Science-Based Mental Training & Visualization for Improved Learning

Andrew Huberman 0:00 (music plays) 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 mental training and visualization. Mental training and visualization is a fascinating process that has been shown over and over again in, now, hundreds of studies to improve our ability to learn anything. When I say anything, I mean the ability to learn music, the ability to learn and perform mathematics, the ability to learn and perform motor skills in sport, in dance, across essentially all domains. The other incredible thing about mental training and visualization is that a- as y- you'll soon see when you go into the literature, that is the scientific studies on mental training and visualization, you quickly realize that it does not take a lot of mental training and visualization in order to get better at anything. However, that mental training and visualization has to be performed in a very specific way, and today, we will discuss exactly how to do mental training and visualization in the specific ways that allow it to complement the actual performance of a motor or cognitive skill to allow you to learn more quickly and to consolidate, that is to keep that information in mind and body so that you can perform those cognitive tasks, music tasks, motor tasks, et cetera, for long periods of time without ever forgetting how to do them. All of mental training and visualization relies on what I consider really the holy grail of our brain and nervous system, and that's neuroplasticity. Neuroplasticity is our nervous system, which of course includes the brain, the spinal cord, and all the connections between the brain and spinal cord and the organs and tissues of the body and then all the neural connections back from the organs and tissues of the body to the brain and spinal cord, so the whole thing in both directions, has the ability to change in response to experience in ways that are adaptive, that is that allows us to do things that we could not do before. And by doing those things or by being able to perform those mental operations, we can do better in the world that we live in. We can perform new tasks, we can think new thoughts, we can come up with novel solutions to preexisting problems that before really vexed us and that we couldn't overcome. All of that is considered neuroplasticity. So today, what I'm going to cover is a brief summary of what neuroplasticity is, that is how it occurs in the brain and body. This is extremely important to understand if you're going to use mental training and visualization. Then I'm going to talk about what happens in our brain and body when we do mental visualization in a dedicated way. Many people have heard perhaps that when you imagine something happening, that your brain doesn't know the difference between that imagination of the thing happening and the real thing happening. Turns out that is not true. It is simply not true. However, there is somewhat of an equivalence between a real experience and an imagined experience, and we'll talk about the difference between those and how that can be leveraged in order to get the most out of mental training and visualization. Then I will cover exactly which types of mental training and visualization work best across all domains, meaning for music learning, mathematics, solving puzzles, motor learning, sports performance, et cetera, et cetera, to really allow you a template in which you can plug in or designate what you're going to do each day for a brief period of time in order to accelerate your learning in whatever you choose. And then I'm going to go into a bit of what happens in the brains of different types of people. Uh, these different types of people that I'm referring to are people who have more or less of a natural ability to imagine things and visualize them, because it turns out that we vary tremendously from one individual to the next in terms of our ability to mentally visualize and imagine things and our ability to get better at that over time. And the good news is anyone can get better at mental training and visualization in ways that can serve them well. I'll also briefly touch on the fact that certain people, in particular, people on the autism spectrum, as well as people with synesthesias, which is the combining of different perceptual experiences, so you may be one of these people or you may have heard of people that, for instance, when they think of a number, they also just naturally, spontaneously think of a color and vice versa. We'll talk about how that relates to mental imagery and visualization and the creative process and problem-solving in general. And then finally, what I'll do is I'll recap mental training and visualization from the standpoint of how best to apply mental training and visualization according to specific challenges, things like challenges with public speaking or challenges with sports performance or challenges with test-taking performance, challenges with essentially anything that will allow you to build specific mental training and visualization practices that are brief, that are supported by neuroscience studies, and that are highly effective.

Andrew Huberman 4:46 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 LMNT. LMNT is an electrolyte drink that has everything you need, meaning sodium, magnesium, and potassium, but nothing that you don't, meaning no sugar. And it has the sodium, magnesium, and potassium in the ideal ratios for hydrating and providing electrolytes to the cells and tissues of your body. So I use LMNT in my water when I wake up. I like to hydrate right away, so I'll have an LMNT packet in about 16 to 32 ounces of water when I wake up. I tend to do the same while I exercise, which I typically do in the morning, sometimes in the afternoon, and I'll drink another one throughout the day. The great thing about LMNT is it also tastes terrific.I particularly like the watermelon flavor, but frankly I like all the flavors. Just mix into, again, about 16 to 32 ounces of water. If you'd like to try LMNT, you can go to DrinkLMNT, L-M-N-T, .com/huberman to claim a free LMNT sample pack with your purchase. Again, that's Drink LMNT, L-M-N-T,.com/huberman. Today's episode is also brought to us by Maui Nui Venison, which I can confidently say is the most nutrient dense and delicious red meat available. Maui Nui spent nearly a decade building a USDA certified wild harvesting system to help balance deer populations on the island of Maui. The solution they built is extremely powerful because it turns the proliferation of an invasive species into a wide range of nutrient dense products, from butcher cuts, so venison steaks, and ground venison, et cetera, to organ meats, bone broth, and jerky. I really love all of their products, so I love the venison steaks and the ground venison, and their bone broth is fantastic. It has an unmatched 25 grams of protein per 100 calories. So it's very high density, high quality protein per calorie. So if you'd like to try Maui Nui Venison, go to mauinuivenison.com/huberman to get 20% off your first order. Again, that's mauinuivenison.com/huberman to get 20% off your first order. Today's episode is also brought to us by Eight Sleep. Eight Sleep makes smart mattress covers with cooling, heating, and sleep tracking capacity. I've talked many times before on this podcast about the fact that sleep is the foundation of mental health, physical health, and performance. And one of the key features to getting a good night sleep is making sure that you get the temperature of the environment you sleep in right. That's because in order to fall asleep and stay deeply asleep throughout the night, your core body temperature needs to drop by about one to three degrees. Conversely, in order to wake up in the morning feeling refreshed and ready to go, your core body temperature needs to go up by about one to three degrees. Now of course, you can adjust the temperature of the room that you sleep in, and I do hope that people are doing that, but adjusting the temperature of your mattress and your direct sleeping environment is also key. And with Eight Sleep it makes it very easy to program the temperature of that mattress and sleep environment, not just throughout the night but for specific phases of the night. I started sleeping on an Eight Sleep mattress cover well over a year ago, and it's the best sleep that I've ever had. If you'd like to try Eight Sleep, you can go to eightsleep.com/huberman and check out the Pod Pro cover and save $150 at checkout. Eight Sleep currently ships in the USA, Canada, UK, select countries in the EU, and Australia. Again, that's eightsleep.com/huberman to save $150 at checkout. Let's

Andrew Huberman 8:04 talk about mental training and visualization. Now perhaps surprisingly, mental training and visualization has been studied since the late 1800s. There's actually a paper published in 1880 by Galton called The Statistics of Mental Imagery. So long ago, people were quantifying and trying to understand how is it that people come up with mental images and how they can apply that to learning things more quickly and more stably over time. Now, as I mentioned earlier, mental training and visualization relies on a process that we call neuroplasticity. Neuroplasticity is a term that many people have heard, and it encompasses many different things. So broadly speaking, neuroplasticity includes developmental plasticity, which is the sort of plasticity that occurs between about birth and age 25, and that can be summarized very easily as passive plasticity. In other words, the sorts of changes that happen in one's nervous system simply by engaging in the world and experiencing life as a child, as a young adult, as an adolescent, and as a 22, 23, 24-year-old, et cetera. Now of course, of course, of course, it is not the case that on your 25th birthday you close out passive developmental plasticity and start engaging in the other type of neuroplasticity, which is adult neuroplasticity. It's a gradual tapering off of developmental plasticity that occurs between age zero and 25, and for some people might occur somewhere around 26, for other people around 23. When we say 25, we're really just talking about the average age in which passive plasticity tapers off. However, starting fairly early in adolescence and extending all the way out into one's 80s or 90s or 100s, should one live that long, is the other form of neuroplasticity, which is adult neuroplasticity. Adult neuroplasticity is very different than developmental plasticity because it is the sort of plasticity that one can direct towards one's own specific desired learning. So if we wanted to get a little bit technical here for sake of clarity, not for sake of confusion, we would say adult plasticity is really about self-directed adaptive plasticity. And the reason we call it that as opposed to something else, or simply adult plasticity, is that there are many different forms of neuroplasticity. There is, for instance, maladaptive neuroplasticity that occurs if one gets a really hard head hit and concussion. There will be changes to the brain and nervous system, but those changes to the brain and nervous system do not allow it to perform better. In fact, it often impairs the brain and nervous system's ability to function and therefore is maladaptive. So I don't want to get overly wordy with a number of different terms here, but I do think it's important to understand that we have developmental plasticity, again in which the brain and nervous system changes simply in response to experiencing specific things, for better or worse, and there's adult self-directed adaptive plasticity in which one can direct specific changes in terms of learning things cognitively or learning things in terms of motor function, so sport, dance, et cetera, or a combination of the two. Now just to really clarify what I mean by developmental versus self-directed adaptive plasticity, I mentioned that self-directed adaptive plasticity actually can start in adolescence, right, even though there's ongoing developmental plasticity. I mean, let's be really direct. The brain of a 14-year-old is very different than the brain of that same individual when that person is 21, because there's ongoing developmental plasticity. However, starting at about adolescence we can all start to decide what it is that we want to learn and engage in self-directed adaptive plasticity.Now,

Andrew Huberman 11:42 the way to engage self-directed adaptive plasticity, regardless of whether or not you're a 13-year-old, 14-year-old, or you're a 90-year-old, or anywhere in between, is that it requires two things. The first thing it requires is focused, dedicated attention to the thing that you're trying to learn. That's the first step, and that actually triggers a number of different chemical and electrical processes in the brain that are often associated with agitation and frustration. Believe it or not, the agitation and frustration is a reflection of the release of specific chemicals, in particular norepinephrine and epinephrine, also called noradrenaline and adrenaline, in the brain and body, that creates this discomfort and this heightened level of alertness and attention that many of us don't like and tend to back away from. But it is exactly that chemical, or I should say neurochemical milieu, which signals to the neurons, the nerve cells in the brain and elsewhere in the body, that something needs to change. Because if you think about it, if you can do something perfectly, or if you try and do something and it doesn't cause any neurochemical change in your brain and body, well then there's no reason for your brain and its connections with the body to change in any particular way. Okay? So you need focused, dedicated attention to the thing that you're trying to learn. It's often accompanied by agitation, frustration, et cetera. So that's perfectly normal. In fact, that's a signal that things are going right, meaning they're headed towards learning. But there's a second component that's really required for self-directed adaptive plasticity, and that's periods of deep rest, in particular a good night sleep, in particular on the night that follows that focused attention to the thing you're trying to learn. There are now hundreds of studies in both animal models and in humans showing that it is really during sleep and other states of deep relaxation, things like meditation and non-sleep deep rest, which I've talked about before on this podcast, but really during our main night of sleep, that the rewiring of neural connections, that is, the actual neuroplasticity, takes place. So the verb neuroplasticity, the rearrangement of connections between neurons, really occurs during sleep, in particular on the first night following an attempt to learn something through this focused attention. Now, developmental plasticity, which is passive, also requires good sleep. It's slightly different, or frankly it's a lot different, in terms of the underlying mechanisms than self-directed adaptive plasticity. But because today we're mainly talking about how to learn faster through mental training and visualization, and that really maps more closely onto self-directed adaptive plasticity, I just really want to emphasize this two-step process. There has to be focused, dedicated attention, and then there needs to be sleep, uh, and in particular sleep on the first night following that training. Now, should you have the unfortunate experience of getting woken up in the middle of the night following trying to learn something, or should you simply not be able to sleep for whatever reason on the night following a bout of learning or an attempt to learn, do not despair, because it turns out that there are what are called second and third night effects also. Once you sleep, you will learn. Those neuroplastic events, the reordering of connections that we call synapses and the r- changes that occur in neural circuits that reflects what we call

Andrew Huberman 14:49 self-directed adaptive plasticity, that still will occur. But ideally, you got a great night's sleep on the first night following trying to learn, and the second night, and the third, and so on and so on. Now, there are a few other things that are critical to understand about self-directed adaptive plasticity that will become especially important when thinking about protocols for developing the ideal mental training and visualization process for you, and that is that there are different forms of plasticity that occur between neurons, although the two main forms are what are called long-term potentiation and long-term depression. I just wanna cue up right now that the word depression is a very loaded word, because the moment people hear the word depression, they think, "Oh, no, that's bad." But in the case of neuroplasticity, long-term depression is simply a change in the connections between neurons and the excitability between neurons that in many ways can be excellent for learning things, in particular motor skills. And we'll get into this in more detail in a little bit, but it turns out that a lot of our ability to get better at some sort of motor skill involves this thing that we call long-term depression. And that's because much of what is happening when we learn a new motor skill is that we are depressing or suppressing specific actions in order to generate a very specific coordinated action. Some of the best examples of long-term depression can actually be borrowed from developmental plasticity. So for instance, if you've ever sat across from an infant who is trying to eat their meal, so imagine a one-and-a-half-year-old or a two-year-old trying to eat some noodles or some soup or any kind of baby-suitable food with a spoon, and they're holding the spoon or they're trying to hold the spoon. What you'll notice is that their motor movements are terribly uncoordinated. They often will take that spoon to their cheek or to their eye or to their head. We've all seen these very amusing photos of babies with bowls of food on their head or with food all over their face or just everywhere. It appears that they're basically getting the food everywhere except where it's supposed to go, which is in their mouth. And that's because their motor movements are not very well coordinated at that age, and they're not very well coordinated not because they lack sufficient numbers of neural connections, synapses between neurons, but rather because they have too many connections between too many different neurons. The neural circuits that control very dedicated, coordinated movement are not there yet. Instead, too many neurons are connected to too many other neurons, and so they can't generate the precise movements that are required in order to get that spoon to their mouth. Now, over time, they get better at moving the utensil to their mouth such that hopefully by about f- age five or six, they are eating, you know, in a relatively cleaner way. And hopefully by the time they're 10 or 11 or 12, they're getting the food into their mouth and not all over their face. Uh, people learn this to varying degrees. All you have to do is go to a restaurant and watch how people eat, um, and you will see a vast variation in people's coordinated movements with utensils. But in general, there's a theme. The younger the person-... the more uncoordinated their movement of utensils. And as they get older, they're more coordinated. Now, of course, in people that are very old, they have challenges moving objects and their limbs in very smooth ways, and that has to do with a topic that we'll get into when we talk about age-related cognitive decline and motor-related dementias. But for the sake of today's discussion, if you just want to think about what happens with long-term depression and the development of a motor skill, both as a baby, as an adolescent, and as an adult when you're trying to learn a new motor skill, is that you are eliminating incorrect movements. And when you are eliminating incorrect movements to arrive at only the correct movements in a very reflexive and repeated way, so think your golf swing, your tennis serve, think serving a volleyball, think a child learning to crawl and then walk, think a child learning to eat with utensils in the example I gave before, what's happening in all of those cases is that, yes, certain connections in the brain are being strengthened or what we call potentiated. They are undergoing long-term potentiation, the so-called, quote unquote, "fire together, wire together" mantra that was popularized by the great neurobiologist, Dr. Carla Shatz, my colleague at Stanford. But in addition to that long-term depression, the quieting or the silencing of specific synapses, that is connections between neurons, is absolutely critical for motor skill learning. So we have LTP, long-term potentiation, and LTD, long-term depression, is every bit as important as LTP, long-term potentiation, for getting better at some sort of motor skill and indeed at getting better at some sort of cognitive skill. Now, as we hear this, this should be intuitive to all of us. If you look at somebody's attempt to learn a particular dance step or at somebody's attempt to do a tennis serve the first time, it's all over the place. Now, it's not perhaps all over the place in that they're doing a jumping jack while trying to serve the tennis ball, but they're generally arcing the racquet too widely on one trial and then they're arcing it too close to their body on the next trial. So if we were to draw a line over each one of those trials, we would see that there were lines everywhere over time. Whereas once they, quote unquote, "perfect" the tennis serve, it's going to be line drawn directly over line, draw- directly over line, meaning the arc of that tennis serve is going to be very restricted. And that, without question, has reflected the removal or the quieting of particular synapses, connections between neurons in the brain and body, to allow that very narrow coordinated and directed movement. The same is true for learning anything in the cognitive domain, meaning if you were to learn a language, it is not, of course, the case that you know every word in that language and then you simply remove certain words and arrive at the correct sentence structure that you're trying to achieve. But rather, you have to suppress your native language, or if you're a young child, you have to suppress the generation of just kind of random babbling sounds, turns out babbling isn't random at all, but the point is that you have to suppress the enunciation of particular sounds and direct the pronunciation of other sounds in order to generate that new language or your ability to speak at all. Okay? So we can really think about neuroplasticity as both a building up process in which you increase connections, so-called long-term potentiation, and a sculpting down or a removal of connections process that we're going to call long-term depression. Now, I have to acknowledge that, of course, there are other forms of neuroplasticity too. I know there are probably some aficionados listening to this who will be perhaps shouting back at, uh, whatever, uh, device my voice is coming out of, "Wait, what about spike-timing-dependent plasticity?" Or, "What about paired-pulse facilitation?" Yes, yes, and yes. There are multiple forms of communication between neurons that can strengthen those connections or weaken those connections. But for today's discussion, we just broadly want to think about long-term potentiation and long-term depression because it captures the two most important themes related to mental training and visualization, which is that when we perform a given cognitive or physical task in the real world, so we actually try the dance step or the tennis serve, or when we actually try a math problem or we try and learn some specific knowledge and write it down and remember it, that is engaging particular neurons, right? They're firing, they're releasing chemicals. But it is also actively suppressing the activity of other neurons. And we are always completely unaware of the ways in which our brain is suppressing certain activity. Okay? So today we have to keep in mind that where there is strengthening of connections, there is also weakening of connections, and when it comes to mental training and visualization, and here's the really key point, with mental training and visualization, you are capturing both processes, both the potentiation, that is the building up and strengthening of connections, and the weakening of the connections that are inappropriate for the thing you're trying to learn. And there are different aspects of mental training and visualization protocols that really harness the potentiation versus the depression aspect. And today we will cover mental training and visualization protocols that capture both the potentiation and the depression aspect of neuroplasticity and in that way serve as an augment, that is a complement to the actual real-world cognitive and physical training that you're doing, because I'll just give this away right now, turns out that mental training and visualization is not a replacement for real-world cognitive or motor behavior. Again, mental training and visualization cannot replace real-world execution of cognitive tasks or of motor tasks if you want to learn. However, mental training and visualization can and has been shown to be effective for greatly enhancing the speed at which you learn and the stability of that learning over

Andrew Huberman 23:42 time. Okay, so let's take a second and really think about what's happening in the brain and body when we do mental training or visualization. In fact, we can do a little experiment right now that is not unlike many of the classic experiments looking at what's happening in the brain and body through mental training and visualization, in which I just ask you to close your eyes and imagine a yellow cube. Okay? And next to that yellow cube is a red rose.... and perhaps I also ask you to float or fly up above the cube and the rose and look at them from the top, top-down. And then I tell you to fly back around and land behind those and look at them from the perspective of behind that yellow cube and that red rose. Okay? Now, what the data tell us is that most people will be able to do that. Most of you will be able to do that to some degree or another. Regardless of your attention span, whether or not you have ADHD or not, most of you will be able to do that to some degree or another. We also know from neuroimaging studies in which people are placed into a functional magnetic resonance imaging scanner that during this sort of visualization you just did, or that I described, that your visual cortex and associated areas, quote-unquote, "light up." They become very active in similar but not identical ways to how they would light up and be activated were you to actually look at a yellow cube and a red rose on a screen and perhaps fly above them, virtually of course, and land behind them, virtually of course. Or if you were to actually look at a yellow cl- cube and red rose in the real world, right in front of you on a table, then, you know, get up on your tippy-toes and look down at them from the top and then walk around the table and look at them from the other side. So, there is some degree of what we call perceptual equivalence between real world experiences, digital experiences, and imagined, meaning with our eyes closed, just in our mind's eye, experiences. This is true not just of vision and what we call the visual domain, but also the auditory domain. Okay? So for instance, I could play for you a short motif of a song. Let's just pick something that I think most people know. Goodness, I'm a terrible musician and even worse, um, singer. But let's just take the, the opening to AC/DC's Back in Black, right? I think I can do that one. It's like <singing . Okay, got it. That's the, the actual sound, although, uh, admittedly a dreadful version of, of the great AC/DC song, Back in Black. But now, I ask you to close your eyes, or you could keep them open and just imagine that <singing , okay? Or for instance, I place you in a quiet room. So, you close your eyes and I ask you to imagine the opening to AC/DC's Back in Black, but I ask you to pause it halfway through. What you would find again is that most people, somewhere between 90 and 95% of people, would be able to do all the sorts of things I described, right? Cube and rose, AC/DC Back in Black. Even a somatosensory task, I imagine you'd, imagine what it's like to touch felt, or to touch chinchilla hair or something like that. A chinchilla's hair, ideally a live chinchilla st- sitting still. Those little critters move really, really fast, but they have very, very soft hair. High hair density, so soft. Okay. Most people can do that. About 5 to 15% of people are less able to do that, and there's a small percentage of people in that 5 to 15% that simply cannot do it at all, that just cannot visualize well. We'll talk later about these people. They have what's called aphantasia, an inability to mentally visualize. But most people are actually pretty good at visualizing things when they are told what to visualize, and, and this is a really key point, and if what they are told to visualize is very simple and the whole visualization is quite brief, lasting on the order of about 15 seconds to generate the visualization in the auditory or in the visual aspect of one's mind's eye or ear, if you will, and if it's repeated over and over. What's far harder for everybody to do, and in fact what most people simply cannot do, is imagine long, extended scenes and stories in their mind that go on for minutes and minutes and involve a lot of different sensory stimuli. This is a really key point. In fact, as we start to home in on ideal mental training and visualization protocols, I'd like to establish this as the first principle of mental training and visualization, which is that if you are going to use mental training and visualization to its best effect in order to engage neuroplasticity and learning, you need to keep those visualizations quite brief, really on the order of about 15 to 20 seconds or so, and pretty darn sparse, meaning not including a lot of elaborate visualization, not including a lot of sequences of motor steps. What I mean are motor sequences, if you're trying to learn something in terms of physical movement, or visual sequences or auditory sequences, if you're trying to learn things in terms of music or dance, et cetera, that can be completed and repeated in 15 seconds or less. Now, later I'll give you a couple of specific examples. But if you want to use mental training and visualization, understand this is the key first principle. They have to be very short visualizations that you can repeat over and over and over again with a high degree of accuracy. So, you don't want to embark on a mental training and visualization paradigm in which it involves a lot of elaborate stimuli and you have to think really hard and work really hard, even if you're in that category of people who can do mental visualization pretty naturally and easily. Now, if you're somebody who can't do mental visualization, in fact, if you're somebody who has full-blown aphantasia or the inability to mentally visualize, well, then it's especially important that you make those mental trainings and visualizations really brief and very,

Andrew Huberman 29:36 very simple. I'd like to take a quick break and acknowledge one of our sponsors, Athletic Greens. Athletic Greens, now called AG1, is a vitamin mineral probiotic drink that covers all of your foundational nutritional needs. I've been taking Athletic Greens since 2012, so I'm delighted that they're sponsoring the podcast. The reason I started taking Athletic Greens and the reason I still take Athletic Greens once or usually twice a day is that it gets me the probiotics that I need for gut health. Our gut is very important. It's populated by, uh, gut microbiota that communicate with the brain, the immune system, and basically all the biological systems of our body to strongly impact our immediate and long-term health.And those probiotics in Athletic Greens are optimal and vital for microbiotic health. In addition, Athletic Greens contains a number of adaptogens, vitamins, and minerals that make sure that all of my foundational nutritional needs are met, and it tastes great. If you'd like to try Athletic Greens, you can go to athleticgreens.com/huberman, and they'll give you five free travel packs that make it really easy to mix up Athletic Greens while you're on the road, in the car, on the plane, et cetera, and they'll give you a year's supply of vitamin D3K2. Again, that's athleticgreens.com/huberman to get the five free travel packs and the year's supply of vitamin D3K2.

Andrew Huberman 30:51 Now, in order to develop the best mental training and visualization protocols for you, let's go a little bit deeper into what the research says about mental visualization. Now, the classic work on mental visualization really hinges on a number of different researchers and their work, but in particular, Roger Shepard, who did this work at Stanford, and Stephen Kosslyn, who's now at Harvard. There are, of course, others in the field, but it's really the work of Shepard and Kosslyn that lay the foundation for our understanding of what happens in the brain when we mentally visualize something. Shepard did these incredible experiments in which he had students mentally visualize simple objects, like a square, like a triangle, and he measured how long it took them to do that. Now, of course, at the time when he did these experiments, there were no sophisticated brain imaging devices and machines like fMRI. However, everything I'm about to describe has been later confirmed using things like fMRI. What Shepard did and what he found is that if people were told to visualize very simple objects, they did it pretty quickly. However, if they were told to visualize more complex objects, or importantly, to rotate those objects in their mind's eye, well, then it took longer for them to perform those mental visualizations. Now, many of you might think, "Duh, if I have to just imagine a triangle or a cube, that's going to be very easy and very fast, whereas if I have to rotate that triangle or cube in my mind's eye, that's going to take more time." And indeed, that is somewhat of a duh, except, and this is so very important, except that what Shepard and his colleagues found is that how long it takes somebody to generate and rotate a given visual image scales directly with the complexity of that image. In fact, Kosslyn did some experiments that I think illustrate this even better, and here's the experiment. I love this experiment, and I think you'll love it too, because it illustrates something so fundamentally important about how our brains work, not just for sake of mental training and visualization, but just how our brains work at all. He showed people a picture of a map, so a map drawn on a piece of paper. This was a map of an island. It included things like a loading dock for some boats. It had a location for getting food on the island. It had some trees. It had some other small landmarks drawn out, and people looked at this and memorized it. Or, in other experiments, they just had people imagine this island and the location of these different landmarks on the island. So d- didn't really matter which. But then, he had people imagine moving or walking from one location on the island to another. So they'd say, "Okay, you're at the loading dock. Now, move to the restaurant. Okay, you're at the restaurant. Now, move to the palm tree. You're on the north shore of the island. Now, go around the side of the island clockwise to arrive at the bay on the southwest corner," this sort of thing. What Kosslyn found was absolutely incredible. What he found was that the amount of time that it takes people to move from one location on the map to another scaled linearly, directly, with the actual physical location between those objects on the map. So for those of you that can understand or are into the importance of what Shepard and Kosslyn showed, great. I'm guessing, however, that for most people out there, you're still grasping at, like, "Okay, interesting, you know, how things happen in the real world dictates how they happen in our mind's eye," but I want to make sure that I really nail home the importance of this for everybody. The importance of this is that when we look at something in the real world, so if I look at the pen in front of me, I'm holding up my pen, for those of you that are listening, just holding up my pen in front of me, and I move it to the right and back and forth, what's happening is I'm activating or I'm triggering the electrical activity of neurons, which we can think of kind of as pixels in my eye, okay? So it's, you know, leftward to rightward motion for me and back and forth, and those are getting activated, and they're sending signals up to my visual cortex, and that information is processed at a given speed. What the visualization experiments that Shepard and Kosslyn and others did show is that the processing speed of imagined experiences is exactly the same as the processing speed of real experiences. And the spatial relationship between imagined and real experiences is exactly the same as well. Put simply, when we imagine something in our mind's eye or mind's ear, we are imagining the real thing happening. And when I say the real thing, it's not the obvious real thing. Of course, if you're imagining something, that's the thing you're imagining. What I mean is that your brain, at the level of neurons, is behaving exactly the same way. And this needn't have been the case, okay? There could've been a result, for instance, that if people were asked to visualize a cube and rotate it from, you know, flip it from top to bottom, okay, so put the top that's upward on the table now down on the table, and so forth, or to migrate around the island, you know, c- counterclockwise going from, you know, the northern coast all the way down to the southern coast clockwise and then back up to the northern coast, that they could've just done it really quickly, like, phew, all in one second. But that's not what happens. They always match the speed at which they do things in their mind's eye.... to the same speed that they do them in the real world. So, in telling you this, what I'm saying is that mental visualization at the neural level is identical to real-world events. So, when you've heard that when we imagine something, it's identical in terms of our brain's experience of it, and our body's experience of it, as when we actually experience something, that is true at the neural level. However, when it comes to learning and improving performance in the cognitive or physical domain, they are not equivalent. So, this is the second principle of mental training and visualization. As you recall, the first principle of mental training and visualization was that in order to make it effective, it needs to be very brief and very simple, and repeated over and over again. The second principle of mental training and visualization is that while, yes, mental training and visualization recaptures the same patterns of neural firing in the exact same ways as real-world behavior and thinking, it is not as effective as real-world behavior and thinking. In other words, if you want to learn something, the ideal situation is to combine real training in the physical world with mental training. And I'll talk about exactly how to do that and in what ratios a little bit later. Now, there's

Andrew Huberman 37:36 a really incredible set of experiments that illustrate why it is that mental training and visualization can be extremely effective, but that it's always going to be most effective when combined with real-world training and experiences. The experiments that I'm talking about involve the use of what are called bistable images or impossible figures. Uh, some of you are probably familiar with impossible figures. These are figures or objects that, when you look at them, they have these odd features, like you're not sure where they stop and where they start or where they end. Uh, one good example would be the so-called Mobius strip. The Mobius strip is literally a strip or a line that is contiguous. It goes up and it loops around, and then it curves around and then it goes back, and it- and it just continues and continues. And when you look at it, you can never really tell where it starts and where it stops, because it doesn't have any of the features that allow you to see what's the front and what's the back in any kind of stable way. Another example of an impossible figure would be, you know, a little, um, set of cubes that look like they're coming out toward you, maybe with a little c- uh, bend in them, going up at a right angle perhaps. But then if you look at it a little bit longer, that little piece that's facing up looks si- like it's in front, and you can't really tell what's in front and what's in back. And so, it's called an impossible figure because you don't really know how to frame it in your mind to tell what's closer to you and what's further apart. Bistable images are somewhat similar, although different in the sense that they typically are simple silhouettes. So for instance, the faces-vases bistable image is perhaps the most famous of these, where you look at this image, it's very simple, and it looks like two vases. But then you look at it a little bit longer and you realize that you're looking at the s- side angle or the profile of two faces looking at one another. And when you see those two faces looking at one another, you can't see the vases at the same time. But then if you decide to see the vases again, you can see the vases again, but the faces disappear. So, it's bistable, meaning that you can't see the faces and vases at the same time. And impossible figures and bistable images are capturing the fact that your visual cortex and some of the associated areas that compute visual scenes in your world are essentially trying to recreate whatever it is that's out in front of them, and that's effectively what your visual system does. It's very good at recreating visual images in your brain, in your mind's eye. Because if you think about it, even with your eyes open, your brain is just creating an abstract representation of what it thinks is out there. But that when it comes to assigning an identity to something, like, "Oh, that's a face," or, "Oh, that's a vase," that is constrained by different neural circuits, by different areas of the brain, and somehow those circuits can't be co-active. We cannot see the faces and the vases at exactly the same time. We can switch back and forth really quickly, just as we can switch back and forth really quickly when we're looking at the impossible figure and think, "Okay. That's the front of it, that's the back. No wait, that's the back, that's the front." And it's going back and forth, but we can't see them both at the same time. No one can see them both at the same time. Okay? We know this from brain imaging studies. Now, impossible figures and bistable images can be seen, right? You could look them up right now on your phone or computer, or I could show you pictures of them on paper right in front of you, and you can do these sorts of perceptual experiments of telling people, "Look at the face, look at the vase. Look at the front of the cube. Now make it out the back of the cube." And they can do this somewhat deliberately. However, and this is (laughs) I think so very interesting to understanding how mental training and visualization does and does not support real-world learning, if you try to imagine a bistable image, you can't do it. In fact, no one can do it until they do something else. Okay? So, for those of you that are saying, "Wait, I can do it. I can do faces-vases in my mind's eye," I promise you that the neuroimaging disputes your belief, okay? And supports the idea that we can see real world bistable images, we can see real world impossible figures, but when we try and imagine those in our mind's eye, we simply can't do it. We can't do the perceptual shift in our mind's eye. We can't switch back and forth between faces and vases. However, (laughs) and I just have to chuckle 'cause I think these experiments are so clever, if I have you trace or draw with a pen on a piece of paper an impossible figure or the faces-vases bistable image and then I ask you to imagine that bistable image or impossible figure and to switch back and forth, you are able to do it. So, what that illustrates is that it's the combination of imagined and real-world experiences, real motor movements, real perceptual experiences combined with motor movements, combined with what you imagine in your mind's eye, that really gives you the most depth.... and flexibility over your mental visualization. And in doing so, we can really stamp down a third principle of mental training and visualization, which is that your mental training and visualization will be far more effective if you are performing the exact same or very similar mental and physical tasks in the real world. Okay? So first principle is mental training and visualization needs to be simple and brief and repeated. Second is that mental training and visualization is not a replacement for real world motor training or cognitive training. It's an augment. It's an addition that can really help. And the third principle of mental training and visualization is that you need to combine mental training and visualization with real world behaviors and experiences that are very, very

Andrew Huberman 43:17 similar. Now, as a brief, but I think really relevant aside, one of the things that also makes mental training and visualization more effective is when we assign cognitive labels to what's going on when we visualize. So what I mean is that people are much better at manipulating faces and vases in their mind's eye, of course only once they've drawn them out physically with their hand, as I mentioned before, than they are manipulating abstract objects like impossible figures, in part because by labeling them faces and vases, people are able to capture a lot of other neural machinery that's related to faces and vases. In fact, we have entire brain areas on both sides of the brain devoted to the processing of faces, they're called fusiform face area. We have other areas in our brain that are involved in processing of 3D objects, but faces are of particular value. There's a, there's a value to understanding what a face is as opposed to a non-face, and there's a value to understanding what a particular face is. In fact, the simplest way to put this is that the human brain is, in many ways, a face recognition, an expression of faces recognition machine. It of course does other things, but it is exceptionally good at that. Unless you're in a profession in which the relationships between 3D objects and your ability to manipulate them is exceedingly important, you're not going to have a lot of neural real estate specifically devoted to that. Some people will be better at it, some people will be worse, but when it comes to faces, unless you have a condition like prosopagnosia, which is an inability to recognize, say, famous faces and distinguish them from non-famous faces, or if you have some sort of face recognition deficit, which about anywhere from 1 perhaps to 3% of people out there have, you know, they're just terrible at recognizing faces. And by the way, there's about half a percent of people out there that are what are called super recognizers that can recognize faces in a large crowd, they can recognize specific faces even from just partial profiles. By the way, these people are extremely valuable to securities agencies, and security agencies are very good at finding these people. Um, machines are quickly getting better, or at least as good as super recognizers, but the best super recognizers are still better than the best AI and machine algorithms out there. But the point is that, in your mind's eye, you are better able to manipulate specific objects or to see things more clearly and with more specificity when it has a label that you recognize from your real world experience, as opposed to abstract or fictional labels, okay? Again, stamping home the idea that what you experience in the real world really serves to support your mental imagery, and therefore the key importance of experiencing and doing things in the real world and supporting that with mental training and visualization and not just relying on mental training and visualization. And the tangent here that's a little bit of fun, and I don't think we've ever talked about before on this podcast, is that of UFOs, unidentified flying objects. You know, there's a lot of people out there who think that they've seen UFOs. I guess technically they have, because a UFO is an unidentified flying object, and if it's unidentified, at least to them, then it is indeed a UFO. I guess the question is whether or not, uh, or the dispute rather is whether or not those UFOs are actually flown by aliens or controlled by aliens. I think that's where the dispute lies. But you can imagine how if somebody sees an object in their environment and decides, "Ah, that's a UFO," okay? Remember these faces vases or these impossible figures? If they say, "Oh, that thing is a UFO" as opposed to something else, they see, in other words, the face, not the vase, well, that stamps it down as a memory in their visual system and related systems, and then in their mind's eye, they are seeing the UFO. They're not seeing the other thing that it could possibly be, okay? So it stamped on a very specific memory. So the point here is that mental training and visualization relies on not just the physical contours and the exact spatial profiles and the speed of movement of particular things that we experience in the real world. It also heavily depends on the cognitive labels and the decisions we make about the things that we see. And this will become very important as we build up toward our fourth principle of mental training and visualization, which is that our cognitive labels, that is what we decide is happening when we do mental training and visualization, turns out to be very important. Now, this is not simply to say that you can decide, "Okay, I want to learn how to play piano, and so I'm going to tell myself that a particular chord I imagine in my mind's eye is identical to the real world chord just because I decide it is." The brain doesn't work that way. It's not possible to just lie to yourself and learn better as a consequence of the lies you tell yourself. However, what this tells us is that it is very, very important that your mental training and visualization accurately recapitulate the real world training that you're doing. So we are going to stamp down a fourth principle of effective mental training and visualization based on what we know from the scientific literature, is that your mental training and visualization should assign labels to what you're doing that can be matched to real world training and experiences. Now, these can be somewhat abstract. So for instance, if you're trying to learn...... a particular aspect of the golf swing. Okay? So let's say that you're working on your golf swing. Seems to be there are a lot of people out there working on their golf swing. And you're going to do some mental training and visualization in order to improve your golf swing. We already know, again, let's just march through them, that your mental training and visualization needs to be brief and simple, it needs to be the same or, in fact, it will be, we can say, the same as your real world golf swing. In other words, it will take you exactly the same amount of time to perform that golf swing in your mind's eye as it would in the real world. Incredible, right? Again, something that maybe is taking a little bit of time to sink in, but once it does, you're gonna be like, "Wow, the brain is really an incredible machine." And that third principle, that you still have to do golf swings in the real world in addition to the mental training of golf swings. And fourth, that if you want that mental training and visualization to really improve your golf swing, you're going to have to name or apply an identity to the specific golf swing or aspect of the golf swing that you're practicing. So, this could be abstract. You could call it mental training and visualization of golf swing 1A, and you could imagine in your mind's eye, you know, the perfect golf swing over and over and over and over. But then when you're in the real world, you're also going to have to call that, either out loud or just to yourself, golf swing 1A. Okay? As opposed to a putt, which might be 1B. So naming and giving an identity to a real world skill and applying the same name or identity to the mental version of that, the visualization of that, can enhance the mental training and visualization in significant ways. So when we apply identities or names to these mental trainings and visualizations, and again, provided that they are brief and repeated and so on, we greatly enhance the amount of neural machinery in the brain and body that we are able to recruit when we go to perform those real world golf swings and golf putts. And here just replace golf swing and golf putt with anything that you're trying to learn. You're able to recruit a lot more neural machinery and greatly increase the probability of proper execution.

Andrew Huberman 50:37 So before we go any further, I wanna share with you a couple of incredible aspects of mental visualization that really can be harnessed and applied toward mental training and visualization. Okay. Some of these were done by Roger Shepard and his graduate students and post-docs, some were done by Steve Kosslyn and by others. What these experiments really show is that mental training and visualization is capturing many, many of the exact same features of real world behavior and perceptions. Not all of them, but many of them. So for instance, if I tell you to close your eyes and imagine a ceiling that has tiles that are black and white checkered tiles, you know, one black tile, one white tile, for instance. We know based on experiments where we measure eye movements behind closed eyelids that people tend to move their eyes up when they're imagining things above them, such as a ceiling. Whereas if I tell you to imagine things down on the floor, like you're taking a hike and you're looking for, uh, rattlesnakes... Actually, just recently I experienced, because it's spring here in California, rattlesnake along a hiking trail. It was really quite beautiful, although I, um, have to confess, I enjoyed keeping my distance. Uh, I don't like snakes, uh, very much. I don't dislike snakes, but I prefer not to interact with them unless I have to. If I have you imagine that rattlesnake, depending on your relationship or thoughts about rattlesnakes, number of things will happen in your brain, of course, activation of the limbic system or not, for instance. But what I know is that regardless of how you feel about snakes, most of you will move your eyes down when imagining a snake. Okay? It might be subtle, it might be fast, but statistically, that result shows up. As opposed to when I imagine or I ask you to imagine something above you, you tend to move your eyes up. In addition to that, if I tell you, for instance, to imagine an elephant and a mouse next to one another, you presumably have some real world understanding about the relative sizes of elephants versus mice. Elephants generally are bigger than mice, thank goodness. Mice are smaller than elephants. If I ask you to tell me about the details of that mouse's face, so for instance, can you see its whiskers, the processing time required for you to do that is much longer than the processing time required if I say, "Tell me what the position of that elephant's trunk is." Now, why would that be so? Okay. The position of the elephant's trunk wasn't something that I told you. It wasn't dictated by me. It's in your mind's eye. Maybe you don't even know and you have to go searching for it. But what we do know is that if I tell you to look at a small object in your mind's eye versus a larger object, so for instance, the mouse versus the elephant, it takes longer for you to do that. In other words, just as with the map experiment, the distance between things on a map is conserved in your mind's eye as a linear relationship, takes longer to go far distances between things on a map in your mind than it does to go shorter distances. It's also the case that it takes you longer to look at the details of a small object versus a large object, because why? Because you are zooming in in your mind's eye. Again, all of which speaks to the equivalence of mental imagery with real world imagery and perception. And as I mentioned earlier and as we'll see in a moment, this also extends into the motor domain. It takes you longer to perform complex motor sequences in your mind's eye than it does simple motor sequences, just as it would in the real world. And if you're saying, of course, of course, of course, well then great, then we've really underscored the point which is that when you imagine things, it is not exactly the same but it is very, very much the same as actually doing or perceiving those things in the real world. And the fifth principle of effective mental training and visualization is this notion of equivalence of mental imagery versus real world perception and behavior.These are the experiments, as you recall, where if people are told to look for clouds in their mental visualization, they tend to look up, or if they're looking for something on the floor, they tend to look down, even behind closed eyelids. Now, this can be applied toward building an especially effective mental training and visualization protocol if you deliberately move your eyes in the direction of the thing or things that you are trying to recapitulate in your mind, in your visualization, that is. You don't necessarily have to include this step, but mental training and visualization is going to be more effective if you do, because with consciously generated eye movements, again, even behind closed eyelids, you are bringing about more of the neural circuitry that one would experience if you were to perform that particular cognitive task or motor task in the real world, which, as I mentioned before in principle number three, you need to be doing anyway separately from your mental training and visualization.

Andrew Huberman 55:28 So what we're talking about here is thus far five principles of mental training and visualization that are well-established from the scientific research literature. In fact, I haven't mentioned this, uh, quite yet, and I'll refer to some other references, but there's a wonderful systematic review of a large number of studies that have looked at mental training and visualization, what's effective, what's less effective across a bunch of different disciplines that include education, medicine, music, psychology, and sports. We will provide a link to this paper in the show note captions, but the title of the paper is Best Practice for Motor Imagery: A systematic literature view on motor imagery training elements in five different disciplines. As the title suggests, it's mainly for motor imagery training, but it extends into music, which of course involves motor training and execution, but as well as education. This review establishes a number of different important things. I'm going to read off some of the, um, key or, uh, highlight takeaways. For instance, I described principle one of effective mental training and visualization, which is that the visualization be brief and it be simple and it be repeated, may ask, um, how many times that very brief 5 to 15-second, uh, exercise of going through some routine should be repeated. Well, different studies have used different ranges of, let's call them repetitions in a given training session, but the number that seems to be most effective is somewhere between 50 and 75 repeats per session. That brings about the question of how long one should rest between each repeat. This gets a little tricky depending on what you're trying to do. Uh, remember that we have this kind of threshold of about 15 seconds for completion of the entire motor sequence. Let's say what you're trying to do, like a golf swing takes you five seconds to imagine in your mind's eye from the point where you, let's just say, have the ball on the tee, you bring the, the golf club up, you might reposition your, your feet just a little bit, you know, that kind of little wiggle that golf- golfers do, and then the swing. If that whole thing takes five seconds in your mind's eye and roughly five seconds in the real world, well then you'd be able to repeat it, of course, three times in 15 seconds. That would be one repetition, even though you're doing it three times, so it's one 15-second epoch as it's sometimes called EPOCH, epoch, and then you would rest for an approximately equivalent amount of time, 15 seconds or so, and then repeat, then rest 15 seconds or so, and then repeat, rest 15 seconds, and then repeat. Again, three golf swings within that 15 seconds, rest 15 seconds, three golf swings within that 15 seconds, rest 15 seconds. Truth told, these epochs and these rest periods do not need to be exact. You could imagine, for instance, that you get three repetitions of the swing within 14 seconds. Well then do you do another one or do you wait until the end of that 15 seconds? I encourage you not to obsess too much about those sorts of points. Rather, you want to do as many repeats as you can in about a 15-second epoch, and then rest for about 15 seconds and then repeat for a total of 50 to 75 repetitions, which might not sound like a lot to some of you, might sound like an awful lot to others of you. To me it sounds like a lot, you know, 50 repetitions of something in where you're trying to concentrate in your mind's eye on getting something accomplished over and over, over again in exactly the same way might seem like a lot. We know based on the learning literature that your ability to successfully perform something in the real world will lend itself to better performance of that thing in the imagined world within your mind's eye. That's also one of these sort of does, but if you're trying to get better at something that you've never performed before, you really should know that. The mental training and visualization is probably not the best augment to that real world training until you're able to perform it successfully in the real world at least some of the time. Mental training and visualization can be effective, however, at increasing the accuracy or the frequency at which you can do that real world behavior. So if normally you're only getting the correct swing or you're only hitting the, the golf ball correctly say 10% of the time, mental training and visualization can really help bring that number up, but it is important that you are able to successfully complete that motor task in the real world. Similarly for performance of cognitive tasks, so say for instance, um, uh, speaking a new language, uh, you might ask, "Well, gosh, w- what in the landscape of speaking a new language can be restricted to 5 to 15 seconds where I could repeat it anywhere from, you know, thr- one to three times in a given epoch and then rest and then keep repeating 50 to 75 times?" Well, there I would encourage you to pick something that you are able to do perhaps very slowly, so to speak a particular sentence, but with some challenge in getting the accent and the enunciation right, but you've completed it successfully before and you want to get more smooth or more fluid with it. Likewise for, you know, playing piano or guitar. Again, you have to translate to the specific cognitive and/or motor activity that you are seeking to improve at, but-Those epochs lasting five to fifteen seconds are really the cornerstone of an effective mental training and visualization practice. And the re-repeated nature of it, fifty to seventy-five repetitions in a given session, is also another cornerstone of an effective mental training and visualization practice. Uh, so says this review, and some of the other papers that I'm going to get to in a few moments. (smacks lips) Now, one of the other key components of a successful mental training and visualization practice is how often you perform that mental training and visualization practice. And again, uh, a number of different studies have looked at this, uh, through a number of different lenses, meaning anywhere from two to eight times per week. It does appear that performing these sessions anywhere from three to five times per week is going to be effective. We could perhaps even say most effective, because most of the, uh, let's just call it the strongest data really point to repeating these fifty to seventy-five trials of the same thing three to five times per week. So, you can come up with a number that's reasonable for you to do consistently. And you might ask, "Do you have to continue to perform the mental training and visualization forever?" And the good news is, the answer to that question is no. It does seem that once you have what's called consolidated the motor performance or the cognitive performance of something, it can be further supported or reinforced, that is, consolidated in the neural circuits that are responsible for performing that mental or physical task. So, in other words, once you are performing that cognitive or motor task in a way that's satisfactory or perhaps just improved, perhaps you're not a hundred percent, but it's improved in the real world, you don't need to continue to do mental training and visualization to f- to maintain that real-world performance. So, that's a good thing. In fact, the ideal situation would be then to pick a different sequence or thing that you're trying to learn and do mental training and visualization for that. Uh, I perhaps might have misspoke there, although I don't want to edit this out. I misspoke in the sense that, again, I said for the thing that you're trying to learn, remember, mental training and visualization is going to be most effective for building up the number of accurate trials or that your ability to do something with a greater frequency of something that you're already capable of doing or have done at least once in the real world. Okay? This is not to say that mental training and visualization can't be used to acquire new skills. It can in principle, but it has been shown to be most effective for enhancing the speed and the accuracy of skills that one has already demonstrated some degree of proficiency at in the real world. I think that's important to point out because we often hear mental training and visualization and this equivalence of perceptual and motor experiences in our mind's eye to the real world, and we think, "Oh, all we have to do is imagine doing something, and we will get better at it." And unfortunately, that's not the case. The good news is, however, if you can do something once, even very slowly in the real world, and then you bring it to the mental imagery and visualization domain, you can get much faster at it in a way that really does translate back to the real world.

Andrew Huberman 1:03:43 I'd like to just take a brief moment and thank one of our podcast sponsors, which is InsideTracker. InsideTracker is a personalized nutrition platform that analyzes data from your blood and DNA to help you better understand your body and help you reach your health goals. I've long been a believer in getting regular blood work done for the simple reason that blood work is the only way that you can monitor the markers, such as hormone markers, lipids, metabolic factors, et cetera, that impact your immediate and long-term health. One major challenge with blood work, however, is that most of the time, it does not come back with any information about what to do in order to move the values for hormones, metabolic factors, lipids, et cetera into the ranges that you want. With InsideTracker, changing those values becomes very straightforward because it has a personalized dashboard that you can use to address the nutrition-based, behavior-based, supplement-based approaches that you can use in order to move those values into the ranges that are optimal for you, your vitality, and your longevity. InsideTracker now includes a measurement of apolipoprotein B, so-called ApoB, in their Ultimate Plan. ApoB is a key marker of cardiovascular health, and therefore there's extreme value to knowing your ApoB levels. If you'd like to try InsideTracker, you can go to insidetracker.com/huberman to get 20% off any of InsideTracker's plans. Again, that's insidetracker.com/huberman to get

Andrew Huberman 1:05:00 20% off. Now, if you recall principle number three, or what I'm calling principle number three of effective mental training and visualization, which was that you have to be able to perform the thing you're- that you're trying to get better at through visualization and imagery in the real world. That should raise the question of what is the ratio of real-world training versus mental training that's going to be most effective? Ah, well here there are some really interesting data (laughs) , uh, not just in the review that I mentioned, but in a couple of the other papers that we're gonna talk about in a few minutes. But what I've done is I've synthesized the information across those papers, and they really all point to the fact that real-world training is more effective than mental training, and mental training is more effective than no training. Now, the mental training more effective than no training is kind of a duh, except that there are people, for instance, people who are injured, who are trying to maintain or replenish some motor skill or ability to move in a particular way, or who have had, uh, traumatic brain injury and are trying to recreate experiences in a way that's safe for them while in a somewhat restricted format. So, for instance, if you've damaged a limb, or you're experiencing chronic pain, and you need to take a layoff from some physical activity, there are now many studies, uh, looking at stroke patients, at, um, patients that have been in accidents, TBI, also people who are suffering from more conventional limb and connective tissue injuries, that if they do mental training, it obviously is not going to put them at risk of doing those same movements as it would in the real world.... right? But that it can actually accelerate or at least maintain skilled performance. So this is pretty exciting if you think about it. What this means, and the reason it underscores this mental training is better than no training, is that should you find yourself in the unfortunate circumstance of being injured or unable to perform a given behavior, imagining the sequence of behavior that you'd like to maintain or even build up over time, provided you've done that motor sequence before in the real world, well, the mental training and visualization can really help keep that online or even help you improve over time. In fact, I have a colleague in the psychology department at Stanford who told me an anecdote, and a- admittedly it's just an anecdote, of a student who was recruited to Stanford, uh, both for their academic prowess but also for their abilities in tennis, and was injured in their first year, and at first thought this was devastating, but did a cognitive reframe around the idea that that, let's call it extended layoff from actual tennis, was going to afford them the ability to do more mental training than they would otherwise, even though they were, um, quite sad to not be able to do actual physical training for tennis. And when they came back from that injury, they did indeed manage to improve beyond the initial non-injured state they were in before the injury, which is pretty remarkable. But, as this colleague pointed out to me, they were very careful to include a lot of mental training and visualization during that, quote-unquote, "layoff" period. So again, mental training better than no training, physical training better than mental training, but when we say physical training better than mental training, what we're really talking about is when you allocate a certain amount of training hours for a given skill per week. Okay, so how would this look? What these studies have done is they've said, "Okay, if people have the option of doing the real world training for 10 hours a week versus mental training for 10 hours a week, which group performs better?" And it turns out, it's the ones that do the physical training for 10 hours per week. However, we also know that combinations of physical training and mental training can bring about results that are greater than either one of those alone. How would that work? Well, I wish I could tell you that if you did nine hours of physical training per week plus one hour of mental training that your performance would be better than if you did 10 hours of physical training, and that's not the case. Okay? This is why we can reliably say physical, real world training, and again, this could be in the cognitive domain, is always going to be more effective on an hour-by-hour basis compared to mental training. So if you can do real world training, and perhaps we should be calling it real world as opposed to physical, but if you can do real world training compared to purely mental training, that's going to be the best use of your time. This is really important. And it doesn't underscore everything that we're talking about, because here's the really cool thing. If you do 10 hours per week of real world physical training, again, could be running, could be music, could be math, could be whatever it is you're trying to lo- learn, shooting basketballs, hitting golf balls, and you add one hour or even half an hour of mental training to that f- real world training, well then the results are significantly greater than you would experience with physical training alone. And of course, it would be greater than you could achieve with mental training alone because we already established that real world training is more powerful in learning skills and retaining skills than is mental training. Okay, if any of that was confusing, let me just say it one more time just to be ultra-clear. If you have the option to do real world training for a cognitive and/or motor skill versus mental training, always go with real world training. However, if you can add to a maximum amount of real world training by doing some mental training, and you follow the principles that we've been discussing here, which are gleaned from the scientific literature, well then you are going to get significantly greater results in terms of speed, accuracy, and consistency of performance of those real world behaviors and c- cognitive abilities. And of course, if you are unable to do physical training for whatever reason, injury, travel, whatever the case may be, well then doing mental training is still far significantly greater than doing no training at all. Okay? So total layoffs, it turns out, are a bad thing if you want to get better at something and indeed if you want to retain certain skills, both cognitive and motor.

Andrew Huberman 1:11:09 Now a couple of other things to keep in mind as you're thinking about how to build up skills through a combination of physical and mental training. Well, remember back to the beginning of the episode where we talked about neuroplasticity, and the fact that self-directed adaptive plasticity, which is really what we're talking about here in this entire episode, things that you're trying to learn in an deliberate way, that is, as you recall, a two-part process. It requires focused attention both when you're doing it in the real world and when you're doing mental training, and it requires rest and sleep. And in fact, you would be very wise to try and get a good night sleep both on the days when you do physical training, again also called real world training, and mental training. You may also be asking, "Can you do them on the same day?" And this gets into some nuance in the literature, but by my read of the literature, here's the takeaway. If you are doing the maximum amount of physical training that you can do according to your schedule, preventing injury, and all those sorts of important constraints, and you're going to add mental training and imagery, it doesn't really matter when you do it. You could do it immediately after your physical training, you could do it on a separate day, but you do want to place it at a time in which you can try and get good sleep that night. So for instance, believe it or not, studies have been done where people are doing mental training at times when they should be sleeping. That is going to offset some of the degradation in performance that you would normally see, but it's generally a bad idea. You should do your real world training and your mental training-... whenever it is that you can, and then you should try and get as much quality sleep as you possibly can on the night following that physical and/or mental training. Okay. This is true of pretty much every night of your life, right? If I had my way, that is if I had a magic wand, which obviously I don't, I would ensure that I and everyone else in the world get sufficient amounts of quality sleep every single night, but that's just not realistic. There are going to be times where that's simply not gonna happen for whatever reason. And I always say if you're not going to get sufficient amounts of quality sleep for whatever reason, try and make it for a fun reason or a good reason. But I think getting sufficient amounts of quality sleep 80% of the nights of your life is a reasonable goal, and one that's worth striving toward. And we have lots of episodes now, or three really, on mastering sleep, on perfecting your sleep, and, uh, episode, guest episode with the great Matthew Walker, uh, who wrote the book Why You, Why We Sleep. I- incredibly important book. All of those, as well as our toolkit for sleep, describe ways to improve your sleep, so you can refer to those episodes if you're having challenges with sleep and want to improve on sleep, and things like non-sleep deep rest, which can support your ability to sleep and your ability to learn. So, sleep is still vitally important, not just for ensuring neuroplasticity occurs following real world training, but also following mental training. And again, when you place that mental training is not so critical, at least it doesn't appear to be based on the literature. So, if anyone out there has knowledge of any peer-reviewed studies stating that mental training should be done either before or after or some hours away from real world training, please send that to me, or put it in the sho- um, excuse me, put it in the comments on YouTube and I'll see it there, 'cause I do read all the comments. But I'm not aware of any, any such data or analysis. And by the way, if you are interested in understanding the relationship between motor skill acquisition and retention, and this first night phenomenon of sleep the first night after training versus sleep on the second night, et cetera, there's a really wonderful paper that was published by none other than the great Matthew Walker, when I believe he was a graduate student, maybe he was a postdoc when he did this in Robert S- Stickgold's lab at Harvard. Uh, the title of the paper is Sleep and Time Course of Motor Skill Learning. Uh, this is a paper published in 2003, uh, still an incredibly important paper. I will provide a link to it in the show note captions. It really highlights, um, some of the key aspects of when people sleep and how critical sleep is on the night following and the nights following that training in order to really consolidate certain types of learning and what phases of sleep relate to the consolidation of motor learning, et cetera. A really wonderful paper, and of course, but just one of Matthew and Robert Stickgold's incredible papers on sleep and

Andrew Huberman 1:15:17 learning. Remember at the beginning of the episode when I mentioned that many people are good at mental training and visualization, but some people are not? Well, sex differences have been explored and age-related differences have been explored in terms of people's ability to mentally visualize and train up specific skills. And while initially there were some sex differences identified, really the bulk of the subsequent literature, that is the majority of quality peer-reviewed studies on this aspect of mental training and visualization, point to the fact that there are no significant differences between males and females in terms of their ability to mentally visualize, nor their ability to use that mental visualization toward improving cognitive or motor skills. Uh, that point was, uh, covered in some detail in the review I mentioned earlier, Best Practice for Motor Imagery: A Systematic Literature Review on Motor Imagery Training Elements in Five Different Disciplines. This review also looked at age-related effects, and perhaps the only thing that really popped out from this literature review in terms of age-dependent differences that point at changes in protocols that you might make is that for individuals 65 or older, a combination of physical and mental training may actually allow them to gain and consolidate skills better than were they to do physical training alone. Now, whether or not that's due to some lower upper limit of physical training that they can do because of their age, or whether or not that's something specific to do with older versus younger neural circuits isn't clear, but what this review also makes clear is that for the vast majority of people out there, so teens, people in their 20s, in their 40s and so on, physical training more effective than mental training. We said that before. Combination of physical and mental training more effective than physical training alone, provided the mental training is on top of the maximum amount of physical training that one could do. And of course, mental training, more effective than no training at all.

Andrew Huberman 1:17:10 Okay, so we talked about sets and reps. We talked about, you know, five to 15 second epochs with about 15 second breaks in between, or rest between sets if you will, repeated for 50 to 75 trials, done three to five times per week, some of the conditions of keeping it really simple, the importance of being able to actually perform those sequences in the real world, and so on. What we haven't discussed is first-person versus third-person, and eyes open versus eyes closed. What are we really talking about here? Well, first-person mental training and visualization would be where you are imagining doing something and you are seeing yourself doing something from the inside out, as opposed from the outside in. Imagine, for instance, wearing a head cam, okay, or a body cam, and doing something with your hands, or being in virtual reality and having the sense that whatever you see in front of you and that's moving and that you're doing, that's you. So, what I mean by this is a mental training or visualization protocol, for instance if you were at the piano or at a guitar where you're actually looking down at or sensing the feeling of your hands, but you're not actually moving your hands, okay? As opposed to seeing yourself from outside of your body, so looking at yourself, say, standing next to you or from across the room, you're looking at yourself playing the piano or playing guitar or swinging a golf club or doing a tennis serve, okay? First-person versus third-person. And what the data tell us is that first-person mental training and visualization is generally more effective than third-person mental training and visualization, which perhaps raises another chorus of duhs out there, but it needn't have been the case, right? I mean, you could imagine that seeing yourself doing something and doing it perfectly, because you've done it perfectly once before hopefully, would allow you to build up that skill more quickly because you have that third-person perspective where you can really see every aspect and every element of what you're trying to perform.Well, turns out that the first-person mental training and visualization is significantly more effective than that third-person mental training and visualization. So, if what you're trying to learn lends itself well to this first-person mental experiencing of self as you perform the cognitive and/or motor skill, I suggest you do that as opposed to the third-person version. Now, what if what you're trying to learn doesn't lend itself well to first-person visualization? For instance, what if you're trying to learn a specific cognitive skill that doesn't involve any overt motor behavior to be observed? Well, in that case, it's very clear that closing your eyes, ideally, and trying to perform that specific cognitive task, or the statement, or the, you know, uttering of a particular sentence in another language, or doing some sort of computation or problem-solving of some sort in your head, well, that itself, of course, is first person because it's inside your own body. As opposed to, and I don't know that anyone would actually do this, but looking at yourself from a third-person perspective in your mind's eye and seeing yourself perform that cognitive challenge, whatever that challenge may happen to be, okay? Now, we have to address eyes open versus eyes closed, and this is where the literature gets pretty interesting. I always thought, for some reason, I don't know why, but I