the left dorsolateral prefrontal cortex is the area of the brain that actually has some control over and especially can interpret what's going on in this ACC region. Now, most of you probably haven't heard of the ACC, most of you probably have heard of a brain area called the amygdala, it's an almond shaped structure on the two sides of the brain, people talk about the fear center, etc. But your ACC, the inter cingulate cortex gets input from areas like the amygdala, your threat detection centers, but it also gets input from an enormous number of other areas of your brain and body, including your heart, your gut, so it gets information about how full that is distended, or how empty your gut is, it gets information about how quickly you're breathing from input from your lungs, and related structures. It's an absolutely critical station for making sense of what's going on in your body. And it works very closely along with one other structure and promises is going to be the third structure in this triad. And then I'll stop listing off names. So we have dorsolateral, prefrontal cortex, think of that as sort of the interpreter of what's going on inside of you. You have the ACC, or anterior cingulate cortex, which is the area of your brain that's bringing in all this information about what's going on inside your body. And he'd been on the surface of your body, you know, if you have any pain or an extra mosquito bite on the surface of your body, your ACC would definitely register that. And then there's this other absolutely incredible brain structure, which is called the insula, i en su la insula, the insula has a bunch of different parts to it. But the insula is another area, that is interpreting signals of what's going on in your brain and body. So the ACC, and the insula are working together to try and figure out what's going on inside me. And in addition to that, the insula is interpreting information about what's going on outside of you. So your insula is saying, for instance, this is a steep hill that I'm running up. And as a consequence, whatever heart rate increase that I'm experiencing your heavy breathing or burning in my lungs, this all makes sense. I don't have to be worried I don't have to be scared, I might want to slow down. But this makes sense. Whereas it for instance, in the example I previously gave, where if you're sitting in a room, and everything is pretty calm, and all of a sudden, you start feeling really uncomfortable, like your stomach doesn't feel right, or you start breathing quickly, you start having a so called anxiety or panic attack. In large part, that's because the shift in your bodily sensations doesn't match or doesn't correspond to something in the outside world. So there's this incredible triad, which includes the left dorsolateral, prefrontal cortex, the cingulate, or anterior cingulate cortex, and the insula. And those three are working together in a kind of conversation. It's a neural conversation, but a conversation nonetheless, trying to figure out, Okay, what's going on inside me? How do I feel? What am I thinking about? And this could be thoughts about the past, or the future or the present. They are also in a conversation as to whether or not the sensations that you're experiencing meaning how quick your breathing is, or how slow your breathing is, how your heart feels, how your skin feels, any sensations of pain or pleasure, for that matter, whether or not that makes sense for the situation you're in and trying to determine whether or not you are doing the right things as a consequence of those sensations. Okay. So, again, if you can't remember the names of these different neural structures in the brain, don't worry about it, it's really not that critical. what is critical is that you understand that there's a conversation that's constantly occurring, as long as you are awake, trying to figure out what's going on inside of you whether or not it makes sense relative to what's going on, outside and around you. Now, humans are smart, that is we are, to some extent, conscious of the fact that we have memories of the past, awareness of the present, and anticipation of the future. So we do realize, for instance, that we can be sitting seated at the dinner table, excuse me, and have a thought about something tomorrow, maybe an exam that's stressing us out or something like that. And that will change our bodily state in a way that is not optimal for what we're doing in the moment. But that can still make sense to us. Because that exam is important. Maybe we're feeling some pressure about a hard conversation we have to have or maybe we are very excited about the next day, and we can't eat because we're so excited. And that can make perfect sense to us because we do have access to this knowledge about self that we can think about the past the present or the future. So that makes the conversation these three structures are in even more interesting and dynamic because what it means is that we can be doing something II eating, talking, running any number of different activities, and our bodily state may or may not match what we are doing in a way that's adaptive for that. And yet that can be completely okay or at least understandable for us. Now, a major emphasis of a meditation practice is to make us so called more mindful. What is mindfulness? Well, again, there isn't one perfect, universally accepted, operational definition of mindfulness. That's basically nerd speak for saying people can't agree exactly what mindfulness should be is, and means for everyone. But most people assume and I think, agree that mindfulness includes something about being present. And when I say present, that doesn't necessarily mean present to one's surroundings. Because of course, a lot of meditation practices that are designed to make us more mindful and present, are designed to make us more mindful and present to what's happening internally while ignoring everything that's happening externally. But they are designed to make us more present to our bodily sensations, and in particular, our breathing and our thoughts in the moment. So let's now explore what a generic meditation practice looks like. And let's evaluate how that tends to change the activity of these neural circuits in the brain and body. And then from there, we can split the conversation into a couple of different bins. That is meditation practices that are ideal for enhancing focus, meditation practices that are ideal for improving mood meditation practices that are ideal for improving sleep, and meditation practices that believe it or not benefit all of those things in one fell swoop. Okay, so what happens during a meditation practice at the neural level? In order to answer that question, we are going to be scientists, that means you and I are going to be scientists. Now, we are going to break down a practice into its different component parts, and address what we know for sure about the brain activation states that occur with those different component parts. In order to do that, let's use a somewhat generic form of meditation. But it's generic and pretty far reaching because I would say that, for most people, about 75%, let's say, a meditation practice is going to involve stopping meaning getting out of motion, sitting or lying down. And in most cases, closing one's eyes. Although it is absolutely not required to close one's eyes. During meditation, there are many forms of meditation that are done eyes open. But for most people, it's going to involve stopping our movement that is not ambulating not walking or running. So see, seated or lying down, with eyes closed. When we do that, meaning when we sit or lie down and close our eyes, as trivial as that shift might sound to you, it actually is a profound shift in the way that your brain and other neural circuits in your body function. For the following reason. When we close our eyes, we shut down a major avenue of what's called external perception. What do I mean by external perception? Well, very briefly, we are sensing things on our body and in our body all the time, we are also sensing things from outside of us all the time. So these can be sights or sounds, touch on our body sensations with inside our body, etc. Now, sensation is distinct from what we call perception. Perception is put simply the sensations that we happen to be paying attention to. So at any given moment, you are sensing many, many things, there are sound waves hitting your ears, there are pressure receptors on the bottoms of your feet, sensing your shoes, or your sandals or the floor, etc. But you're not perceiving them until you place your attention on them. Now, the way perception works is that you have so called spotlights of attention, you can't perceive everything all at once every sound, every sight, every touch, that will be overwhelming. In fact, that would be terrible. Rather, you have spotlights of perception that can either be very narrow. So for instance, you could focus all of your perception right now on your big toe of your right foot. And really pour all of your awareness, your attention into what you're perceiving there, what it feels like if there's tingling or pressure, heat or cold, etc. Or you can broaden that spotlight to include both feet or all your toes on both feet, and then your legs and your whole body or the entire room. Perception is like a spotlight. And I should mention, there are very good data that we can split our attention into two but probably not more than two spotlights. And we can make those spotlights of perception, either very broad and diffuse or very narrow. You can practice this now if you like you can pick a spot on the wall away from you anywhere. Or if you're driving, you can look at some location and you can focus intensely on one small location. For instance, a tree in the horizon or a person on the street or any number of different things outside Have you or you can broaden that spotlight to include the entire scene at once. You can also focus a spotlight of perception on your body, say on the left upper portion of your chest. And of course, you can focus on the left upper portion of your chest and something outside of you can split your attention between those two perceptual spotlights. It's very hard, although not impossible to have three perceptual spotlights. But most people can split to two points of attention or perception pretty easily. The other thing that most people can do pretty easily is merge those two spotlights, or rather to have just one spotlight of attention, so you don't always have to have two spotlights of attention on and here I'm using the word attention and perception interchangeably. But you could, for instance, have two points of attention. So you're talking to somebody and you're paying attention to whether or not somebody's walking in the door or not. So that's two, or you could be completely focused on the person you're talking to. Or you could be completely focused on the stomachache, or the great sensation of hunger that you have in your belly while talking to somebody, in fact, you're not even listening to what they're saying at all. Okay, so you have two spotlights of perception, you can split them or merge them into one. And this is very important, those spotlights of perception can intensify or dim. And there I'm using analogy, what I mean by that is, your perception of what's happening within those spotlights can be very, very high acuity that is you can register very fine changes in detail like tingling on one side of your big toe of your right foot versus the other, or it can be somewhat more diffuse, you're just thinking about your whole toe, which in that case, seems like a small area. But the point is that you can consciously adjust the acuity. That is the fineness of your perception, all of this is under your power, because of the incredible ability of a brain structure, whose name you now understand. And no, which is the left dorsolateral prefrontal cortex, although there are other areas of your brain involved as well, your ability to direct your attention to specific things in your environment, or within your body or to split those points of attention or merge them or dial up the intensity of how closely you're paying attention to every little shift or ripple, and change in sensation there. Or to kind of dissociate, if you will, for lack of a better word to disengage from that perception. All of that is under control, because of your ability to engage this area that we call the prefrontal cortex and in particular, the left dorsolateral prefrontal cortex, I'd like to take a quick break and acknowledge one of our sponsors, athletic greens, athletic greens, now called ag one 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 to be the probiotics that I need for gut health. Our gut is very important. It's populated by 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 and 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 athletic greens.com/ubermann. 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 and the car on the plane, etc. And they'll give you a year supply of vitamin d3 k two, again, that's athletic greens.com/ubermann to get the five free travel packs and the year supply of vitamin d3 que tu Okay, so now if we look at the example of what happens when you sit or lie down and close your eyes and decide to meditate, you should immediately realize that that's a tremendous shift in your perceptual ability. Why? Because that spotlight of attention, while it can be oriented toward, for instance, what you hear in the room, or maybe the feeling of wind, moving trees in the environment that you happen to be in. When we close our eyes, we shut down one of the major avenues for sensory input, which is vision. And when we do that, there's a tendency for those perceptual spotlights to be focused more so on what happens at the level of the surface of our skin, and inside of our bodies. And that informs us about something very important, which is that there are actually two axes or two ends of a continuum of perception. Up until now I've been talking about perception and intention is kind of the same thing. And indeed they are at least for sake of this conversation. But within that word perception, or within that word attention. There's a continuum. And that continuum has on one end, something called interoception interoception, spelled with an eye is everything that we sense at the level of our skin and inward So the sensation inside our stomach, the sensation of our heart beating, some people can sense their heart beating pretty easily other people have more challenge doing that. What we are feeling on the surface of our skin, how hot or cold we feel that's interoception. In contrast, at the other end of the continuum is so called external perception spelled with an E, extra perception is perception of everything that's outside or beyond the confines of our skin. So by shutting our eyes, and in particular, in a meditative practice, where we direct our attention toward our so called Third Eye Center, this area right behind our forehead, which, not coincidentally, is the prefrontal cortex, or in some cases where people will focus on their breathing, so the movement of their stomach or the movement of their diaphragm, or the lifting of their chest, or the extension of their belly while they breathe. By doing that, we are taking what ordinarily is a perceptual state that's split between the outside world external perception, and usually also toward our interstate, you know, most people are generally in touch with how they are feeling from the skin inward, while they are also paying attention to what's outside of them. You can think about somebody, for instance, at a restaurant or sandwich shop about to order a sandwich and you're reading in the menu. So that's external reception, right? The menu is outside the confines of your skin. And little ideas, or maybe big ideas come to mind about what the roast beef sandwich or the vegetarian sandwich will taste like, what it will do for you what, what's in it, what you like, what you don't like, etc, that's splitting interoception and an extra reception. But when we close our eyes, we stop, we slow down, we focus on our breathing, or that Third Eye Center, the majority of our perception then shifts to interoception. And when we shift down to that end of the continuum of, of interoception, something very important happens. What happens is that those two regions, the ACC, the inter cingulate cortex, and the insula, really ramp up their levels of neural activity. And that should make perfect sense to you, because those are areas of your brain that are registering and paying attention to the various sensations of how full or empty your stomach feels. Whether or not the surface of your skin feels hot, or cold, and on and on. So by just sitting down or lying down and closing your eyes, your brain undergoes a massive shift from external reception to interoception. Now, that's not to say you can't be distracted by external events, and in fact, many people are, but the early stages of transitioning into a meditative state, involve this shift down the continuum, or I should say to one end of the continuum, because there's no down up there's just the Continuum Shift along the continuum to heightened levels of interoception. Now, I mentioned this briefly before, but many people are very interoceptive. Ly aware, just naturally, even if they don't do a meditation practice, other people are not. And there's a pretty good measure of whether or not you have high levels of interoceptive awareness or capability. And that is your ability to count your heartbeats without placing your fingers anywhere with any pressure to take your pulse. You can do this if you like, you can actually try and estimate your number of heartbeats simply by trying to feel your heartbeat. Some people are very good mean they're very accurate at doing this other people are not, it does seem to be an ability that can be trained up quite a bit. And in fact, meditative practices will improve your interoceptive awareness. But and this is a very important point, heightened levels of interoceptive awareness, while that might sound attractive, oh, but to be really in touch with your body. That is not always beneficial. Why? Because many people who for instance, have excessive levels of anxiety, have excessive levels of anxiety, because they are very keenly aware of any subtle shift in their heart rate or breathing, or change in their, the sensations within their stomach. Whereas other people were less aware of their bodily state, that can be beneficial, right? It can be adaptive or not, depending on the circumstances, it's probably not adaptive, to be very, very aware of your internal state. If, for instance, you're doing public speaking, you don't want to be thinking about what's going on in your stomach or how quickly you're breathing. I'm certainly trying to ignore all those signals those sensations now. But for somebody who has no awareness of what's going on very little interoceptive awareness, that can be problematic, too, because these are the very people who can ignore the fact that they're having a heart attack or can ignore the fact that they have high blood pressure, and are carrying about life focused on everything external with no awareness of their own body, their quote, unquote, out of touch with their body. So we want to be very careful about placing valence, which is a sort of value of good or bad on interoceptive awareness versus extra receptive awareness. More importantly, we want to emphasize that when you undergo a meditation practice, if it's of the sort where you stop your movement and close your eyes, you are training for interoceptive awareness, this becomes input And later, we get into discussions about meditation for reducing anxiety, some people may opt, in fact, I would say some people ought to opt for a meditative practice, which involves more external receptive awareness, actually a meditation like a walking meditation, or even a seated meditation, where they are bringing their focus to a place outside their body, as opposed to inside their body. And in fact, there are examples of people who have meditated quite a lot who develop such a heightened state or awareness of their interoceptive components that is just fancy again, nerd speak for so aware of their breathing and of their heart and of their, the state of their gut, that it actually is intrusive for daily activities. So I will ask you to ask this question of yourself now. Are you somebody who tends to be very in touch with your bodily sensations? So for instance, from the skin inwards? Or are you somebody who tends to be less in touch with or aware of your interoceptive? State? There is no right or wrong answer, you don't get an A or an F or a D or a C, depending on your answer. It's just a good question for each and every one of us to answer. And I think most people will answer that. It depends. It depends on whether or not you are in a social setting, or whether or not you're alone. But we are going to return to that answer. So keep it in mind, because it will become very beneficial in building an optimal meditation practice for you. But for now, just know there's this continuum of perception interoception, and extra reception closing your eyes increases interoception opening your eyes dramatically increases external perception just automatically, just automatically, because so much of your brain, in fact, 40% or more is dedicated to vision. And this I should say, for those of you that are low vision or no vision, then those of you that are blind or have poor vision, this entire process is translated to the auditory to the sound domain. So it's true for people that can see that's true for people that can't see, of course, people that can't see closing the eyes doesn't have this huge shift towards interoception. But there have been a few studies, not as many as I would have liked to find. But a few studies have, for instance, people who are blind or have low vision don't see very well. And when they close their ears, and they can't hear the external world, or they put headphones on or noise cancelling headphones, then the world inside of them becomes very prominent relative to the world outside of them for obvious reasons. So I asked you to ask yourself whether or not you are somebody who tends to be more interoceptive Lee aware, or not more ex terror receptively aware or not? And some of you might not be able to answer that question. And if you can't, chances are, that you are effectively sliding along that continuum, depending on the activities that you're doing. So you're probably the kind of person where somebody comes over to you and starts talking to you, you will engage in that conversation, and you don't feel so inside your body that you're thinking about your heart beating and whether or not you're flushing, read, etc, you're going to pay attention to what they say. Many people however, when somebody talks to them, if they have social anxiety, or even a slight bit of social anxiety, we'll be thinking about whether or not their cheeks are flushing or whether or not they look right or sound right or whether or not they have something in their teeth. These are normal responses. But they really speak to this issue of whether or not you tend to shift more towards interoceptive awareness or extra receptive awareness. And of course, it's context dependent, it will depend on whether or not you're, you know out on a date with somebody that you know, you would Lowe's to find out later that you had food in your in your teeth, or whether or not you're with somebody you're more familiar with where that would not really matter much or the other person would tell you this kind of thing. What does it mean to be at one location or another location along this continuum of interoception or extra perception? Well, we know what it means neurally, right. We know that if you are more interoceptive ly aware, your insulin ACC are active. But that's not very useful. That's not That's not helpful as a tool. That's just a fact. Now, there have actually been studies of what a meditation practice can do in terms of moving you along this continuum from where you naturally sit, in order to help you function not just during the meditation, but at all times. And in order to illustrate this, I want to start with a description of what is now a classic study. It's a very cool study has a very cool name, and talks about something very important that will come up again and again, in today's conversation. That's something called the default mode network. The default mode network is a collection of different brain areas that essentially are active when we're not doing much of anything, and certainly is active when we are not focused on one particular task or conversation or activity. The default mode network can be thought of more or less as the network that generates mind wandering, or our thoughts drifting from the past to the present to the future. Remember earlier I talked about how your perceptual spotlight can either be two spotlights or they can merge. Well, similarly, human beings can think about the past, surely the present, definitely, and the future. And it turns out we can also split our thoughts. Just like we can split our perception And into two of those three things. So I can think about the past a past event. And I can think about the present, I can split my thinking and my memory in that way, I can also think about the present and the future, I can also think about the future and the past, although it's very difficult, although not impossible to split one's thinking and memory into the past, the present and future simultaneously, not easily done, but pretty easy to split one's attention and thinking into two of those three things, either the past the present, and the future, or any two of those three things. Okay, just like with attentional spotlighting, you can place your mind you're thinking in your memory, your cognition, onto one of those things that be very, very present, or the past, in the present, and so on, and so forth. The default mode network, while it involves a lot of different brain areas, can be thought of simply as the network of brain areas that are active when your mind is wandering between these different time domains. And the paper I'd like to share with you, as I mentioned before, is now a classic paper has a wonderful title, which is a wandering mind is an unhappy mind. Now that sounds almost like a news article, or a news article about a scientific paper. But that's actually the title of the scientific paper, which was published in the journal Science, which is one of the three Apex journals. You know, scientific publishing is competitive, but it's especially competitive to get manuscripts accepted into science into nature and into the journal Cell. So it represents kind of the one of the Super Bowl NBA championships and Stanley Cup, if you will, for us sports aficionados of scientific publishing, this is a paper from Matthew Killingsworth. And Dan Gilbert. It was published in 2010. But it's still considered a classic. And this paper, a wandering mind is an unhappy mind has a number of very important points, I'm going to paraphrase certain elements of it for you, because they say essentially, what I would like you to know, far better than I could. And I could say, so first of all, they started out with a statement, which I confess I disagree with, which is, unlike other animals, human beings spend a lot of time thinking about what is not going on around them. Contemplating events that happened in the past might happen in the future, or will never happen at all. I agree with their assertion that human beings do that. That's certainly my experience. Although I must say, I don't think there's any evidence whatsoever that other animals don't do it also. So my apologies, Killingsworth and Gilbert, but I'd be happy to go toe to toe with you on that I am not aware of any data that proves one way or the other what other animals are thinking. So let's set aside other animals. And let's focus on the human animal. Now, their point is still a very good one, which is that humans have this wandering of the mind that they call stimulus independent thought that is, there's nothing happening to create these thoughts, or anything happening in the immediate environment. These thoughts are just happening on their own internally, that's the default mode network. This study was important. In fact, it was a landmark study, because they did it right about the time that smartphones became a widely available and in use. So again, 2010. So they basically pinged people, they contacted people on their iPhones