Move your body, grow your brain: the science of hippocampal neurogenesis

After years of studying the hippocampus, the brain’s memory center, neuroscientist Wendy Suzuki made a surprising discovery: Regular physical movement dramatically improved her memory, focus, and overall cognitive performance.

Even 10 minutes of walking can trigger a powerful “neurochemical bubble bath,” boosting mood and mental clarity. From the science of long-term brain growth to the emotional benefits of movement, Suzuki reveals how exercise is one of the most effective—and overlooked—tools for improving brain health today.

WENDY SUZUKI: My name is Wendy Suzuki. I’m Dean of the College of Arts and Science at New York University and professor of neuroscience and psychology.

– [Narrator] Chapter one: Exploring the neurological effects of exercise.

– I have been fascinated with my favorite brain structure called the hippocampus for many, many years. Each of us have two hippocampi, one on the right, one on the left, and it is essential for our ability to form and retain new long-term memories for facts and events. And I became fascinated in this because of the most famous neurological patient of all time. His initials were, HM, we now know his name was Henry Molaison. And he suffered, as a young child, from epilepsy and got this experimental surgery where they knew that if you removed one of his hippocampi, it would improve the epilepsy, it would reduce the epilepsy, I should say. But because his epilepsy was so severe, they decided to remove both hippocampi. And that’s when they realized that while his epileptic symptoms were reduced, he was left with no ability to form any new memories of his entire life for facts, for events for the rest of his life. And that’s when we learned that the hippocampus was so important for memory. And I was fascinated with this, and I wanted to study the hippocampus. I started in 1998 as a bright-eyed, bushy-tailed young assistant professor at New York University studying the hippocampus and how new memories could be formed. What exactly does the hippocampus do when it helps you form these new long-term memories? And I was so excited to be able to do this, but in my excitement, I managed to unbalance myself. I don’t know if you’ve experienced this, but I just decided I was only gonna work because research professors on the tenure track have this thing we have to go through, getting tenure. It takes six years, and you have six years to make a big splash in science and discover something really, really amazing. So I decided that I was just gonna work. For six years, I was only gonna work and put my head down and get all the work done I can, trying to understand how the hippocampus forms new memories. And as you can imagine, I got unbalanced. I didn’t feel good. I didn’t have a lot of social relationships. I was eating too much takeout food, and I was just feeling so lethargic, and I knew I needed to do something about that. And that is what brought me to the gym because I didn’t know how to get more social relationships, but I wanted to feel better, feel stronger. I started eating better. I went to the gym. And a year and a half later, I felt so good. And I had this amazing realization. And a year and a half later, I had started going to the gym. I’ve lost 25 pounds by that point. And I thought, “Gosh, my memory seems to be working better.” In fact, I was writing a research grant, something that I do a lot. And I was sitting there, and I remember the day that I thought to myself, “Gee, that research grant writing, that went really well today.” I had never had that thought go through my mind in my entire career. And when I thought about it and I thought, gosh, my memory, my hippocampal-dependent memory that I was studying in my own lab, that seemed to be better. I was able to pull together details from all the papers that I was reading. And also my ability to focus, you really need deep focus, which is dependent on the prefrontal cortex right behind your forehead. That was also better too, leading to this better writing session. And that was the first day I started to realize that maybe it was this new level of physical activity that I was experiencing, that I was giving myself that was causing this really extraordinary change that my writing was going better. That was the first moment that I started seriously getting interested in how exercise might be affecting the brain and also helping the hippocampus, again, my favorite brain structure, important for memory. Because I studied the effects of exercise on the brain, people always wanna ask me about the runner’s high. What is it? How do you get it? And that’s a great jumping-off point, although I will be the first one to admit that the runner’s high is not available for most of us, including me, because I don’t run. I am a terrible runner, and so I can’t run, and therefore, I can’t get a runner’s high. However, it’s a great place to start because what it really is, is this feeling of euphoria that comes with running. The starting point for that is something that I like to call an insider tip from a neuroscientist who studied the effects of exercise on the brain. And here’s my insider tip number one, and that is every single time you move your body, including when you’re running, you are giving your brain what I like to call a wonderful bubble bath of neurochemicals. Those neurochemicals include dopamine, serotonin, noradrenaline, endorphins. And that cocktail of neurochemicals is what is giving the runners their runner’s high. We know that endorphins do play a really big part of that. But here’s the good news. You don’t have to be a marathon runner to get this. In fact, we know that even 10 minutes of walking can significantly improve your mood state, decreasing depression and anxiety levels, and improving positive mood states as well. So that’s where the runner’s high gets us to. And it’s one of the most powerful things that you can do for your brain today. Let me dive into that neurochemical bubble bath because it’s really the key to understanding exactly how exercise is affecting our brains. So I mentioned several things, several ingredients in that bubble bath that includes dopamine and serotonin and noradrenaline and endorphins. And that’s really key to the mood-boosting effects of exercise, but it also includes what’s called growth factors. Several different growth factors get released with movement, and that is going towards the long-term effects of exercise that can actually help grow and strengthen two key brain areas. One is the hippocampus, critical for long-term memory, and the second is the prefrontal cortex, critical for your ability to shift and focus attention. So how do we understand this? Every single time you move your body, you are releasing at least a part of that bubble bath. And that helps us understand how only 10 minutes of walking can improve our mood, decrease depression, decrease anxiety. And as you go up the activity scale to aerobic running and everything in between, you are getting those mood effects, why? Because you have higher levels of dopamine and serotonin, but that’s just the short-term effects. What about long-term effects? What if you give your brain a bubble bath on a regular basis for a week or a month or several years? That’s when those growth factors kick in. And what do the growth factors do? We know that the growth factors go directly to your hippocampus. The hippocampus is an extraordinary structure because it is one of the only human brain areas that can grow brand new brain cells in adulthood. And those growth factors help the hippocampus grow shiny, new hippocampal cells. And what does that mean? Your memory is better. So that is what you get with long-term memory. Oh, and I almost forgot to mention that the other brain area that benefits in terms of growth and strength is the prefrontal cortex. Now, it’s not growing new cells. Some evidence suggests that the outputs of cells in the prefrontal cortex called the axons of those cells perform better, work better with more exercise. They say that, for example, Serena Williams has really, really well-insulated axons in her prefrontal cortex because of all of that amazing tennis that she’s played for a long time. But those are some of the both immediate and long-term changes that you get with exercise that start with that neurochemical bubble bath. People often ask me, what is the brain-body connection? And it is the simple physiological idea that what you do with your body affects your brain. And what you think with your brain also has an effect on the physiology of your body. It works both ways. And so we’ve talked about moving your body, creating this neurochemical bubble bath that improves your mood and can grow hippocampal brain cells. That’s the body-to-brain connection. What about the other way? One of my favorite forms of exercise that I take and I teach is a form of exercise called intenSati that pairs physical movements from dance and kickbox and martial arts with positive spoken affirmations. It was developed by an amazing fitness instructor named Patricia Moreno. And there you are giving your brain this bubble bath, but at the same time, each movement is paired with a positive thought. For example, when you punch back and forth, we say, “I am strong now.” And imagine a class where the whole class is different moves with different positive affirmations. I can tell you that the first time I took this class, I walked out of that class feeling strong. I felt like Wonder Woman, Super Girl, all rolled up in one, because what you think and what you state verbally is what you start to believe. And that is why this particular workout is so powerful. It is taking full advantage of that mind-body connection that we’ve all heard about. That’s a way to take full advantage of it. One interesting question is, what is the difference between the brain of somebody that is more sedentary and the brain of somebody that is really active all the time? And again, what it is, is the neurochemical milieu or neurochemical bubble bath that their brain is bathing in. That is affecting their mood, that is affecting their energy levels, and ultimately, for the long-term, affecting the strength of particular brain areas, particularly the hippocampus and the prefrontal cortex. But never fear. You might say, “Oh, well, I’m in the sedentary camp. There’s no hope for me.” Here’s why there’s hope for everybody, and that is the principle of brain plasticity. Brain plasticity is this idea that the brain has an extraordinary capacity to change or modify its wiring based on the environment that you put the brain in, including the physical environment. Are you walking a lot? Are you running? Are you keeping yourself physically active? Are you learning new things? That also results in what I call positive brain plasticity. So using the same principles we’ve been talking about, what is the difference between a sedentary brain and the brain of a runner? Well, the runner’s brain has higher levels of dopamine and serotonin, kind of, boosted every single time that runner goes for a run. It elevates general mood state. Studies that I did in my lab showed that people that went to three months of spin class had overall higher mood states than people, for three months, who played video Scrabble. And so your overall mood state is better. Those people in the exercise group also have much more growth factors going through their brain. I like to think of it like a watering can of growth factors all up and down your hippocampi, what’s happening? They’re growing, popping, shiny, new hippocampal cells. Their memory is working better, and they’re getting bigger, fatter axons of their prefrontal cells, making their prefrontal cortex work better. But again, everything is fluid. With brain plasticity, even if you’ve been sedentary all your life, you can start moving towards that, what I like to call bigger, fatter, fluffier, and happier brain with just 10 minutes of walking, is what, kind of, can launch that change in your brain. People always tell me, “You are so good at motivating people to exercise, but then after I listen to your talk, I just go back home and sit on the couch and watch Netflix. What should I do?” Motivation is a key. And here’s what found in my own life as I transitioned from that unbalanced, unhappy pre-tenure faculty member that I was to a much more active faculty member. I started small, and I started with things that I already enjoyed, which, for me, was dance. I remember when I joined the gym, I decided I wanted to be more active. And like many people, I joined the gym, and I went to a hip-hop dance class. Okay, I love dance. I’m a terrible hip-hop dancer. And I remember coming out of that class saying, “Ah, God, that was embarrassing, but still fun.” I enjoyed doing it. So my tip, my motivational tip for everybody is start small and start with things you already know you like. If you hate running, don’t run. You don’t have to run. Or start practically. One of the things I did over the pandemic is I turned my weekly cleaning session into an exercise session. Have you ever seen that movie, “Mrs. Doubtfire”? Have you ever tried to do that choreography that Robin Williams did with the vacuum cleaner? It is hard. It is a great aerobic workout. And if you bring that play and that joy to even scrubbing the bathtub, it makes it more fun, it makes it more enjoyable and more aerobic. The other question everybody asks me at the end of my talks is, “That sounds great. I want a neurochemical bubble bath, but I really want you to tell me what is the least amount of movement that I have to do to get that neurochemical bubble bath.” And here is the answer based on actual scientific studies, and that is we know that as little as 10 minutes of walking can improve your mood, that is getting that bubble bath with the dopamine, serotonin, endorphins going. Anybody can do that. You don’t even have to change into your spandex. Go for a walk. You don’t have to change your shoes. Everybody can do that, wherever you live in this world, in this country. And so that is the minimum, but I love this, start small, everybody can walk, and then just add on. Can you walk a little bit more? Can you park a little bit farther away? Can you do another round of shopping with the big cart in Costco? That’s a great way to get exercise as well. For example, make it fun, practical. Oh, include your friends as well. I went to hip-hop, I didn’t go to hip-hop dance class, I went to dance class and found friends that I went to dance class with that made it even more enjoyable, even more motivating. I certainly check goals. And at the beginning of the year, everybody wants to have their, you know, beginning-of-the-year goals. I think those are, they tend to be bound for failure. And I instead, instead of at the beginning of the year, put all this pressure, I like to set smaller goals for myself, doable goals, goals that make me excited to try them. That is the key. And sometimes it takes a little bit of thought, you know. Maybe it’s not that, you know, those scary classes where you have to lift that tire up and push it across the room. But maybe it is a walk on the shore, a walk to the gym, a walk around the museum with friends. Be creative about the ways that you can, gardening, that’s another thing. People think those things don’t count. They all count. Moving your body, especially outside, all of that counts. Be more broad in your definition of bringing more movement into your life. Everybody wonders about what is the best time to work out. And my first answer to that question is always, anytime you could fit it in, fit it in. Don’t let the, oh, I’m doing it at this time and, you know, it’s not the best time, so I’m not gonna do it. Let go of that. Anytime you can fit it in from morning till night, fit it in. But if you wanna get a little bit more technical about it, here’s what I’ve learned from my studies of the effects of exercise on the brain. And that is that, as I said, every time you move your body, you are giving your brain this bubble bath. What exactly do you get? You get better mood, you get better performance on tasks that require your prefrontal cortex, which basically means you can shift and focus your attention better. And something I haven’t mentioned yet, your reaction time, your response time is better. And so I think about that. I’m reading all the papers, done the research on my own that confirmed all of those immediate things. And so here’s what I came up with. And also people ask, “Well, when do you work out, Wendy?” I work out first thing in the morning for several reasons. One is that it’s harder to have other things come get in the way of that, so it’s interrupted less. And two, I love the idea that after I work out first thing in the morning, I have this brain that is happier, that can focus attention better, and that responds quicker. That’s the brain that I wanna bring into my workplace first thing in the morning. And I did notice, so full disclosure, when I did this experiment, I was totally enjoying my after-work workout sessions. So I would reward myself, as many people do, go to the gym after work, and I loved it. But as I got into the research and I switched my research from memory to the effects of exercise of the brain, I thought, “Hmm, let me give this a try.” And I’m not gonna lie, it was painful to switch to first-thing-in-the-morning exercise. I was sleepy. I couldn’t follow the classes ’cause I was half asleep in class, and it was two weeks of pain before I got used to the new schedule. And then once I got used to it, I found that I could focus attention even longer in my day. For my whole life, I’ve always worked best first thing in the morning. I’m a morning person. And so that morning good work time got longer when I started and got used to that early morning workout. And you might say, “Well, I’m not a morning person, Wendy.” I totally get it. Try it. I love to advocate for personal experimentation. You know the science now that you’re giving your brain a bubble bath. It’s gonna make your focus work better. It’s gonna improve your mood. When are you gonna apply it in your life for how your life works? That’s how I applied it to mine, and I like to work out in the morning. You apply it to yours, and let me know how it works out. So many of us use caffeine. I’m not a coffee drinker, but I’m a regular tea drinker. And I think that to switch your exercise regimen goes beyond just the use of coffee or trying to use it, you know, to get yourself up. It’s really shifting your circadian clock, getting your body used to movement first thing in the morning. That’s what was so painful for those first two weeks that I tried it. So it really is being disciplined. If you wanna wake up earlier, you need to go to sleep earlier, and that is the hard part. You know, there’s always one more Netflix episode to watch. And you think, “Oh, it won’t do any harm,” but it will. And so it’s shifting that circadian clock and really sticking to it. I think, yeah, you can use caffeine as a crutch, but I think the sleep change and the, kind of, the timing change in your life and kind of getting the handle on that and again, what works well for you is the most important formula. There’s a lot of data on the idea that late-night workouts, I mean, they could benefit your body and you’re still getting that neurochemical bubble bath, but endorphins are not the best thing to help you fall asleep. And so, you know, you need time to cool down before you go to sleep. I experienced this myself. I never am able to go to sleep after I give an evening lecture. The later, the worst it is for me. I need several hours to come back down. And even though I usually go to bed at around 9:00, 9:30, if I’m giving a talk at 6:00 or 7:00, it takes me several hours to calm down and get into that restful state. And that is just, you know, energy levels. That is your fight-or-flight response coming online, increasing that adrenaline in your body and even that cortisol, and you can’t go to sleep with that level of that kind of neurochemical and hormone in your system. It simply takes more time to go to sleep. This is another situation where that personal experiment on yourself is notable. Journal about what works for you. You know, every single time I give a talk at 6:00 or 7:00, I need several hours. I’m not gonna get a good sleep. So do not schedule an early morning, you know, big important thing to do because I am gonna need to sleep in the next day. Find that for you. Journaling is great to notice those trends in yourself. But self experimentation, knowing some of the science behind it can be a very powerful tool to shift your life in the way that you want it to go. Here are my two motivations, and I’m a nerd so I have neuroscience motivations. Motivation number one, I love this idea of giving my brain a bubble bath of great neurochemicals first thing in the morning. I know it’s benefiting my brain, and I love the idea that part of those neurochemicals are growth factors because my favorite brain structure, the hippocampus, I know, is getting bigger and fatter and fluffier every single time that I work out. Why is that important? It’s because the hippocampus is one of the most sensitive brain areas to aging, and it starts to lose its connections. And I am motivated by making my own hippocampus as big and fat and fluffy as I can so that even if I get dementia, which I have in my family heredity, in my family history, that it’s gonna take longer for that dementia to have an effect of my memory, why? Because I made it big and fat and fluffy with my morning workouts. There are so many different brain benefits for exercise, almost too many to talk about. We’ve talked about the benefit long-term for the hippocampus. It grows new hippocampal brain cells, making it big and fat and fluffy. We’ve talked about the beneficial effects of exercise on the prefrontal cortex, another brain area very susceptible to aging, also increasing probably not brain cells, but the support cells, the glia cells seem to be benefited by exercise, and certainly the functions of the prefrontal cortex benefit from exercise. Mood is beneficial. Motivation is, I can’t point to the specific brain area that is important for motivation, but that positive habit that you create as you do regular exercise is a huge benefit for aging, just getting that positive habit into your life. Those are my top, how many did I name? Four. Hippocampal function: memory; prefrontal cortex: focus; mood; and motivation, all things that are benefiting from your regular exercise. One of the most interesting things in my research, I started with looking at the effects of physical activity on the brain. And I found, oh, decreased depression, decreased anxiety levels, increased focus, and then I and people, students in my lab got interested in meditation as well. So we did a very practical experiment. What would happen to people if they did just 13 minutes of a guided meditation every day for three months, compared to just listening to a podcast for the same amount of time for three months? We found same kind of benefits, better mood, decreased anxiety, depression levels, and better focus. So what’s happening there? How could the stillness have the same effect as moving your body and getting those neurochemicals going with movement? And the answer is, we’re still not sure, but those are the benefits. You can reap some of the same benefits from physical activity by bringing more meditation into your life. And today, it’s easier than it ever was to bring that into your life with all the award-winning apps out there. You can even go to meditation classes and group meditation classes, online meditation classes. I’ll tell you, I’ve tried it all. I’ve tried guided meditation. I’ve tried going to classes. I ended up finding a form of meditation that works beautifully for me, which is a tea meditation, which is meditation over the brewing and drinking of tea that I do every morning in silence. And the ritual of brewing and drinking tea, it has steps that you have to do in a certain order. Somehow that keeps me in the flow of the meditation. There’s always something that comes next. That’s, again, part of my self-experimentation. Sorry, Deepak and Oprah, I tried to follow your guided meditation. And you worked for a little while, but what worked best for me is this wonderful tea meditation. So try it, try that. Try the apps. See how you can find a moment and notice the benefits of silence on your mood and your focus. If I was appointed surgeon general tomorrow, here would be my message to everybody in the United States, everybody in the world, actually. And that is physical activity is the most transformative thing that you could do, not only for your body, but for your brain as well. That is the key message. And you don’t have to become a marathon runner, a triathlete to get these benefits because even 10 minutes of walking will start to give you immediate benefits in terms of decreasing anxiety levels, decreasing depression levels. That’s what everybody needs right now. And so my platform would be, move. Move more is the simple message that I would give for everybody because it’ll benefit your body and your brain.

– [Narrator] Chapter two: The formula behind exercise-driven brain optimization.

– The most common question that people ask is, you know, “Just tell me exactly what I need to do to get all those great brain benefits you talk about.” And in fact, they put their finger on exactly why I wanted to start to explore this. I was interested in that exercise prescription. What is the best form of exercise for me today to maximize my cognitive function? And perhaps even more importantly, what is that long-term exercise prescription that’s going to make my brain and keep my brain as big and fat and fluffy and healthy as it can be as I age? Well, I’m sorry to say that I don’t know the full answer to that question, but here’s the take-homes that I can tell you today, the science-based take-homes that I can tell you today. Take-home number one is something we’ve already said, which is the easiest way to start to reap the benefits of exercise in the brain is that 10-minute walk. Even 10 minutes of just walking can decrease your anxiety and depression levels. Again, something that everybody needs. That’s why when you can’t handle it anymore and you decide to go out for a walk, that’s why you feel better. It is that neurochemical bubble bath working. But what about those long-term effects? So we know that if you do correlational studies, and this is one of my favorite studies that was done in Sweden on a group of Swedish women. It was a 45 year follow-up study. So in the 1960s, they found a group of women in their 40s, and they characterized them as low-fit, mid-fit, or high-fit. And then 44 years later, they came back, and they can do whatever they wanted during those 44 years. 44 years later, the researchers came back, and they asked what happened to those women that were low-fit, mid-fit, or high-fit. And what they found was relative to the low-fit women, the high-fit women staved off dementia for nine extra years. Wow, nine extra years. That’s amazing. Is that the formula? Well, there’s not really a formula because they were high-fit and they didn’t really measure the exercise, but it suggested that exercise was helping their brain stave off dementia. And we have a clear idea why that might be. As we’ve been talking about, those growth factors that happen with regular exercise, make your brain big and fat and fluffy, would be able to stave off, theoretically, dementia. But that’s just a correlation. And correlation not equal causation. So maybe it is the high-fit women had better heart function. Maybe that was the key to staving off dementia. So maybe something about the circulatory system. Maybe that helped them sleep better. Maybe it was really the sleep and not the exercise. There’s lots of open questions there, but here’s what we do know, that you can start to reap significant brain benefits, not over 44 years, but over three months. And these are studies that I’ve done in my lab. We showed that low-fit people that exercise for just two to three times a week, 45 minutes cardio workout, they happened to be doing spinning, but anything that gets your heart rate up for 45 minutes would be equivalent. They got significant improvements in their baseline mood state, their prefrontal function got significantly better at baseline, not just right after exercise, and their hippocampal function got significantly better. So even if you are sedentary right now, that is doable. Two to three times a week of 45 minutes is what my studies have shown can significantly improve your brain function. But then what about the next group of people? I’m already working out. Am I doing enough? What is enough? And for that group of people, we looked at the effects of, exercise as much as you’d like for three months, more than you like, more than you’re exercising now for the next three months in a group of mid-fit people that were already exercising about two times a week, good cardio workouts for at least 45 minutes. And what we found was every additional drop of sweat counted. That is, the more you exercise above that, the more brain benefits you got in terms of better mood, better prefrontal function, and better hippocampal function. So not quite the exact formula, but we’re starting to work our way towards what we need to do to really reap those brain benefits of exercise. We’re really interested in asking, well, what changed in these people’s brains that we’re already working out? And I think that, first, this is a great moment to acknowledge that physical activity is doing so much. It’s changing, it’s improving your cardiovascular function, it’s improving the blood vessel, kind of, level, the physiology of your blood vessels. It is improving your oxygenation in your brain as well as this neurochemical bubble bath. So what I think is happening in that study that I, kind of, I summarized for you by saying every drop of sweat helps for your brain is that I think that those people are benefiting from even higher levels of baseline dopamine and serotonin. So you are just, kind of, keeping those dopamine serotonin levels higher for a longer period of time, better baseline mood. I think you are growing more hippocampal brain cells and strengthening the prefrontal cortex more than somebody that is sedentary, for example. And you’re kind of on a roll, you’re leveraging those changes, and you’re getting even more in. It’s all the same formula, but you get more, but every drop of sweat counts. And to ask the question that people might be thinking, can I exercise too much? And of course, everything comes on a U-shaped curve. So is too much chocolate bad for you? Yes. Yes, it is. Is too much exercise bad for your body and your brain? Absolutely, we can understand that in terms of stress on your body, but too much of anything is bad for your brain. Probably not most of us can get to that high enough exercise level. Maybe it’s those kind of obsessive athletes or Olympic-level athletes that really push their bodies to the limits. That might start to be negative for your brain. But most of us, and this is the good news, most of us have a really big window over which to improve our brain function through our physical activity. My greatest dream is still around this idea of optimizing exercise prescription, but it goes beyond exercise. I told you that exercise and meditation have similar effects on the brain. It’s really all those brain beneficial activities. And I would love to develop ways to start to identify those patterns of activities that are most beneficial for different populations. I happen to be dean of the College of Arts and Science. I have 9,000 students. What are the most beneficial things for college students that start off, you know, happy-go-lucky in September, but then it gets more and more and more stressful as the finals come up? What are those things that they can be doing, you know, to maximize their brain learning potential in the fall and decrease their stress, anxiety, decrease procrastination as the finals come up? And what about when you get out in the workforce? What can you do over different parts of your career, when you’re first starting out, when you’re mid-career, when you’re post-career, what are those brain beneficial activities that you should be bringing into your life? And of course, the ultimate question, which is one that fascinated me from the very beginning, what is that lifelong story, that trajectory of what we should be doing for our gender, for our age, for our ethnic group, for our genetic background that will make the aging process most beautiful for us? If I could answer that question, I would be golden. I just gave you, you know, the ultimate, these are all the questions that I’d like to answer. And I’ve learned in my research, you have to take advantage of the situation that you’re in right now. What tools do you have? Do I have lots of old people to test right now? No, I don’t. What I do have are lots of students that would benefit from all of this. So you can imagine that my question number one surrounds university students. And obviously, that is my number one goal as dean. I am very much responsible for their academic trajectory, but really, I consider myself responsible for their brain health. And so all of these ideas are kind of funneling in to that work that I’m doing.

– [Narrator] Chapter three: Are the neurological benefits of exercise overstated?

– Here’s that most skeptical question that I get about all the exercise work. And that is, “Well, Wendy, there’s all these correlations. They’re correlations, and they’re very, you know, optimistic. But when you go to the randomized control studies, a lot of those results are more subtle. They’re not, you know, that breathtaking. And maybe there are other things that are involved, like sleep, like cardiovascular function, like respiratory, you know, oxygen levels that don’t have nearly as much to do with exercise as you are saying. What do you say to that?” And I say, you’re absolutely right. The correlations are so optimistic, but they point us in a particular direction. And while I agree that some of the human experiments have more subtle effects, what I lean on in my continued optimism and my hypotheses about the transformative effects of exercise on the brain are the studies in animals that have shown true growth of hippocampal brain cells with exercise. They are so convincing because they show exactly how much the hippocampus grows with increased exercise, the longevity that comes with hippocampal function. In fact, my own advisor, as an undergraduate, looked at the effects of enriched environments on brain function. She created this enriched environment, kind of, scenario, which is kind of like, think of it like a Disney world of rat cages for rats. So you let rats live in Disney World with other rats and lots of toys to play with and different toys, and you compare their brains to rats that live in, kind of, a shoebox with maybe one other rat and no toys. Is there a difference? And this was the woman who defined brain plasticity, who kind of discovered adult brain plasticity. Her name was Professor Marian Diamond at UC Berkeley. And she showed that rats raised in those enriched environments, the actual outer covering of the brain got significantly thicker. And you know what experiment showed the biggest anatomical brain change with that enriched environment that we later know was coming from all the running around the rats were do doing in Disney World, it was pregnant mother rats being raised in these enriched environments. And then they looked at the babies that were born. Those babies whose mothers ran around the enriched environment, that Disney world of rat cages, their brains were the biggest compared to the offspring of mother rats that were raised in the shoebox. Those are the experiments that not only keep me optimistic, but create a real model about what is going on with the brain, with exercise, and how this could be a true tool to help us age beautifully into our golden years. Let me be clear, I welcome all this skepticism. It makes our experiments better. But what I would say is that we can all learn from each other and together kind of devise that perfect experiment so we know how much the cardiovascular changes are contributing to the brain functions that I’m interested in. We know how much sleep patterns are contributing to better cognitive functions that I’m measuring as well. All of this is fodder for what we’re all trying to do, which is really trying to understand what goes on here. And so yes, we still have a ways to go, but all of these factors are important when one is discussing something as complicated as physical activity. You might ask does, is there mutual skepticism around? And the answer is yes, because so many of the phenomenon that we, as scientists, study are complicated like exercise. And I don’t have time to learn all about cardiology. It took me all this time to learn enough about neuroscience, and we become so specialized that we can pick out, ooh, you should have been looking at that there. Well, you’re a cardiologist so you don’t know about that, but let me raise my hand and tell you about that. That is part of what comes out as skepticism and, you know, you should have known about all the cardiology studies that I did or my colleagues did. But again, it all kind of funnels into trying to really make sure that we’ve crossed all the Ts and dotted all the I’s in these very complicated phenomenon that we’re all trying to understand. What initially comes off as skepticism or criticism is absolutely kind of doable if one can come together across fields. That is one of the most difficult things to do, both within an institution or across institutions. But it is kind of the direction that science is taking multidisciplinary, really trying to see all perspective. Neuroscience as a field is one of the most multidisciplinary there is. It goes from molecular biology to behavior, and we all try and understand, you know, aspects of it, but cardiology doesn’t come in there. Bone science doesn’t come in there, but all of them may have insight to doing that. I mean, it comes down to it’s too easy to get caught up in the neuroscience and just looking at it from that perspective, even if it has multifaceted elements to the neuroscience perspective. But that is the future of science, is completely integrated for the whole body and for science in general. And it’s a hard question to ask, but that’s one that many institutions, including my own, NYU, is trying to address.

– [Narrator] Chapter four: Exploring the neurological effects of anxiety.

– It’s great to start with a simple definition of anxiety. So anxiety is the feeling of fear or worry, typically associated with situations of uncertainty. So it makes perfect sense why our global levels of anxiety have gone up over the last 2 1/2, 3 years. With a global pandemic, nobody knew how to deal with this, a brand new, very, very scary, uncertain situation, but, kind of, reel it back into everyday life. Obviously, it pops up with lots of uncertain situations that many of us deal with every single day. But it’s important to realize that this human emotion, anxiety, this normal human emotion, anxiety, exists on a really, really, really wide spectrum. It goes from everyday anxiety that can be from, you know, mildly annoying to, kind of, kind of, really, really annoying and really a drain on you, but then it goes all the way up to clinical levels of anxiety. That becomes a different beast. That becomes something that you must go see a medical professional to deal with. All of the techniques and the neuroscience that I talk about in my book, “Good Anxiety,” were really written for everyday anxiety. Now, that doesn’t mean that somebody with clinical anxiety can’t use those techniques. It’s just not the only thing that one should use if you have clinical anxiety. You should absolutely go see a medical professional. But I just wanted to make that clarification because there is a difference, and all of the approaches that I’m talking about are really for those of us, just everybody that has everyday anxiety. One thing that trips, essentially, all of us up is something called the negativity bias, which says that we are more prone to see the negative sides of things than the positive side. Why? It’s a safety mechanism. You wanna be extra careful if you are going to be, you know, in a dangerous situation rather than saying, “Oh, I’m gonna be just fine.” And so it is a protective evolutionary safety mechanism. But what happens is, if you’re tired, if you’re stressed, if lots of problems are coming up, you will tend to see the world, “Oh my God, they hate me, this person hates me,” “I’m never gonna get the job,” “I’m never going to lose the weight that I wanna lose.” All these things come up as part of that negativity bias, and that becomes part of the, what I like to call the big, kind of, stone of anxiety that you wear around your neck every day, kind of dragging it along with you. Part of that is the negativity bias. There are many, many different brain areas that get activated with anxiety, but simplistically, there’s one that we know that is particularly activated in the similar emotions of fear and anxiety. And that is a brain structure called the amygdala. The amygdala is one that is kind of automatically activated when there is a possibility, you hear that, you know, that bump in the night that launches your anxiety, and the brain area that could help that calming that might happen in that situation is the prefrontal cortex, the area that’s involved in executive function. It helps you kind of order your day, but unfortunately, in situations of high stress, high anxiety, what happens is not only is your amygdala activated, but your prefrontal cortex get shut down too. So that makes the situation even worse. And so that’s part of what can happen when, you know, one can kind of devolve into a really serious situation or a case of anxiety. Brain plasticity is the brain’s extraordinary ability to change and rewire itself in response to the external environment. And probably the most common form of brain plasticity that you’ve done today, I’ve done today already, is new learning. Every time you learn something new, there’s a change in my favorite brain structure, the hippocampus, that, you know, allows for the laying down of that new memory. This is something we’re doing all the time, every day, but I’ve, in my work, tried to use and explore the boundaries of brain plasticity to address some very challenging issues that have come into the society, particularly our high anxiety levels. I use brain plasticity as the core of my entire research program. Memory, I started out studying memory as a form of brain plasticity. The effects of exercise on the brain, exercise is one of the best examples of positive brain plasticity. But when I started getting into anxiety, I realized how critical brain plasticity was to address anxiety, because one of the first things that I wanted to do was flip the script on our whole mindset around anxiety. You hear the word anxiety, you think, “Oh, God, that’s the thing I wanna kick out the door. It’s a disease. I have it. I don’t know how to get rid of it.” But here’s the flip that is dependent on our ability to have brain plasticity, our ability to learn, basically. And that is that anxiety is a normal human emotion. We all have it, okay? So you’re never gonna get rid of it, and we all have it because it is protective. It evolved to protect us. And so my whole book, “Good Anxiety,” is teaching us to look at anxiety in a different way to really flip the script on anxiety and use neuroscience and tools from psychology as well to learn how to take advantage of anxiety and learn about the gifts or superpowers that come from it. When I started writing this book, “Good Anxiety,” it was because I noticed in my students and my friends, my colleagues, myself, higher levels of anxiety. And this was well before the pandemic started. And so I started to write about what I knew about neuroscience and psychology that could really help us understand and address anxiety. But in the middle of writing the book, there was something that happened that completely changed the book for me and changed my attitude towards anxiety. And it included anxiety, but it was really a really situation of grief and something that all of us unfortunately have to go through. In the period of three months, I lost my father and my younger brother, both of heart attacks. And I can tell you it was one of the most difficult times I’ve ever gone through in my whole life. And so it was impossible to write my book about anxiety. I put it on the side. I had to deal with all these feelings of grief, of sadness, of anxiety. Am I gonna feel better? And it was rough, and it took a while to come back. I used all the tools that I knew. I exercised, got myself into exercise, I reached out to my friends, I did my regular meditation. And I remember one day I was doing a video exercise, which is what I do every day, and I hadn’t seen this video before, but the trainer that day said something that helped me so much, and that was, in the context of physical activity, she said, “With great pain comes great wisdom.” And I thought, “Oh my God, that is what’s coming from the great pain of the grief, including anxiety mixed in, that I’d gone through.” What is the great wisdom? The great wisdom that underlined that, that it was so painful and so cute because there was so much love behind that emotion. And I thought, that is the thought and the intention that I need to help me get out, finish my emergence from this grief. What’s behind that was so much love. And that, you know, it’s the flip side of love, which is this great grief if your loved ones pass away. And that was so helpful for me at this moment. And then I realized it was transforming the way that I was thinking about this anxiety book because if that terrible emotion, negative, horrible emotion of grief had this silver lining of wisdom, what about anxiety? Could anxiety be helpful? And was my book just gonna be about techniques to reduce the big, bad anxiety? Or was I going to approach it as something that could be beneficial? That’s when the book changed for me. It became a quest. I needed something to put my mind on, and I dove into trying to find gifts or superpowers or beneficial elements from all the different kinds of anxiety that I read about, that I experienced that I was writing about already. And that’s how I came up with the six gifts or superpowers of anxiety. They would not have come to light if I didn’t go through this experience in the middle of writing this book. But it shifted the way that I thought about anxiety. It shifted the way that I was able to recover from this. And it shifted my thoughts about human emotion in general. In “Good Anxiety,” I talk about six superpowers, but let me mention my top three. The first one is a superpower of productivity. Did you realize that your own form of anxiety could be a superpower of productivity? And it works like this. It focuses on one of the most common forms of anxiety that we all suffer from. I certainly suffer from it myself, which is that what-if list. What if you didn’t do that? Or what if you did that and you didn’t do it right? And for me, it hits me right before I’m gonna go to sleep, and it disrupts my sleep. So what do you do? That is your anxiety welling up. And so here is the trick, that anxiety is focused on things that are important to you in life. That is the key. You don’t get up in the middle of the night, worrying, “Oh my God, I didn’t finish that last episode of the Netflix series I’m watching,” right? It’s about the project you’re working on or about a really important relationship. So these are things that are important to you. And so the way to transform it is to turn that what-if list into a to-do list. Take each one of them and do an action, you know, put an action on each one of them, whether it’s asking a friend for help, doing something, Googling something, and go tick through them one by one. How does that help? It helps because evolutionarily, anxiety evolved to have us put an action on it. Typically, 2.5 million years ago, it was either you fight the danger that was causing anxiety or you run away from it. That is the fight-or-flight response. And so you can help alleviate that form of anxiety by putting an action on it, even if it is, I’m gonna ask a friend, I’m going to spend 30 minutes of detailed work on this thing that I’m worried about. That is how you get productivity from your anxiety, and that is superpower number one. Superpower number two is the superpower of flow. And this one, I’m very proud of because all the data out there says that anxiety can eliminate flow. So flow is a psychological state. I like to think about it as, it’s those moments that you’re doing something that you’re really good at, and it’s really exceptional. Time stands still. You know, it’s like you’re moving in slow motion, and everything is just going beautifully. And I always think, I’m a student of the cello, I always think of Yo-Yo Ma who was playing the Bach’s solo “Cello Suites.” You know, not every single time, but that one time at Carnegie Hall, the sound was just so beautiful, he was in flow. And so I knew I wanted to talk about flow, but I couldn’t just say, “Well, sorry if you have anxiety, no flow for you.” And so I was experiencing writer’s block. I didn’t know how I was gonna bring this concept in without being very just depressing about it. And so to alleviate my writer’s block, I went to a yoga class. So I go to yoga class, I’m doing my up dog, my down dog, I flip the dog, I was doing really well. And then I get to the end of class, and I go into my favorite pose, which is, of course, Shavasana, laying down in Shavasana. And it hits me that I am flowing in Shavasana, that I am laying on the ground still better than anybody has laid down on the ground still, at least I feel like I’m flowing in Shavasana. Okay, and maybe it’s not classic flow. Maybe it’s micro-flow. And so I came up with this concept of micro-flow. And then I realized that my micro-flowing Shavasana was even sweeter. Why? Because I had writer’s block. I had that anxiety about what was gonna happen. I didn’t know. That uncertainty was coming in. And so I realized that your own anxiety can make your own moments of micro-flow, which we all have during the day, even if you don’t realize you do, make them even sweeter. And so it’s kind of a realization that your own anxieties, helping those moments of micro-flow be even, as I like to say, flowier. That’s superpower number two. Superpower number three that comes from your own anxiety is my favorite of all the superpowers. And it comes from my own evaluation of my own anxiety, my own history of anxiety. And I was a very, very shy young girl growing up. So, you know, hiding behind my mom’s legs. I was always interested in class, but always had this fear of asking questions in class. Why? For the same reason everybody’s afraid. You’re afraid you’re gonna say something stupid and you’re gonna look like an idiot in front of the whole class. So I had that fear all through my very, very long educational process. But I was interested in teaching and in academia. So one day, I find myself at the front of the classroom, and here’s what I realized. I didn’t realize it then, but I realized it later, that that lifelong anxiety of shyness and being afraid to ask in class gave me a superpower of teaching in that classroom, because I knew instinctually that there were maybe 10 times as many people that had questions that didn’t have the bravery to lift their hand up, but they were just having silent questions in their brain. So I always came early, stayed late, made sure that I had a moment of private time to answer questions for everybody. And so that became my superpower, but here’s how it works for everybody. Think about that anxiety that is most familiar to you, your most common form of anxiety. You know what it feels like. You know what it looks like. All you have to do is turn that anxiety to the outside and notice when others might be suffering from that same form of anxiety. And here’s your superpower. All you have to do is give a kind word, a simple helping hand in that situation. That becomes your own superpower of anxiety that’s based on your own form of anxiety. And I love this superpower because I can’t think of anything that we need more in the world today than higher levels of empathy. Cognitive flexibility is the idea that we are able to look at and approach situations in lots of different ways. We are also habit-forming animals. And sometimes without even knowing it, you are approaching the same situation, the one situation the same way that you approached it when you were, you know, six years old. Cognitive flexibility says that if there is a realization, there are other ways to approach it. You have the ability to do just that. An important concept that people often wanna build up more in themselves is this idea of resilience. Can I withstand difficult situations and come out stronger or just as good as before that situation happened? It is such an important skill to build up. And one of my favorite experiments to address this was an experiment done in animal model systems. And they compared two maybe very familiar sounding situations. They raised young animals, these were young rats, in situations where they never had a care in the world. One set of rats, no stress, all the food, all the care, no problems at all, all the water, great place to live for all of their life. Another group of rats, young rats, were exposed to mild difficulty all through their growing up. Some, you know, not terrible, you know, stresses, but mild stresses regularly. And then at some point in time when they became just young adults, these rats were exposed to a very difficult situation. They had to swim in water, and they had to swim for a long time to really get through it, what happened? Well, those rats that grew up with no stress at all, they had a very, very difficult time. Their adrenaline levels, their stress hormones really spiked up. They had a long time to recover, but those other rats that had intermediate, intermittent mild stress, they came out of it like, “Ah, that’s fine. Give me a little stress. I’m just fine.” And so you think about this, think about this in your own life. Part of the learning, part of that silver lining that comes from even the most difficult situations is the psychological knowledge that you could come out of it, that you got through it, that your, you know, your body got through it. And maybe it’ll come up again. Well, you know that you can come through it. That is the core of how one can kind of build up more resilience in one’s own life. It’s absolutely clear that there’s a wide range of, kind of, personality types. Some that are less prone to anxiety, some that might be more prone to anxiety. Again, understanding that we all have certain level of anxieties. It is a normal human emotion. And so I come back to this idea of brain plasticity, that we are all capable of learning. Now, if I take opera lessons, will I become Maria Callas? No, I will not. But will I improve my vocal range better than I am today? Yes, I will. And I apply that to resilience and dealing with anxiety at the same time. There are systematic ways that you can approach it, learn how you approach it best, get help from the outside. And systematic, intentional attempts to build up your positive coping mechanisms will benefit you in the long run. There’s always gonna be a tug of war, a push and pull between your resilience, your negativity bias, your anxiety levels, your happiness levels, and it’s all at play because all of that is part of our, kind of, normal kaleidoscope of human emotions. And again, something that is comforting to me, hopefully it’ll be comforting to you, is that all of these more difficult or uncomfortable emotions, anxiety, sadness, worry, all of them are normal. And again, they are there to protect us. They’re there to warn us about different things. And if I was happy all the time, then it wouldn’t be happy anymore. It would be just normal. Those difficult emotions lift up what we call happy right now, but they are also there for warning. If I didn’t get scared for certain situations, I would just walk in with, you know, eyes wide open to a really, really dangerous situation. They’re there to protect us, and that really gives me comfort. And now, that doesn’t necessarily help somebody that has really, you know, high levels of responsiveness to sadness or worry or fear. And that’s where, little by little, you can build up and you can learn to respond to it, build up your positive coping mechanisms to help and counteract those situations of sadness or anxiety. I talk about, in my book, over 40 different tools to decrease anxiety that everybody can use today. They’re simple, they’re not gonna cost you thousands of dollars. There are things that you can try in your everyday life, and they’re very powerful. It’s absolutely normal that your level of resilience might go up and then slide back and go up again and slide back. It all depends on the level of stress that you’re dealing with. And sometimes you really can kick it in the butt, and other times you’re not, you know, you need time to recover. That is absolutely normal. But again, all of that is building up your overall resilience. You know, if it doesn’t kill you, it makes you stronger. I love that saying because I think it’s absolutely true, absolutely true for your resilience. It’s not about whether you have it or not. It’s just about, you know, recovering from it. You’re gonna get stronger and stronger. Your resilience is getting stronger and stronger as you deal with all of the stresses in life. That’s how I think about it. One of the things that everybody does, including myself, when dealing with anxiety is everybody has coping mechanisms. You have positive ones and negative ones. And how do I define positive versus negative? Well, kind of, beneficial is positive and less beneficial, maybe in the moment, but less overall beneficial are those negative coping mechanisms. What are they? Alcohol, drugs, kind of, smoking, those kinds of things that could give you immediate relief, perhaps, from your anxiety, but not good for the long-term. Positive coping mechanisms I talk about in the book include things like, we’ve already talked about, the positive effects of exercise on anxiety, on meditation, but one that is so powerful is this idea of having an activist mindset. What is that? An activist mindset is one that is flexible, that can look at a situation and see lots of different possibilities. Everything from that negativity bias that says, “Oh my God, this is gonna be terrible,” all the way to, “Oh, actually, maybe this is gonna teach me something really interesting, really new.” Now, this is a really important part of my book, this idea of a activist mindset. And I think it was emphasized because of this situation that really shaped the book “Good Anxiety,” which is the difficult passing of two of my family members and really coming out of that with a beautiful example of an activist mindset. Everybody’s going to experience loss of a loved one during their lifetime. Most everybody will. And my activist mindset was knowing that all of that pain and that loss and that sadness was undergirded by love for these people. And that was my activist mindset. And I brought that beautiful, helpful, kind of, almost lifesaving example of activist mindset to my addressing anxiety. And what is it about my anxiety, my particular form of anxiety that is difficult? Can I bring a superpower or a gift from that? And that is, again, the core of the book. And what I try and do in my own life, and what I describe throughout the book is really bringing a new perspective, new ways to look at, new science-based ways to look at anxiety as an opportunity to learn, to grow, and to learn more about yourself. To have an activist mindset, to be able to look at a situation and see multiple different ways that you could approach it requires something called cognitive flexibility. It requires that you’re not gonna do the same kind of response, have the same response patterns as you’ve had for perhaps many years, perhaps your lifetime, but you’re gonna try something new. Sometimes it’s hard. Sometimes it’s challenging. But if you practice it in different ways and every single day, it can be something that becomes a very powerful tool. And the way that you could, kind of, approach it that I do, I find it motivating, is before you actually try it on yourself, that’s the hard part, think about the people that you admire that approach things in a particular way, leaders in your work, the leaders of your family, and the way that they handle family disputes, bosses that handle conflict situations in a beautiful way. Maybe that’s not the way that you are handling situations, but you can use an activist mindset to first identify a role model and then use your own cognitive flexibility to bring that same behavior into the situation where you’re the one trying to, kind of, diffuse a situation or convince somebody to do something in a particular way. That is a wonderful way in. It allows you to appreciate, kind of, the friends, work friends, relationships that are already in your life and gives you a wonderful, kind of, roadmap to head towards as you practice your activist mindset.