compared to the people that are exposed to the material and then take tests on the material, oftentimes straining to get the answers right on those tests. In fact, sometimes getting those answers dead wrong and then realizing they get those answers dead wrong or sometimes they just sense it. But guess what?
Testing yourself once, twice, maybe three times prior to the ultimate test of your knowledge of that material is far and away the best way to lock that material into those neural circuits. Now I say, I wish I had learned this when I was a student because to some extent I used a self-testing approach. The one most salient example of that is I took a course when I was in college. I still remember it was Biosciences 169L. Neuroanatomy Laboratory taught by Ben Reese.
He's still there, I believe. And he was known then, and I'm sure still now, if he's still teaching, as extremely challenging professor. Extremely challenging, not as a.
a person, not his personality, but a ton of detail and rigor and high, high, high expectation for this laboratory course in neuroanatomy, which involved lectures. It involved in a neuroanatomy textbook where you'd look at essentially panels of different brain sections from different species, different types of stains of different brain tissue. Mind you, this is an undergraduate course. And then there was a laboratory component, hence the L in 169L, where you'd have to go from microscope station to microscope station, identifying structures. based simply on what you could see down the microscope.
And therefore you had to know what the stain was, what was essentially visible to you on the slide, because certain stains reveal certain things like what we call the cell body of neurons versus the sort of wires, what we call the axons between neurons, et cetera, et cetera. I remember thinking, this is a really hard course. It was a very difficult course. And my mode of studying for the course involved, of course, going to class, doing the dissection.
We dissected a sheep. brain at that time. So we're literally dissecting an actual brain. We're doing microscope work. We're learning about it from the textbook and from lecture.
And there was a ton of new nomenclature about rostral, caudal, dorsal, ventral, all the stuff of neuroanatomy. And then at some point I made the decision perhaps on the basis of sheer overwhelm to study for neuroanatomy by laying down on my bed in my Studio apartment, I lived alone, and closing my eyes and flying through the nervous system from different entry points. Through the ear, review my cochlear anatomy.
Through the eye, review my retinal anatomy. Through the dorsal surface of the brain, think about the sulci and gyri, and then the corpus callosum, and I can still see it in my mind's eye. So my process of studying for neuroanatomy, yes, involved exposure to the material, but it involved hours upon hours of thinking about the material within my own. So it's a little bit meta unto itself there.
As a consequence, I like to think, in fact, I believe with some confidence that I have very high mastery of neuroanatomy in different species as well. Now that's my particular area of expertise. I don't think I'm any kind of savant with respect to neuroanatomy. I just spent hours upon hours learning the material and then reviewing the material.
within my mind. So in other words, testing myself, here's what I would do if I were moving down a trajectory of a neural tract, for instance, between say the hippocampus and a neighboring structure and I didn't know what was next, I would then go look it up in the textbook and then I'd go back to this. You know, mental exercise, visualization type studying. It really wasn't studying is the point.
The point is that I was testing myself. I was trying to find the points in which I no longer had the knowledge to move further through, in this case, my mental image of the brain, but through the material. And this is the key aspect of testing.
It's not about just knowing how many things you get right, how many things you get wrong. It's about recognizing exactly what you know and don't know. And an important component of testing is running up against those things where you say, ugh. I can't remember.
I don't know what comes next. Or I'm certain that that structure is the fimbria. And then you go and you look and you go, it's not the fimbria, but guess what? I'll never forget, for instance, the location of the habenula or what it looks like. A structure of which, by the way, since these names are kind of esoteric, at that time, we didn't know what it does.
It turns out it's involved in disappointment. It's key to the depression circuits or the circuits that underlie depression in some individuals. It is suppressed by viewing of morning sunlight.
We know that too. And by getting too much artificial light exposure in the middle of the night, you enhance activity of the habenula. Beautiful work not done by my laboratory, but other laboratories demonstrates that.
So what I just did for you there was hopefully teach you a little something about neuroanatomy and depression, but more importantly, to just illustrate that how you test yourself can be highly individual to the ways in which you learn best. Now that contradicts what I said earlier, which is that this notion that people have different learning styles and, you know, some people are verbal learners and some people are auditory learners and et cetera, doesn't really hold up so well anymore. But which by the way, is not to say there isn't any research to support it. It's just that it's heavily contradicted by other research that contradicts that idea.
But your approach, your mode of best testing yourself on material for sake of offsetting the forgetting process and for identifying where you have gaps in your knowledge or where you thought you knew something, but you don't, or you knew something, but it's wrong. That can be accomplished through the approach that's best for you, which in my case turned out to be lying down and thinking about the material in my head. And still to this day, when I read a paper, I try, I don't always do this, but what I try to do is then take a walk in my yard or outside and I try and think about the key components of that paper and think about some of the graphs that are especially important, which is what I'm gonna do now.
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Let's look at the literature that actually supports that statement directly. Because in the previous experiment I described, it was either study, study, study, study, or study, study, study, test, or study, test, test, test, and then later everybody takes a test at the same time. A variant on that was done where they had one group of students study material.
So this is new material. And when I say study, I mean, they were exposed to the material for the first time. And I realize this is a little bit of a problem because we're using the word study when, in fact, I'm trying to make the point that testing yourself is studying, okay? So forgive me, but this is the way it's mapped out in these experiments and these papers, should you look them up in our show note captions. One group is exposed to the material, what we're called studying, and then takes a test immediately after.
They are told what they got right, what they got wrong on that test, and what the correct answers are. And then sometime later, After a delay, they take a test of the same material. Another group studies, that is they're exposed to the material. Then there's a delay, okay? That delay could be days, it could be weeks.
This experiment has been done every which way, it seems by now. Then they're tested. And then there's another delay.
And then they take a test at the same time that group one did, okay? So again, it's study test, long delay test. for group one or study, delay, test, delay, test for group two. Remember the final test is taken at the same time by everybody or group three study. That is they're exposed to the material, then a long, long, long, long, long delay, then a test and then the ultimate test.
Okay. The test that everybody takes at the same time. Can you guess which group performed best? And the essence of this experiment, if you're listening to this and it's not clear in your mind is you're either exposed to the material and tested very soon after, and then take a test after a delay, say a week or two weeks later, or you're exposed to the material, there's a delay of a few days, then you take a test and then another few days, and then you take a test, so it's more evenly spaced.
Or if you were assigned to the third group, you'd study, you're not going to see the material or be tested on it until A day or two before the big test, then you're tested on it, you get your answers back, and then you're tested on it again. You could imagine that the last group might perform best because they're re-exposed to the material, they're told what the correct answers are, so they know what they got wrong, they know what they got right, and then the next day, they're taking the test again. I would have thought that group would perform best. But it turns out the opposite is true.
It's pretty wild. The best performance comes from being exposed to material, what in this experiment they're called studying. Okay, so they read a passage or they learn some math material or language material or music material or motor learning.
Then they take a test very soon after, even same day or next day. And then there's a long delay. And then they take the test.
That group performs best. Put differently, test yourself very soon. if not the same day, certainly the next day or so, very soon after being exposed to material for the first time, as opposed to the last group, which performs worst. They perform worst. Being exposed to material, then there's a long period of time, then you're tested on that material, you are told what you got right, what you got wrong, and then the next day you take a test again, even with overlapping questions to the test you took just the day before, and that group performs worst.
And the group that studied had a gap test. that had a gap test, they performed somewhere in the middle. What does this tell us?
What it tells us is so important vis-a-vis neuroplasticity, vis-a-vis best learning strategies. This is something that, goodness, I wish I had learned when I was in graduate school, when I was an undergraduate, when I was in high school and elementary school. Goodness, even when I was in kindergarten, I wish I'd learned this. Test yourself on the material that you were just exposed to very soon after your first exposure to it, because that offsets the natural forgetting of new material that the brain is exposed to.
This is absolutely the hallmark of all the impressive data about testing as a tool for learning. Testing oneself or your students, or being tested if you're the student by your teacher. as a tool, not just for evaluating performance, for knowing what you know and don't know, but for consolidating that information in your neural circuits. And when I say consolidating that information in your neural circuits, I realize it's a mouthful. What we know is that this business of putting the testing soon after exposure to new material is about offsetting the forgetting of that material.
So you might say, wait, if that's true, how come studying the material and then waiting and then taking two tests, right back to back where you're learning the material again during the test, that should be the best performing group. Ah, well, there seems to be something fundamentally different about first exposure to material versus testing yourself on that material. And we don't know exactly what that is. There's some interesting neural imaging data in humans that this has to do something with this notion of familiarity with material.
This is very simple. So this is easy to understand, even though it involves a little bit of memory neuroscience nomenclature. familiarity with something Recognizing it is not the same thing as having agility with that thing, of having mastery of that thing.
It's not the same thing as having mastery of the material, of having committed it to memory, okay? So when you read something over and over and over, you see it over and over, you hear it over and over, you think about it over and over, of course, you're reading it or you're hearing about it. And you think that you're learning the material, that your neural circuits are changing, but it's a pretty passive process, or even if it's a difficult chapter to read or a difficult passage of music.
The difference is when you're tested on material, something happens in your performance of or recalling of, if it's just cognitive or you're writing it down or you're told to play the music or do the motor movement, something happens in the error, the getting wrong of certain things that cues your nervous system to lock in the information. that you have right. And to remember what you have wrong so that you then correct it, which is far and away different than exposure and re-exposure and re-exposure. Okay, so it's a prerequisite to learning that you need to see the material for the first time.
You can't just start testing yourself on material that you've never been exposed to. I suppose you could, but you're going to get it, I would imagine, mostly wrong or all wrong. But this business of using testing very soon after first exposure to material, as a tool to study in order to offset forgetting is clearly tapping into this difference between familiarity with something for which we know certain brain areas are activated versus recollection, being able to take that material and bring it to memory.
bring it to your focused attention and use that material. I realize this is a bit abstract and some of this is still being parsed. If you're interested in the neuroscience of familiarity with something versus your ability to actually recall something and have mastery of that material, there's a really nice review that I provide a link to in the show note caption.
It's published in the journal Hippocampus. I always chuckle at. The fact that there's a journal that named after a brain structure, after all, as far as I know, there isn't a journal called retina or amygdala.
And I have a brief anecdote from graduate school whereby I learned that there was this journal, Hippocampus, and I was at a graduate, it was my first graduate student gathering in graduate school, and the guy who hosted it. Turns out it's a luminary in the field of learning and memory. And I was saying, you know, this is ridiculous.
Like there's a journal called Hippocampus. Here I am, first year graduate student. He goes, yeah, there is.
And I said, yeah, that's so silly. Like who are the idiots that name a journal? after a brain structure. Turns out there's also a journal called Cerebral Cortex and there's probably one about spinal cord. So it turns out I was the idiot saying this.
And the guy I was talking to, who of course was the host of the party said, yeah, actually that's my journal. I founded the journal Hippocampus. So you can look them up. So at this point, you're going to take a test and it's a super easy test.
I realize we're a bit into the material and we're all probably fatiguing a little bit. Marveling, I hope, at what an incredible tool testing and- in particular self-testing soon after being exposed to new material is, and the question is this, and by the way, this is an open-ended question. You're not supposed to know the answer because I haven't told you the answer yet, but I want you to think about this.
If one looks at the majority of data in this whole field of testing as a studying tool, how much improvement do you think you get from testing yourself once on new material? Do you think it's a, you know, 10% improvement, a 20% improvement? So here I'm just comparing to testing yourself once on material that you were just exposed to for the first time versus not testing yourself at all, okay?
How much do you think you improve? The answer is about 50%, five, zero. And I can say that on the basis of the fact that In studies of musical learning, of mathematical learning, of language learning, of motor learning, when subjects are exposed to new material and then tested at some period of time later, the percentage of information they get right or that they are able to perform something correctly. diminishes over time, especially because they're not doing any practice and no testing in the intervening time. This was built into these experiments.
And then you simply ask how much of the material was forgotten? if they just were exposed to the material. So in the case of say music learning, this would be, you know, your teacher sits down next to you and shows you the scales on the piano, but then you're not practicing them in between versus, or perhaps another example would be somebody gives you a lecture about a particular phase in history and then you're not being exposed to the material again and you're not self-testing versus if you just take one test, even a self-directed test of the material immediately after. Irrespective of how well you perform, you have the amount of forgetting, okay?
I want you to think about self-testing in this way because we're thinking about optimal studying strategies. You have the... amount of forgetting that would normally occur. This is oh so important.
In fact, I don't even know that most neuroscientists think about learning and neuroplasticity this way. Most everybody, including neuroscientists, are taught, were taught, continue to be taught that you're exposed to new material, you focus, okay, then during sleep, there's remodeling of the connections. All that's true.
But we really need to think about how most information that comes into our nervous system each day is forgotten. Most of it is completely discarded. There are some rare clinical deficits where people remember everything.
And I'll tell you, these people really struggle in life. They do not do well in work, in relationships. They remember every little detail of everything and it is incredibly disruptive to their quality of life.
It's nothing you want. You want to have a great memory for the right things. So when you self-test material, you have the amount of forgetting that occurs.
compared to if you're just exposed to the material. I want you to keep that fact in mind because that fact is the one that really hit me upside the head and made me realize, goodness gracious, how I wish that I'd self-tested myself on material that I wanted to remember over time. rather than reading it over and over.
I had this elaborate process for studying that I use all through college and graduate school. And it worked pretty well for me where I'd read and highlight, then I'd write out my notes. Then I would write little paragraphs about that stuff.
Now, some of that probably mimicked self-testing. Indeed, it had to have. And then of course I would take the quizzes and I would go to office hours.
You know, once I got serious about school, I got really serious about school. And of course I still forget things. I've made errors on this podcast before, in part from going too fast or making a joke that people didn't perceive as a joke. So the whole story there, but in any case, of course I make errors.
Of course, I've forgotten certain things and sometimes I misspeak. I always strive to get things accurately. We correct things in the show note captions. If they're called out to us, we're now using AI to review the podcast and adjust anywhere using insertions or actually replacing those words if we need to and so on and so forth.
But yes, we all forget things. We all make errors, but... If I had just known that testing myself on material while walking out of class or soon after getting home or later that evening or the next day would allow me to perform so much better on an exam, a midterm or a final exam, and of course I still would have studied because I was committed and you should still study as much as you feel is necessary to get mastery of the material for you. However, if I had known that testing oneself or being tested soon after exposure to material would have the amount of forgetting even out to a year later, I definitely would have saved myself a lot of time.
Let's talk about some specifics of ways that you can self-test or if you're a teacher or if you have good dialogue with your teacher and they are open-minded, perhaps they are open to hearing about what are the best forms of testing oneself as a tool for learning. The best tests are open-ended, short answer, Very minimal prompt tests. Not unlike the type that we've taken today during this podcast. As compared to multiple choice tests. Multiple choice questions allow for familiarity of names, of facts, you know, it's going to be A, B, C, D, and sometimes E is, you know, A and C, and so on and so forth.
And within each of those A, B, C, D, E answers, and you're looking for the right answer, you're looking for the familiarity, the recognition of something. Yes, this, not. Okay, that's the best answer you circle C, okay? This kind of thing.
As opposed to an open-ended question where you have to write out your answer, you have to recall the information, right? It requires a much greater degree of mastery of the information than does familiarity or recognition of the material. So the best tests as study tools are going to be open-ended. Short answer questions or even long answer questions.
Now there's one exception to this, which are multiple choice tests that include tricks. Okay, if you've ever taken the GRE, the Graduate School Entrance Exam, or the LSAT or the MCAT, there are some questions in there that are very straightforward, but in those standardized tests, they tend to include some quote unquote trick questions in which those questions don't allow you to just recognize the correct answer and distinguish it from the other. incorrect answers, but rather they have answers in there that on first blush look like the right answer and people have a tendency to circle those and move on or to select those and move on. But if you think about the material a little more deeply, turns out those quote unquote obvious answers are actually the incorrect answers.
So there are versions of multiple choice tests where it requires a... a greater degree of mastery of the material where simple familiarity won't serve you and you actually have to be able to recall the different components of information leading into that. But those are a bit more rare, certainly in the context of other kinds of learning, like musical learning.
Although I suppose for music theory, that could be relevant. But when I say music learning, I'm just kind of defaulting to the idea of the mechanics of musical learning. But of course there's music theory, et cetera.
So what I'm effectively saying is the ultimate exam The final exam, the midterm exam, the exam that's administered to you, rarely do you have control over the format of that exam. Sometimes it's mixed format, but the different ways in which you self-test as a form of studying are really key. And ideally you would make these open-ended. In other words, you would not simply rely on multiple choice.
You would rely on a form of self-testing or that you give your students or that your teacher gives you that requires you to think about the material with some degree of. with some degree of effort. And of course you're going to get certain things wrong. Now I would hope that if testing is being used as a learning tool, as opposed to just for evaluation, but here we're talking about using testing as a learning tool, that it wouldn't impact, at least not at that moment, your final performance in the course or whatever it is. Rather it is testing for sake of learning.
Now we know from the literature that students don't like pop quizzes. I gave you a few today and forgive me. They don't like pop quizzes. And we know this in the form of the reduction in teaching evaluation scores, okay? Having received teaching evaluation scores of different, let's say values over the years and I always take the feedback seriously.
One salient comment that just leapt into my mind was the fact that I ended up mentioning my bulldog Costello too often in class. So here I'm mentioning him again, just to get back at that one student that said I mentioned him too much. I mentioned him as much as I want. The point here is that when students evaluate their teachers they tend to punish their teachers for pop quizzes.
Does that mean pop quizzes aren't effective? No, but you know what's more effective? Telling students at the outset of class or telling yourself at the outset of any kind of learning expedition, because this isn't just about the classroom, that you're going to take a bunch of exams, that you're going to use testing or quizzes, whatever you want to call them, as a form of teaching and learning, and that you can expect five tests or five quizzes.
during the course of being presented the material, or that you are going to test yourself every day after the material. Now, sometimes you have to go from one class to the next class. There isn't an opportunity to test yourself, but guess what's not going to be helpful? Walking out of class and getting immediately onto your phone. We know that that probably inhibits your ability to remember the material because it's going to enhance forgetting because you do have this key opportunity right after being exposed to new material to help offset the forgetting.
by testing yourself on that material as soon as possible after being exposed to it. So again, even though I did not attend school in an era where we had smartphones and texting, I recall walking out of class and just walking out of class and going on my bicycle. But of course there were people to talk to, there were other things to attend to. If you're really serious about learning material, take a few seconds, maybe even a few minutes after being exposed to that material and think about that material.
Test yourself on it. And if you find that you don't know the material, you're confused by it or overwhelmed by it, great. You just accomplished the first step in cuing your nervous system to the fact that it needs to learn that material and you've created an opportunity for enhanced neuroplasticity, which is really what all of this stuff about testing as a form of studying is about. You're going to test yourself so that you figure out what you don't know. so that you then look up that material, test yourself on it again, so that ultimately you forget very little of it, if any.
Now, there are other components to learning and neuroplasticity that I've talked about on previous podcasts that are just too interesting not to mention, but I'm just going to mention them in brief, things like gap effects. Gap effects are oh so cool, and they've been demonstrated for lots of different forms of learning. Gap effects are what I just did, which is to take periodic pauses.
In the learning of material, as short as five to 10 seconds, but even as long as 30 seconds, during which, guess what? Your hippocampus, the neurons in your hippocampus, repeat information that you've been exposed to for the first time at a rate 20 to 30 times faster than typical, just as it does during rapid eye movement sleep. So if you are a teacher and or if you are a learner, periodically throughout, an episode, a class, or whatever of trying to learn new motor skills, or music skills, or whatever kind of learning.
Pause and let your hippocampus generate more repetitions of that material than it would otherwise if you just tried to barrel through. So I realize as we've gone through today's discussion that words like test and quiz, evaluation, offsetting, forgetting, all of that stuff can spike people's cortisol. It can give us flashbacks to uncomfortable classroom experiences related to being called on, cold called for the answer, a vicious trick that instructors play.
Keep in mind that testing as a form of studying, whether or not self-directed or given to you by a teacher is not for sake of evaluation at the level of, okay, you get an exam at the end of a lecture and then you do your best to answer those questions and then you turn it in and it impacts your grade. No, this is about being told or revealing to yourself how much you know and don't know. And then of course being told the correct answers so that you can compare your answers to the correct answers and doing this frequently and ideally very soon after being exposed to the material.
That's one of the key things that I keep coming back to again and again here because it's something that frankly was not done while I was in school for whatever reason. And I think that's largely because when people hear the word testing, they think of evaluation. And if anything, at least in the United States, over the last...
but in particular over the last 15 years, there's been this tendency to shift away from formal evaluation. I personally believe that one can learn in many different styles and many different contexts. I, of course, as a university professor, believe that for certain topics, in particular science and medicine and health, but other topics as well, of course, that formal rigorous coursework is by far the best way to learn information for me.
But that regardless of whether or not you're learning just from YouTube, or you're learning from podcasts, or you're learning from books, or you're learning from the school of life, as it were, from experience, that testing as a form of studying is absolutely key. And gosh, there's such a beautiful body of research. In fact, I'll link to several studies, including a review entitled Testing Enhances Learning, a review of the literature, as well as a beautiful article, Test Enhanced Learning. which gets into this.
And there's a wonderful book about this that I'll also provide a link to in the show note captions, all of course authored by researchers who have worked squarely in this field and compare the data on testing as a studying tool to other forms of studying and learning. So it's a really impressive literature that I do believe we all should have known about. And that's why I'm passing it on to you now.
Now, before we wrap up, I want to make sure that I emphasize some of the other key components to studying and learning that... Have nothing to do with testing as a studying tool. And those are the role of emotion, the role of story, and the role of what's called interleaving. Now, in terms of emotion, I think we all inherently understand that more emotionally-laden experiences are remembered more durably.
We tend not to forget them. In fact, this is the basis of things like PTSD. Post-traumatic stress disorder. It is the reality that one trial learning that is exposure to something and never forgetting it occurs very readily when the thing that we're exposed to is negative or has a very heavy negative emotional salience. So it could be something we read or something we see.
Sometimes it's something that happens to us. You know, I don't like the idea of that, but this is true. Your nervous system is wired such Neuroplasticity is such that stressful experiences, because they deploy such massive amounts of adrenaline, epinephrine, as well as other neuromodulators, allow very quickly for the milieu, the environment of the neural circuits that led up to that experience to strengthen their connections with one trial, so-called one trial learning.
This is why, sadly, although at the same time from an- adaptive perspective, we say, fortunately, if you were to step outside today and God forbid, see somebody get hit by a car, you would remember that. Chances are you would remember that forever. Now that does not mean that the emotional components of that memory are necessarily going to stay within you.
There are tools for the treatment of PTSD, such as the different ones that come to mind or, you know, systematic exposure therapy where you're. re-exposed to that idea or memory, sometimes even circumstance, with, of course, the support of a trained professional, typically a psychiatrist or psychologist. And the emotional load of that experience is gradually uncoupled from your memory of the experience. There's things like EMDR, there are pharmacologic approaches.
Some of these are combined with the sorts of things I've described. I've done entire episodes about stress and PTSD. Again, you can find those at hubermanlab.com by putting stress PTSD into the search function.
However, we know that it is the same neuromodulators, mainly epinephrine and norepinephrine deployed at massive amounts in those moments where something very stressful happens that allows the neural circuits that led up to the circumstance, as well as the neural circuits that encode that visual scene and scenes like it or sounds like it to be locked in and linked to the stress response. Now, what this is really all saying is that negative stuff is remembered Typically the first time and every time and very durably over time. As compared to positive experiences, which as far as peak experiences go, right?
Birth of your first child, a wedding, a wonderful professional or personal experience, those two can be one trial learning and memory. But most things that we are exposed to are not at those extremes, either negative or positive. However, we know that any kind of story, any kind of emotional emphasis on material, either in the delivery of that material, but certainly in the way that that material is perceived by you, like getting really excited about something you want to learn or thinking something's really awful is likely to be more readily and stably. committed to your memory.
And that's because of these neuromodulators like epinephrine and norepinephrine, but other neuromodulators as well that wire those experiences into your neural circuits. Again, these neuromodulators, epinephrine, norepinephrine, we also hear about acetylcholine, dopamine, et cetera, they can operate at low levels and sort of background levels. They can create...
Subtle fluctuations in mood, focus, and attention, or they can create massive shifts in mood, focus, and attention depending on their levels, their timing, and much, much more. Point here is that if you're a teacher and or if you are a learner, paying attention to your internal state as you're trying to learn is very key. We've all had that teacher, that lecturer that just kind of drones things out and monotone. If you need to learn the material coming out of a source like that, person or otherwise, You're going to have to ramp up your level of internal attention consciously in order to bring about some emotional salience, some intensity to the way it's perceived. And you can do that just through your own thinking, as opposed to the situation where you have a super dynamic teacher who's telling you things with wide eyes and perhaps even cracking jokes.
By the way, the teachers that crack jokes get lower teacher evaluations than those that don't crack jokes or swear. Did you know that? Teachers that crack jokes and swear.
They're perceived as more likable, but they get lower overall evaluations typically. They're seen as less professional and therefore less good teachers by their students. So I try not to make too many jokes or swear in my lectures.
The point being that we all have those really wonderful dynamic teachers. Yes, it's much easier to learn and remember that material. You still need to test yourself on it, but it's much easier to learn that material for the very reasons I stated before.
It's a lesser example of more deployment of the neuromodulators in you, the learner that is exposed to that material, okay? So emotion matters. So much so that in a beautiful review about learning and memory from the great James McGaugh, one of the luminaries in modern neuroscience and psychology of memory, he talked about a medieval practice. This is pretty wild. Whereby...
People and kids, kids are people of course, but adults and kids were taught information and then thrown, literally thrown into cold water. Why? To deploy adrenaline and consolidate memory of the material they were exposed to. Now, I know we've covered deliberate cold exposure on this podcast before.
No, I'm not saying you need to do a cold plunge after being exposed to new material, but guess what? They were doing that many hundreds of years ago and it makes sense logically based on all our understanding of the neurobiology underlying things like PTSD, underlying emotion-laden memory formation and consolidation and our ability to remember things that were emotionally laden much better than things that were less emotionally laden. So if you want to take a cold shower after learning some material or even better testing yourself mentally on that material while in a cold shower or cold plunge, you certainly can. Just don't stay in there too long.
Use best practices. If you want to know what those best practices are for deliberate cold exposure, you can check out our deliberate cold exposure newsletter at hubermanlab.com. It's completely zero cost.
You don't even need to sign up. You simply go to newsletter in the menu tab and you can find that PDF. And now, because you are becoming proficient in an understanding of neuroplasticity and learning and testing and neuromodulators like epinephrine, yes, drinking caffeine will increase your levels of epinephrine.
Not strikingly so, but. enough that it probably helps you learn things a little bit better. Should you drink the coffee after?
Listen, that's getting a little bit too down in the details. The most important components to learning are that you be alert so that you can attend, so you can pay attention to the material you're trying to learn and then testing yourself later. And of course.
which is getting sufficient amounts of great sleep each night, and I highly recommend doing NSDR. I mentioned gap effects before. Those are very, very cool.
I just used another one now. And the final tool for studying that I believe is not discussed enough and is a bit counterintuitive, so it's a fun one to just mention, and that perhaps you can explore in your own studying and learning adventures, is interleaving of information. This one's kind of wild, actually.
Turns out, That if your instructor or you takes information about something that they're trying to teach you or you're trying to learn, maybe it's piano, maybe it's neuroscience, maybe it's how to learn better. And every once in a while throws in a little anecdote about something, let's just say, or mention something about the Olympics or incorporate something that seems pseudo random because it's not actually related to the material you're trying to learn. Turns out that that acts not as a gap in the same sense that gap affects, which are times in which you do nothing in order to get more repetitions of the material that you just heard in your hippocampus, but rather those breaks of interleaving information, not just getting a steady barrage, like drinking from a fire hose of new information from start to finish, turn out to enhance overall learning ability. Probably, we think, at a mechanistic level, because... the neural circuits are able to generate more repetition, similar to gap effects, but actually in a very interesting way also because by injecting other information that seems totally unrelated, random or pseudo random, it allows the brain areas that are responsible for encoding information.
to take whatever new information you're learning and to incorporate it with existing knowledge or even distantly related knowledge. So does this mean that you should learn math and history in the same lecture? Well, I think that might be a bit overwhelming, kind of like drinking from two fire hoses. Here we're talking about interleaving challenging information that's new to you with little anecdotes, little bits of information that perhaps are new to you, but don't require a lot of challenge.
which is of course why every once in a while, I throw in a little anecdote about my bulldog or learning neuroanatomy or something of that sort. It's not just to provide a break, it's to provide examples that are related, but not central to the material that we've been talking about today, which is all about how to study and learn optimally. Okay, so I realize that many of you are not. Students any longer, although some of you are, but in many ways we are all students.
We are all constantly being exposed to all sorts of information out in the world. And goodness knows, thank goodness, we don't remember it all. But there is of course information that we would like to remember, that we would really like to consolidate in our memory and be able to have some mastery over. Earlier I said I would distinguish between unskilled, skilled, mastery, and virtuosity, and I'll do that now.
Unskilled of course means that we have limited understanding, let alone ability to use information. Skilled typically means we know and can recognize and use information in basic ways or even advanced ways. Mastery typically means that we have, you know, close to the full depth of knowledge in a given area and that we can use it pretty flexibly. And virtuosity, at least my definition of virtuosity is where we actually have such mastery of material that we can use it in ways that we still don't even know or know.
how we can use. Meaning that we can inject elements or we even invite elements of uncertainty and kind of spontaneity into the use of that material. Here, I'm thinking of great musicians, I'm thinking of great athletes, where they know all the plays, they know all the moves, it's all scripted into their nervous system and they can deploy those at any time, so they have real mastery. But in order to display their incredible abilities, their virtuosity, they actively invite in the X factor, the uncertainty.
such that sometimes they find themselves playing their instrument or singing or performing athletically or mathematically or what have you in ways that even surprise. And that of course is a lot to expect of ourselves. I think most of us would be content to have skill and mastery of the things that we care about.
And should we achieve virtuosity, then wonderful. But one of the main points of today's discussion was to arm you with an understanding of neuroplasticity. In the context of studying and learning, to really understand that so much of learning stably and consolidating information over time is to offset the forgetting process, and that testing is not just a tool for evaluating our knowledge, but rather a tool for evaluating and reinforcing and building our knowledge.
Put differently, that testing is an excellent tool, if not the best tool for studying. And I think that's an important reframe that others have brought about and that I really want to. highlight, underline, and boldface during today's discussion.
It's one that I certainly wish I had applied more in my educational trajectory, and it's one that I plan to deploy further in my seeking out of new knowledge. in terms of the podcast and neuroscience, but in other areas of my life as well, because from the existing literature and hopefully from the way it was presented to you today, you probably realize that it is near infinite, if not infinite, that we can apply testing as a tool for studying, self-testing, testing of others, using testing as a way to really probe what we know and don't know and to really offset that forgetting process. And in that sense, it is really nicely aligned with what we know about neuroplasticity, and it's also something that we can use freely and that you can use covertly, that you can apply in your own seeking out of knowledge and new skills of all kinds, classroom or otherwise.
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For those of you that haven't heard, I have a new book coming out. It's my very first book. It's entitled Protocols, an Operating Manual for the Human Body.
This is a book that I've been working on for more than five years and that's based on more than 30 years. of research and experience. And it covers protocols for everything from sleep to exercise, to stress control, protocols related to focus and motivation. And of course, I provide the scientific substantiation for the protocols that are included. The book is now available by presale at protocolsbook.com.
There you can find links to various vendors. You can pick the one that you like best. Again, the book is called Protocols, an operating manual for the human body. If you're not already following me on social media, I'm Huberman Lab on all social media platforms.
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And we have protocols related to neuroplasticity and learning. Again, you can find all that at completely zero cost by going to hubermanlab.com, go to the menu tab in the right corner, scroll down to newsletter. you put in your email, and we do not share your email with anybody. Thank you once again for joining me for today's discussion, all about how to study and learn. And last, but certainly not least, thank you for your interest in science.