Transcript for: Exploring the Science of Meditation
Welcome to the Huberman Lab podcast where we discuss science
and science-based tools for everyday life. [MUSIC PLAYING] I'm Andrew Huberman, and I'm a professor of
neurobiology and ophthalmology at Stanford School of Medicine. Today, we are discussing meditation. We are going to discuss
the science of meditation, that is, what happens
in the brain and body while we are meditating, and we will talk about
the science of meditation as it relates to how the
brain and body change as a consequence of meditation, that is, what you export or
take from a meditation practice that can impact everything
from your sleep to your mood. For instance, meditation has been shown to alleviate symptoms of depression. And we will also talk about how meditation can be used to enhance focus
and other states of mind that are useful for work
and other aspects of life. Now, of course, most of you have probably heard of meditation, and when we think of meditation, most often, we think of somebody either sitting or lying down. If they're sitting, we might imagine them in the so-called lotus position, you know, sitting with
legs crossed, very upright, with hands on the knees or,
you know, crossed in our lap or something of that sort. Typically, we think of somebody
who is in a very calm state, eyes closed, focused on their
so-called third eye center. The third eye center is the
area just behind one's forehead. There's no third eye there,
at least there shouldn't be, but I'll tell you why it's
called the third eye center and what the origins of that are and why it's relevant, actually,
for a meditative practice. With all that said, it
turns out that meditation encompasses a huge variety
of different practices. Some of those practices
indeed are done sitting or lying down with one's eyes closed, focusing on the third eye center. Other of those practices
are focused on a body scan, you know, really focusing
on one area of the body and its contact with whatever surface you happen to be sitting or lying on or can be done walking. In fact, there are walking
meditations done with eyes open. So there are many different
forms of meditation, but today, we are going to focus mainly on how specific types of meditation and specific areas of the brain that are activated
during those meditations change our way of being
in fundamental ways, not just during the meditation practice, but afterwards as well. So if you're somebody who's interested in changing your default
state of mood or of thinking or enhancing your ability to focus or improving your sleep
or improving performance in some cognitive or physical endeavor, meditation is powerful, but you want to make sure that you pick the right
meditation practice. So we will talk about
picking a meditation practice that isn't just feasible
because you'll do it but is actually directed at
the goals specific to you and what you need most. So to give you some sense of
the contour of today's episode, first, I'm going to talk about some of the underlying biology, the mechanisms and the brain areas and also the areas of the
body that are activated during certain forms of meditation, and, equally important, which areas of the brain and body are shut down or reduced in their activity during specific types of meditation. Then I'll transition into how to best do a meditation practice, how to get the most out of
that meditation practice, and then I will talk about how to change or alter your meditation practices according to your specific goals and as you get better at meditation. And this can get a little
bit counterintuitive, but in a positive way. What I mean by that is, for
instance, a lot of people think that as you meditate and
get better at meditating, you need to meditate
more and more and more, sort of like if you get better
at running endurance races that you need to keep
running longer and longer, you know, first a 5K, then a 10K, then a marathon, then ultras. With meditation, it's
actually quite the opposite. The better that you get at dropping into a particular brain state and the more your so-called
traits of brain state shift, not just states as they're
sometimes referred to, but traits, this is a
theme that I've picked up from a terrific book
that I'll refer to later, but the more that you can get into specific neural circuits quickly, actually, the less you need to meditate in order to derive the
benefits of meditation. So that's a wonderful aspect
of meditative practices that's unlike a lot of other
forms of mental exercise and cognitive enhancing exercises. So we'll talk about all of that today, and I promise that by the
end of today's episode, you will have a rich array
of meditative practices to select from, you'll know why each of them work and why they can be directed
toward particular goals and how to do that, and you'll also know how to modify those meditation practices under conditions where
you might get busier or where you're suffering
from lack of sleep, and I think a lot of people
will be excited to know that today we're going to discuss a specific form of meditation that can indeed reduce your need for sleep and still allow you to
enhance your cognitive and physical abilities. 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
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spelled O-U-S, livemomentous.com/huberman. And I should just mention that the library of those supplements is
constantly expanding. Again, that's livemomentous.com/huberman. Let's talk about meditation. As I mentioned earlier, we are going to talk about what
areas of the brain and body are active during meditation
and after meditation and why that can be so beneficial. We will also talk about when
and how best to meditate. Now, this is a topic I've
long been interested in. I was first given a book on meditation when I was in high school because, to make a long story short, I was a bit of a wild one
early in my high school years, and as a consequence of
a program that I was in, somebody handed me a book on meditation. That book is still available now. That book is called "Wherever
You Go, There you Are" by Jon Kabat-Zinn. He was one of the first, not the only, but one of the first people to really start popularizing meditation and mindfulness practices
in the United States. So this was in the late 1980s, and it was really only until recently that there were very few
studies of meditation, although those really
picked up in the '90s. Now you can find many,
many thousands of studies on meditation and their mechanistic basis, so brain imaging studies,
changes in hormones in the body. But in the late 1980s
and in the early 1990s, because functional imaging of the brain, so-called MRI or fMRI, was
really just starting to emerge as a popular tool in
laboratories and hospitals, there really wasn't that much
mechanistic understanding about how meditation worked, but, of course, there
was a deep understanding from cultures outside the United States that meditation was extremely useful. I should just mention, as long as we're talking about
the history of meditation, any discussion about meditation is going to be a discussion
about states of mind, and any discussion about states of mind invokes the word consciousness, a kind of a dangerous topic
to get into in any format because a lot of people
talk about consciousness, but people use consciousness, the word, to mean different things. It doesn't have one standard
operational definition as scientists call it. However, discussions about consciousness are often part and
parcel with conversations about things like psychedelics and kind of alternative therapies. And so in the 1960s and
especially in the 1970s, meditation and psychedelics
were actually close cousins in the conversation about
consciousness and states of mind. That conversation started to split into two different divisions, and I'll explain why in a moment. It gets to a little bit of
interesting academic sociology. But what happened was
there were a couple of guys at Harvard, including
Timothy Leary and others, who got really interested in psychedelics, in particular LSD,
lysergic acid diethylamide. And at that time, that was part of the whole
counterculture movement, it was considered very anti-establishment, and they were really
encouraging students at Harvard to take LSD. They were also very
interested in meditation. But what ended up happening is they essentially got kicked
out or fired from Harvard, and there's a book that I'll refer you to in the show note captions if you're interested in
learning more about all this. But they got kicked out and fired for their emphasis on psychedelics. Now, nowadays, there's a lot
of interest in psychedelics. We've had episodes with
Dr. Matthew Johnson from Johns Hopkins University
who's running clinical trials on psychedelics like psilocybin and LSD for the treatment of depression and PTSD. We've also had Dr. Nolan
Williams on the podcast, my colleague at Stanford
who's doing incredible studies on some of those compounds as well. So nowadays, the conversation
about psychedelics is coming back, and it's somewhat divorced from the conversation about meditation, but in the 1960s and 1970s, the conversation about
psychedelics and meditation was sort of one and the same. That changed in the late
1980s and early 1990s when people like Jon Kabat-Zinn started writing books that
were purely about meditation and suggesting that people
explore meditative practices for the utility to bring calmness, adjust stress, improve sleep, et cetera, divorced from the conversation
about psychedelics. Now, that's not to say that
the scientific community immediately embraced the
conversation about meditation. In fact, it took quite a long while for schools like Harvard and Stanford and other universities around the world to start embracing and
funding studies of meditation, asking what sorts of
brain areas are involved, how it changes the body, and, perhaps most importantly, how a meditation practice
can shift the brain and body when somebody is finished meditating and is off in their life
doing their everyday things. In the late 1980s and
especially within the 1990s, the advent of brain imaging technology like magnetic residence imaging, MRI, or functional magnetic residence imaging was a way to look at the
brain while it was active, not just to get an image of its structure, but also how it's functioning in the areas that so-called light up. When all of that technology
became accessible and popular, well, that allowed a large
number of laboratories to start asking how specific patterns of thinking and breathing, maybe people sitting
in the lotus position, but more often than that, it would be people inside of an MRI magnet because it is a magnet, they sort of put you into a little tube and push you into the tube, not
against your will of course, but put people into the
tube, have them meditate, and then look at how the brain changed and to do that over time. When those studies were done, what was discovered was really
quite miraculous, really. And now we don't think
of it as surprising, but what was discovered was a huge laundry list of brain changes. And then when people were
evaluated in their outside life, so when they would fill out reports of their subjective feelings of happiness or they would report their sleep, or even if objective measures were taken like changes in hormones or markers of inflammation, et cetera, a large list of information
fell out of that which revealed that indeed there are many, a dozen or more clear benefits of a regular meditation practice, and some of those meditation
practices could be quite short. So nowadays, we think of meditation as pretty commonly accepted, and in fact, that has a
lot to do with the fact that many of the major tech companies in the Bay Area during the
2000s such as Google and Apple and any number of different
social media companies and other companies and
business ventures, et cetera, and investment firms all over the world started hiring people to train meditation or had online courses for meditation. So nowadays, we think of
meditation as this thing that almost everybody
understands can benefit us, but we now sit at an interesting frontier where most people think of
meditation as one thing, sort of like the word exercise, which, of course, could
mean weight training, it could mean running, it could mean high-intensity
interval training, all of which, as you know,
will get you different results depending on what you
do, how often you do it, and the specifics of what you actually do. So, too, meditation can give
you very specific results. It can give you more focus,
it can give you better sleep, it can give you a combination of results just like exercise can
depending on the exercise. So what we are going to talk about next is the specific changes
that happen in the brain with specific aspects of meditation. That is, what happens
when you close your eyes, what happens when you
focus your attention inward versus focusing your attention outward because, as I mentioned before, there's third eye meditation
where you close your eyes and focus on that spot
just behind your forehead and you focus on your breathing. There's also meditation practices where you're focusing
on what you're eating with a lot of so-called mindfulness, being very present to
whatever's happening, not letting your mind wander or think about yesterday or tomorrow or what's happening next, but really focusing on the present. There are also meditation
practices, of course, where you are in a format of
interpersonal communication where you're really
listening very intensely. That, too, is a form of mindfulness. So we're going to parse
each of these things, and we are going to ask what's happening in the brain and body during each of these meditation practices so that you can develop
specific meditation practices that you can invoke in your
real life on a daily basis or, thankfully, I would say,
for some who are pretty busy, that you could even do once
a week or even once a month that will still clearly
benefit you in specific ways. I'd like to spend the
next 10 minutes or so talking about the
neuroscience of meditation, and I promise you I'm not
going to just list off a bunch of different brain areas that are active during meditation. That wouldn't be useful to you. In fact, I don't believe in throwing out a lot of nomenclature without also giving some
mechanistic explanation as to what different brain areas do. And you could say, "Well,
what good is it knowing what different brain
areas do and their names if I can't actually
manipulate those brain areas?" But the good news is you actually can
manipulate those brain areas. As I'll tell you today, you can turn up the activity
in certain brain areas and turn down the activity
in specific brain areas with specific elements
of a meditation practice, so that's quite exciting
and quite different really from other aspects of neuroscience that we might discuss on this podcast. So there are a few different brain areas whose names I'd like to arm you with. And again, the names
themselves aren't essential, but if you can grasp even the top contour of what I'm about to say, you'll be in a much better position to parse and use the
information that follows. There's an area of your brain that sits right behind your forehead that's called the prefrontal cortex. Basically, it's the
front bumper of your head just behind the bone, okay? That area just behind your forehead that we call the prefrontal cortex actually encompasses a
lot of different things. And actually, you have two of them. You have one on the
right side of your brain and you have one on the
left side of your brain, and they're connected to one another but they actually do different things. The area that I'd like to
focus on today for a bit is the so-called left prefrontal cortex, or if we were going to
get really specific, we'd say the left dorsolateral
prefrontal cortex. Dorsal means up, lateral
means to the side, so if you want to touch
the left side of your head and move your hand just
toward the midline, toward the sort of top of
your head a little bit, so that's dorsal, and then lateral, as long as your hand is still
on the side of your head, you're in the left dorsolateral
prefrontal cortex, okay? So you've got your hand
probably right over your left dorsolateral prefrontal cortex. That area of the brain, we
know from lesion studies where it's been damaged
in animals or humans and we know from stimulation studies where it's been selectively
stimulated in animals, or yes, indeed, also
it's been done in humans, has an incredible ability to
control your bodily senses and to make sense, that is,
to interpret what's going on in terms of your emotions
and your bodily sensations. So from now on, unless I say otherwise, if I say prefrontal cortex,
I'm specifically referring to the left dorsolateral
prefrontal cortex, but I'm going to shorten that up just for sake of simplicity
and ease of communication. If I'm going to talk about
another area of prefrontal cortex, I'll talk about another area, but if I say prefrontal cortex today, what I mean is left
dorsolateral prefrontal cortex. Stimulation of left
dorsolateral prefrontal cortex or, I should say more appropriately, when your left dorsolateral
prefrontal cortex is active, you are in a great position to interpret what's going
on with you emotionally, to interpret your bodily signals
of comfort or discomfort, and then to make really good decisions on the basis of that interpretation. And that's because the left
dorsolateral prefrontal cortex is in direct communication with and is directly connected
to another brain area called the anterior
cingulate cortex, or ACC. Now, I'm just going to refer
to it as the ACC, okay? The ACC is an area of your brain that is interpreting a
lot of different things about bodily signals, for instance, how fast you're breathing, whether or not your heart is
beating quickly or slowly, and, more importantly, whether or not your heart
is beating quickly or slowly for the circumstance that you are in. So for instance, if
you're running up a hill and you're even in great shape and your heart is beating very fast, it's unlikely that you
are going to be concerned about your heart beating fast because that is appropriate
for the circumstance. However, if you're just walking along and all of a sudden, your heart
starts beating very quickly for no apparent reason, well, then you are going to interpret that as either pathologic or uncomfortable, inappropriate for the context
that you happen to be in. 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 it as
the fear center, et cetera. But your ACC, the
anterior 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 I promise this 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 even on the surface of your body. You know, if you have any pain or an itch or a 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-N-S-U-L-A, insula, and 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, you
know, 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, hey, this is a steep
hill that I'm running up, and as a consequence, whatever heart rate increase
that I'm experiencing or 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, 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 or 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 and 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 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, 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 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 exteroception. What do I mean by exteroception? 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 could be sights or
sounds, touch on our body, sensations withinside our body, et cetera. 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, et cetera, 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 would 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, et cetera, 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 of 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, 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 stomach ache 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 know, 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
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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 as 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 I, 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 exteroception,
spelled with an E. Exteroception 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 so incidentally,
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, exteroception, and usually also toward our inner state. 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 a sandwich shop about to order a sandwich
and you're reading the menu, so that's exteroception, 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's in it, what you like,
what you don't like, et cetera. That's splitting interoception
and exteroception. 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 interoception, something very important happens. What happens is that those two regions, the ACC, the anterior 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 exteroception 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
interoceptively 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 heart beat. Some people are very good, meaning 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, 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 the sensations
within their stomach. Whereas other people who are 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. They're, 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 exteroceptive 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 important later
when 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
exteroceptive 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 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 note, there's this continuum of perception, interoception and exteroception. Closing your eyes increases interoception. Opening your eyes dramatically
increases exteroception 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 and 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 and it'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've liked to find, but a few studies of, 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-canceling 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
interoceptively aware or not, more exteroceptively 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 if 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 red, et cetera, 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, will 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 exteroceptive 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
loathe to find out later that you had food 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 exteroception? Well, we know what it
means neurally, right? We know that if you are
more interoceptively aware, your insula and ACC are active,
but that's not very useful. 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,
it has a very cool name. It talks about something very important that will come up again and
again in today's conversation, and 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 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, your
thinking, and your memory, your cognition onto one of those things and be very, very present or the past and 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, it 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
Super Bowl, NBA Championships, and Stanley Cup, if you will, for you 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 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 prove 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
widely available and in use, so again, 2010. So they basically pinged people, they contacted people on their
iPhones many times per day, and they did this for
well over 2,200 adults. They had a mix of male and
female people in this study. The mean age was 34 years,
but there was a range, mean, of course, being average, but there were a range of
different ages and so forth. And at any moment, they asked people, "What are you feeling right now?" And they also asked them,
"What are you doing right now?" So they were looking for
the match or mismatch between what people were doing
and what they were feeling. They were essentially trying to probe what people were thinking about, and they also addressed that. And they came up with a kind
of a bubble chart, if you will, where the bigger the bubble, the more answers came back
about one particular thing, and they assessed whether or not people were happy or not in
that moment, or sad or not, whether or not they were focused on what they were doing or not. There are a lot of bubbles in this chart, so I'm not going to read them all. But the important points
that came from the data, and, again, this is a very large data set, was that, and here
again, I'm paraphrasing, first, people's minds wandered frequently regardless of what they were doing. In nearly half of the samples taken, people were generally
thinking about something else, except, it turns out, there's this one little bubble sitting way far out on the horizon here, people claimed, and I'm
inclined to believe them, that they tend to be very
focused on making love if they were making love in the moment where they were pinged on their iPhone. Now, why their iPhone was
there with them at that moment, I don't know. That wasn't included in this
description of the study. But all the other activities,
grooming and self-care, listening to the news,
watching television, relaxing, working, et cetera, et cetera, during all those activities, people claimed that their
mind wandered a lot. And then they also assessed,
of course, their mood and how those people
felt at any given moment depending on what they were doing and how well their mind and their emotions matched what they were doing. And what they say here is second, they revealed that people were less happy when their minds were wandering
than when they were not, and this was true during all activities. And then third, what people
were thinking at a given moment was far better a predictor
of their happiness than what they were doing. So this is interesting and I think matches a lot
of people's experience. In fact, I think as you
hear about this study, many of you will probably
just say, "Well, duh." I mean, if you're working
and you don't like your work and you're thinking about
something bad that happened, well, then of course you're
not going to be happy. But the key point of this study is that it did not necessarily
have to be the case that people were thinking
about something unpleasant. In fact, if people were working and they were thinking
about something else that was pleasant, that
also made them feel unhappy. In other words, the mismatch
between being in an activity and having our mind elsewhere led people to report themselves as feeling more unhappy in that moment. And when you total this up,
what you find is that people are often not present
to what they are doing, and that is a great source of unhappiness, even if their thoughts are
those of happy, joyful thoughts. So this is interesting and I think runs counter to
what most of us have heard or have been taught, which is, you know, think good thoughts, you know, try and suppress bad thoughts, have a good internal landscape, you know, create a good narrative. That is all true, but
equally if not more important is to have the ability to be fully engaged in what you are doing at a given moment. That is the strongest
predictor of being happy. And there were several other studies that followed up on this, but their conclusion that they put in the final short paragraph of this paper I think really captures it beautifully. They say, and here, I'm quoting directly, "In conclusion, a human
mind is a wandering mind, and a wandering mind is an unhappy mind. The ability to think about
what is not happening in a moment," I added
the in a moment part, "is a cognitive achievement that comes at an emotional cost." So I know I'm not alone in
believing that this paper, A Wandering Mind is an Unhappy Mind, and we will provide a link to this paper in the show note captions, is absolutely key in understanding why a meditation practice is so important because a meditation practice is really about adjusting your place along that
interoceptive-exteroceptive continuum to what you happen to be
experiencing in that moment. And while most people think
of a meditative practice as focusing on what's going on internally with your eyes closed, third eye center, focusing on your breathing, et cetera, for any number of minutes or
maybe even an hour or longer, there are other forms of meditation in which your exteroception dominates and which you are actively
focusing on things outside or beyond the confines of your
skin and internal landscape, and that, too, is meditation. And if we are to take the work
of Killingsworth and Gilbert, this A Wandering Mind is
an Unhappy Mind, seriously, and I know a number of
other laboratories have and have supported this
research with their findings again and again and again, what this means is that meditating is not necessarily a practice that we do divorced from the rest of life. Meditation and mindfulness in particular, being present to what we
are doing in a given moment is one of the essential keys
to happiness and improved mood even if what we are doing is unpleasant. So that brings us to a tool, and it's a tool that any
and all of us can use whether or not you tend to
be interoceptively dominant, right, that you tend to pay more attention to your bodily sensations,
or exteroceptively dominant. And, again, if you don't know
the answer to that question, there's a simple test that you can do. You can just sit down or
lie down, close your eyes, and you can ask yourself or assess whether or not your
attention tends to fleet to things outside of you, right, cars honking or going
by, people in the room, or whether or not you
tend to be able to focus on your internal landscape to the exclusion of exteroception
and attention to things outside the confines of your skin easily. Now, of course, this will
depend on context and situation, even how well rested you are, et cetera, but that's exactly the point. This is the sort of thing you want to do every time you decide to
do a meditation practice. In fact, I would suggest that you use this to determine what meditation
you do at any given moment. So let's say you are somebody
who is a regular meditator or let's say you're somebody
who's never meditated and you'd like to develop
a meditation practice. I suggest that you do a test of whether or not you are
more interoceptively dominant or exteroceptively
dominant in that moment. Again, this is not a personality trait. This is a question about where
you happen to be in a moment. So let's say you're on a
plane or you're in the car. If you're in the car, please don't close your
eyes while driving, that's sort of obvious, but
do this in a safe way, please. But stop, close your eyes, and assess whether or not you can access and focus your attention
primarily on your internal state or whether or not your
attention and perception gets pulled to something
external, to exteroception. And, again, that will vary depending on circumstance and who you are. Then I suggest opening your eyes and trying to focus your attention to something external to you and seeing or evaluating the extent to which you can divorce your perception from sensations that occur at the level of your skin or internally. Now, I should say that
there's no technology, at least not that I'm aware
of, absence of fMRI machine, in which case, you are
inside an fMRI machine while you do this. But unless you are in that experiment, and most of us aren't, there's no technology that
can tell you, for instance, whether or not you are
interoceptively dominant or exteroceptively dominant and whether or not the
ratio is, you know, 75 to 25 or what have you at any given moment. You have to assess this subjectively. However, if you sit down, for instance, and you notice that you can
equally split your attention between internal sensations
and external sensations or whether or not you find yourself pulled into external sensations when you're trying to focus inward or you find yourself pulled inward when you're trying to focus outward, well, that will dictate
the sort of meditation that you perhaps ought to
perform in that moment. Let me give an example
of how you would do this. You would stop in some way, so sit or lie down, close your eyes, and evaluate whether or not
you can essentially rule out or eliminate attention
to all outside events. Most people won't be
able to do that entirely, but try and focus your attention, for instance, on your breathing or the typical third eye center, you know, focusing at a spot
right behind your forehead. If you feel you can do
that reasonably well to the exclusion of what's
happening around you, well, then an important question arises. Should you meditate in a way to enhance that interoceptive awareness? Or rather, should you meditate in a way, for instance, with your eyes open and your attention on a particular portion of the landscape you're in like a tree or maybe even,
you know, an object or a plant or something else in your
immediate environment to try and cultivate or enhance your exteroceptive awareness? That's up to you, but my bias would be one in which you work against
your default state. Again, the default mode
network is where you land on this interoceptive-exteroceptive
continuum. It's going to lead to more mind wandering, whereas when you encourage or we could even say force
yourself a little bit to anchor your attention to either inside your
body or outside your body, and you make that decision according to what you
are doing less easily, well, then you are actively
training up the neural circuits. You are engaging
so-called neuroplasticity, the brain's ability to change
in response to experience. You are deliberately engaging a shift along that continuum. To make this crystal
clear, what I mean is this. Let me give an example. If I were to sit down and I
wanted to do some meditation, let's just say three
minutes of meditation. There's good evidence that even
three minutes of meditation can be beneficial for a variety of things, including enhanced focus and
enhanced anxiety management. Let's say I sit down and I notice that I
can really focus inward on what's happening at
the level of my skin and my internal organs, and
I can rule out everything. Maybe that's 'cause the room is quiet or maybe it's just because
my brain is in a state that I'm particularly good
at that at that moment or maybe it's just a natural ability. Well then I would opt for a
three-minute meditation practice in which I deliberately exterocept, that I build up the circuitry to focus on something external to me because I want, and I think
most people would like, to have an adaptive mechanism within them so that they can slide
along that continuum and they don't default to whatever happens to be
easiest for them in that moment. Now, if I were to sit down and try and focus on
what's going on internally and I kept getting distracted by things happening outside of me, opening my eyes or feeling like
I need to reach for my phone or paying attention to
the sounds in the room, well, then I would actively
engage a meditation practice, in this case, a three-minute
example but it could be longer, where I'm deliberately
trying to focus my perception on events at the level of
the confines of my skin and internally. Why do I say this? Well, you know, I love to use
the phrase anytime with kids, you know, when they say
"This is really hard or something's challenging," or adults will say, "That's really tough." Well, as my graduate advisor used to say, that means you're learning. If something were easy, if you can perform any
activity or thought, et cetera, well, then there is absolutely zero reason for your neural circuits to change. It's the friction, it's the
feeling that something is hard that turns on the enormous
variety of mechanisms at the level of cells, et cetera, that allow you to potentially
change your neural circuitry. So challenge and discomfort is the signal to your brain and body that something needs to change, so I'm encouraging you to
embark on meditative practices that are not your default, okay? To essentially go against the grain of where your interoceptive
bias or your exteroceptive bias happens to be at a given moment. And, again, this will change. For some of you, this
will change across the day where early in the day,
you are very, very good at doing an
interoceptive-biased meditation, and later in the day, you aren't. I actually believe, based on
the data that I've covered, and we'll get into a few
more papers about this, and my lab is actively
working on this as well, that a meditative practice can
be made far more effective, that is, it can invoke
more neuroplasticity, more shift in brain
states and brain circuitry if we do not take the easy path, that is, we go against the grain of what our brain would
naturally do in a given moment. So if you're in a crowded airport and you're finding that
everything's very distracting, well, then that would be a great time to do some interoceptive
focused meditation. Whereas if you are really in your head, you know, you're looping thoughts about the past and present, maybe you're even in obsessive thought, well, that would be a terrific
time, an ideal time really, to do a short meditation focused on something external to you. In both cases, whether
or not you're focused on interoceptive bias
or exteroceptive bias, you are going against, or I
should say you're pushing back against your default mode network. I would argue it's going
to be far more effective, that is, you're going to
reduce or shift the activity of that default mode network far more and in a far more beneficial way if you actively try and suppress your bias toward being more
interoceptive or exteroceptive. Now, I think that's immensely beneficial, both for the immediate
changes that you experience, what others have called a state change, because that's what it is, and it also can lead to,
as we referred to earlier, more neuroplasticity, more
changes in the brain circuits that underlie your default mode network and lead to what are called trait changes. And I want to be very clear
that I am not the first to make this state
versus trait distinction. That's a distinction that was raised in a really wonderful book. In fact, I can't recommend
this book highly enough. The book is "Altered Traits:
Science Reveals How Meditation Changes Your Mind, Brain, and Body." This is a book by Daniel
Goleman and Richard Davidson who've done terrific
work and many writings and many TED Talks, et
cetera, about meditation. I would say that circa 2016, 2017, this book really captured what I believe to be the
most essential elements of the science of meditation and a lot of the history of it as well. Today, we are focusing on much of what's covered in this book but also a lot of things that have happened, excuse me, since 2017. In fact, most of the papers
that I'm going to talk about are papers that were published after 2017. But, again, this is a wonderful book where they very clearly distinguish between state changes and trait changes, trait changes being the
more long-lasting ones. My read of this book and
the literature that follows is, again, that when you
sit down to meditate, it is going to be most effective to do that interoceptive,
exteroceptive bias assessment. Ask yourself whether or not
you are more in your head or outside your head, if you will, and then to do a meditation practice that runs counter to
where you happen to be at, that is, that pushes you more externally if you're in your head, and if you're more focused on
what's going on around you, that pushes you more internally. Now, I think most people are familiar with how to do an
interoceptive-biased meditation. Again, that would be setting a timer. Maybe you don't have even set a timer, you just sit or lie down, close your eyes, focus on that third eye
center behind your forehead or focus on your breathing
or your bodily sensations. That's typical and often discussed. Exteroceptive based meditations, you pick a focal point outside or beyond the confines of your skin, so that could be, for
instance, a point on the wall if you are indoors, it could be a plant, it could be a point on
the horizon far away. What you will find is
that your visual system will fatigue a little bit when you concentrate your
visual focus at that location. I want to remind you
that it is perfectly okay and, in fact, necessary to blink, so you should blink,
you can relax your face, you can change your expression. There is no rule that says
that you can't do those things. This is not, you know, just
beaming a particular location in space and holding your eyelids open. I've been accused many times
of not blinking very often. That's for other reasons. It's part of the way I access memory about what I want to say. I don't use a prompter here, so I'm accessing from a sort
of internal image in my head. That's how my memory works. But in any case, if you're going to do an
exteroceptive-biased meditation, there is absolutely no reason why you wouldn't look
away from that location every once in a while in the same way that if you were focused
on internal thoughts with your eyes closed and
focused on your breathing, every once in a while, your thoughts will skip
away from that breathing or from your third eye center. In fact, and this is discussed
in the book "Altered Traits" but by many other people as well, one of the key elements of
any meditative practice, whether or not it's
interoceptively focused or exteroceptively focused, is that it's really a refocusing practice. The more number of times that
you have to yank yourself back into attending or perceiving
one specific thing. In other words, the more
times your mind wanders and you bring it back, actually the more
effective that practice is. Again, if you can just
focus on one location with laser precision and your mind never darts away from that and you don't have to bring it back, well, then there's no neuroplasticity, nothing needs to change
because your nervous system will effectively know
it's performing perfectly. So if you're somebody who
tries to do meditation and you find that your mind just wanders, just remember every
time you scruff yourself and pull yourself back to focusing on some location externally or focus back on your breath
or your third eye center, each one of those aren't just
opportunities to do better, they are essential to
the improvement process. Think about them as ascending
a staircase of refocusing. Every time you refocus, you're
going up one more level, another stair, another
stair, another stair, and I think that will move you away from the kind of judgmental process of thinking, "Ugh, like, I
can't focus on anything." Pretty soon, what you'll notice is that the refocusing
process will happen so quickly that you don't even perceive it. And, again, this is
something that's borne out in the neuroimaging data. A lot of people think that they can focus with laser precision, but actually, what they
are better at doing is refocusing more quickly
and consistently over time. There's a classic study about this in very experienced meditators
that was done in Japan where they had people with varying levels of meditation ability, so some who had never meditated, others who were really expert meditators with many hundreds if
not thousands of hours of meditation under their belt, and they had those
people listen to 20 tones repeated over and over, the same tone, and they found that the expert meditators could really focus, and they
did this by brain imaging, they could really focus on all 20 tones, whereas most people kind of attenuate or what's called habituate to the tone so that by the 10th or 11th tone, their mind is really
going to something else. Now, that's wonderful, but
that really just tells us the expert meditators have better focus. But it turns out that the more
modern neuroimaging studies have shown that they
don't have better focus such that they're staying in
a very narrow trench of focus. What they're doing is
they're exiting focus and going back in more quickly,
more quickly, more quickly over and over again. So rather than think about
your ability to focus, think about your ability to refocus, and the more number of
times you have to refocus, the better training you're getting. So earlier, I mentioned doing
this interoceptive-biased or exteroceptive-biased
meditation for three minutes. Why did I say three minutes? Well, three minutes seems
like a reasonable number for most people to do
consistently, you know, once a day. And in fact, there are some studies of one-minute meditations
and three-minute meditations and 10 and 60. My laboratory has been studying
a 5-minute-a-day meditation, and that clearly has benefits, but I think it's also clear
that by three minutes, many of the benefits
are starting to arrive. And so while I'm not pointing at any one particular data point here, it's very clear that forcing oneself to direct one's perception,
that is, your attention, to your internal state or
to something external to you is immensely beneficial
if you do it consistently and is, again, especially beneficial if you're focusing your attention on the portion of your experience, either internal or external to you, that is not the one that you would default to in that moment. And some people have taken
this to the extreme to say that, you know, you can even
just move about your day, and then every once in a while, just do a one breath meditation. To be honest, when I look
at the whole of the data, it seems as if it doesn't really matter in order to derive most of the benefits of a meditation practice. Now, I'm a big fan of some
of the newer meditation apps that are out there. One in particular that I've been using and that actually I started using because my dad is a big fan of it and he does now fairly long meditations. He's doing about 10 or 20 minutes at least every other
day and often every day, and he convinced me to
check out the Waking Up app that Sam Harris has put out. I looked at it, I think some
of it sits behind a paywall, but you can access much of
it or at least do a trial and try it out without having
to get behind that paywall. They're not a sponsor of this
podcast, I should mention, but I decided to use the Waking Up app. I think it's terrific, and I think one of the
reasons it's terrific is that Sam includes short descriptions of what meditation is doing and what a specific
meditation can do for you just prior to doing that meditation. So those meditations can be quite brief. Some of them are a minute
long, two minutes long, some are longer or even
quite a bit longer. That app, I think, includes
a variety of meditations that really encompasses the
huge range of possibilities that are possible with meditation, and that, at least by my
experience of the Waking Up app, has led to my most consistent
meditation practice. And, of course, I would love to get Sam on the podcast as a guest so we could talk about
the sort of underpinnings of the Waking Up app and his views on
everything from meditation to, I know he's big in the discussion about free will and consciousness, some of the very deep and
somewhat abstract discussions. I really hope to get Sam on the podcast at a time not too far from now. Meanwhile, we've never met in person, but I absolutely love
the Waking Up app, Sam, and I know my father does as well, and I know many of you already use it. If you haven't tried it already, I really do encourage you to check it out. I want to talk just briefly about this third eye center business because it turns out to
be pretty interesting. The third eye is actually a name that's been given to
another neural structure, or I should say structure
because it's not strictly neural, and that's the pineal gland, and this has an interesting history. I promise I'm not taking
off on a tangent here that isn't relevant to meditation. So you have a brain of course, and on both sides of your brain, you tend to have mirror
symmetric representations of the same things. What do I mean by that? Well, you have a prefrontal
cortex on the right, you have a prefrontal cortex on the left, and they actually do
slightly different things. Language is sometimes
lateralized to one side, but in general, for every structure that you have on one side of the brain, you have the same structure on the opposite side of the brain. There's one clear exception to that, and that's the pineal gland. The pineal gland is the
gland that makes melatonin, which, at night when it gets
dark, secretes melatonin, and that melatonin makes you sleepy, it helps you fall asleep
but not stay asleep. Descartes, right, the
philosopher Descartes asserted that the pineal
was the seat of the soul because it was the one
structure in the brain that he saw was not on
both sides of the brain, it was only one of them and in the middle. Now, I don't know if it's
the seat of the soul or not, I'm not in a position to
make assessments like that. But what do we know about the pineal? The pineal, as I mentioned, is involved in releasing melatonin, it does a few other things as well, but it is also considered the third eye for a couple of reasons. One is that it responds to light, although, in humans, not directly. So in birds and lizards and snakes, they actually either have a thin skull, or, believe it or not, two
holes in the top of their skull that allow light to go directly in. If you look at the head of a snake, light can go directly into
their brain through these holes and activate the pineal
to suppress melatonin and control their
wakefulness, sleep rhythms. In birds, they don't have
holes in their skull, but they have very thin skulls. And, believe it or not, light can penetrate the thinness
of the skull in many birds and communicates information
about time of day and even time of year, and that's translating to hormonal signals such as melatonin release from the pineal. And so the pineal has
been called the third eye because it's a light-sensitive
organ inside the brain. In humans, the pineal sits
deep, deep, deep to the surface, and light cannot get in there. In fact, if light can get into your brain, unless you are part of
a specific experiment where that's the intention or you're having neurosurgery
or something of that sort, then you've got serious issues happening. That pineal sits deep, deep, deep near what's called the fourth ventricle, and it absolutely should
not see light directly. So the idea that the pineal is the third eye in humans is not true. It just isn't true. So anytime someone says, "Oh,
the pineal is your third eye." That's not the third eye center
that people are referring to when they talk about meditation. Now, you'll see a number
of different forms of art where it will be a picture of a face and the eyes will be
closed or sometimes open, and there'll be literally a third eye, like a cyclops eye in the
middle of the forehead. That has been proposed for
many thousands of years to be, quote, unquote, the
seat of our consciousness. Now, that's interesting because that real estate
behind the forehead actually turns out to be
the prefrontal cortex, which we know from lesion
studies and stimulation studies, if you remove that brain area,
people become very reflexive. They are not thinking intentionally, they don't become deliberate. In fact, and this is
kind of an eerie result, but if you inactivate, you
turn off the prefrontal cortex and you give somebody the opportunity to play a shooting game, for instance, their accuracy goes through the roof. They become essentially like a machine. They see a stimulus, they shoot at it, they see a stimulus, they shoot at it. Their accuracy is exceptional, but their ability to distinguish between enemy and friend
completely disappears. So they become a highly effective motor, or I should say sensory motor machine, but their assessment and their judgment about right or wrong
completely disappears. This is also true for people
that have prefrontal damage. They often will have
inappropriate behavior or a hard time suppressing
behaviors, et cetera. So the third eye center as the seat of consciousness
and our intention is something that makes sense generally with what we know about the
neuroscience and neurology, but there's something more to it that I think is especially
important for all of you that goes beyond anything
about ancient traditions or pineals or birds or snakes and pits in the top of the
head, and here's what it is. The brain itself,
meaning the brain tissue, does not have any sensory neurons. What do I mean by that? Well, if I touch the top of
my hand, I can feel that. If I want to sense my heartbeat, if I work at it, I can feel that. If I want to sense how I feel internally at the level of my stomach, is it full, is it empty,
am I hungry, is it acidic, does it ache or does it
feel pleasant, et cetera, I can sense that. And that's because we have sensory neurons on our skin and in our body, et cetera. We also have sensory neurons in our eyes that let us perceive things externally. We have no sensory neurons on our brain. This is one of the reasons
why you can remove the skull and do brain surgery on
somebody who's wide awake and be poking around in there, and they don't need any
anesthetic on the brain itself. They need anesthetic
for the incision site, but they don't need
anesthetic on the brain because it has no feeling. You have emotions, but there's no feeling. So normally, we are perceiving
and paying attention to what we are sensing, either externally, sight and
sounds, again, exteroception, or internally, interoception,
touch, et cetera. But by focusing our
perception and our attention not on our bodily
surface like a body scan, but to a point a couple
centimeters or inches behind our forehead, we essentially are
bringing that attentional, that perceptual spotlight to a location in which
there is no sensation. There's nothing to feel there. And when we do that, by closing our eyes and focusing on that, quote,
unquote, third eye center, which is the prefrontal
cortex, to be quite honest, when we do that, something else happens. And what happens is when
we are not thinking about and perceiving our sensations,
because there are none there, our thoughts and our
emotions and our memories sort of mushroom up. A better way to put it
would be that they geyser up and take on more prominence
in our perception. What I mean by this is that normally, you know, I'm not thinking
about the contact point between me and this chair, but as I'm speaking, I'm
in contact with the chair and those neurons are firing. But if I focus my energy
and attention on them, they're going to fire the same but more of my perception goes there. Similarly, I'm thinking things
all the time. You are too. And I'm perceiving things all the time, and I'm remembering things all the time, and I'm anticipating things
all the time about the future. But by focusing my
attention on the one organ for which I have no sensation, that is, my brain, well, then thoughts,
feelings, and memories, feelings meaning emotional feelings, start to grow in their prominence in my awareness and in my perception. And so this is why when you sit down to
a meditative practice, if it's a meditative practice
where you close your eyes or you're focused on
that third eye center, where you're focused on your brain as opposed to your bodily surface or something external to you, the thoughts seem to come by in waves, and they can almost be overwhelming. It's very hard to, as
it's often described, just sit back and watch
your thoughts go by because there are so many of them. Actually, the best way to stop thinking is to really focus on something external or to focus on sensation. That's less thinking than it
is perceiving senses, okay? So I don't want this to get too abstract. When people talk about
the third eye center, they're not talking about the pineal, they're talking about prefrontal cortex, and when you direct your own attention to the very area of your
brain that directs attention, there's nothing to sense there. The only things that will
become present to you are feelings, emotions, that is, thoughts and memories, and they will often arrive in what seems to be a
very disorganized fashion. And the reason they arrive in
somewhat disorganized fashion is because, normally, we just don't perceive things that way. Normally, we are splitting our attention, our perception, that is, to multiple things, our
sensation and our thoughts. When we put all of our
perception into our thoughts, we see how disorganized,
how wandering they are and how, in fact, how random
and intrusive those can be. Again, random and intrusive. And much of what we talked
about in that paper earlier, the one where they asked people, what are you doing and
what are you feeling and how happy or how unhappy you are, what they discovered was that most people are sort of in their head a lot. They're not really present
to what they're doing, which leads me to the
statement that I believe, at least based on the
data, that paper included, that most people have
an interoceptive bias. They're focused more on
what's going on internally than they are focused on
what's happening externally. There are certainly people
who for the opposite is true, but I think that this is an issue because we hear so often about the need to do a meditation practice
that allows us to focus inward and that we're getting yanked around by all the stressors of
life, et cetera, et cetera. And we are, we're getting yanked around by all the stressors and demands of life. But as we do that, we tend to be very focused
on what's happening with us. The data clearly point to the fact that being mindful and being aware can enhance one's level
of presence and happiness. But we can go so far as to say that being mindful and
aware of what's happening, not just with us but external to us in our
immediate environment, that includes what other
people are saying and doing, that also can really enhance our sense of well-being and happiness. At least that's what the data point to. Let's briefly recap
where we've been so far. We've talked a little bit
about the brain networks that are activated during meditation, which include prefrontal
cortex, ACC, the insula. We also talked about the difference between interoception and exteroception and the importance of
assessing where you are along that continuum. And I should mention, of course, that you can be right in the
middle of that continuum. You might sit down to do meditation and find that you are
smack dab in the middle of being able to attend
to things outside of you but also attending to
things inside of you. In which case, I suggest
doing a meditation that is either exteroceptive-biased
or interoceptive-biased. But as I mentioned earlier, if you find that you are more,
quote, unquote, in your head or in your body, well, then focus on an
exteroceptive-biased meditation to build up that set of circuits. Whereas if you are more
exteroceptively focused at any given moment, well, then I encourage you to do an interoceptively
focused meditation practice. And as I mentioned earlier, there is this issue of
how long to do a practice. There are a lot of
different data on these, but some of the practices we've covered on this podcast before when we had guests, for instance, highlighted the 13-minute meditation that Dr. Wendy Suzuki from New
York University's laboratory has popularized, and they popularized it because
they have a wonderful paper that we will provide a link to which shows that a daily
13-minute meditation, which is of the traditional third eye, interoceptively biased,
focus on breathing, and focus on that location directly behind one's forehead or both, that meditation done daily
for about eight weeks, maybe shorter, but in
that study, eight weeks, greatly improved mood,
improved ability to sleep, improved cognitive
ability and focus, memory, a huge number of metrics were
looked at very specifically. So that's a terrific one. And you may be asking yourself, do you need to do the full 13 minutes? Could you get away with five
minutes or three minutes? Well, my laboratory has shown
benefits in stress reduction, improvement in sleep, et cetera, with a five-minute-a-day meditation. However, in trying to establish how long you should meditate, I would ask yourself
a couple of questions. First of all, what is a practice that you can do consistently? And by consistently, that doesn't necessarily mean every day. If you answer the question
about consistency honestly, and you find that you can only do one meditation session per week, well, then I would encourage
you to go a little bit longer, maybe 10 or 15 minutes,
maybe even 30 minutes. Again, understanding that
you're going to have to refocus repeatedly throughout that meditation regardless of whether
or not you're focusing on internal perceptions
or external perceptions. If, however, you can set aside
5 or 10 or 15 minutes per day and you can meditate every day, well, then I think you
have a bit more flexibility in terms of how long you meditate. Maybe it's three minutes one
day, one minute the next day, 10 minutes the next,
and so on and so forth. Just like with exercise, the
key component is consistency, and this is borne out in all the data that's covered in "Altered Traits." It's also borne out in
all the recent studies that have come out since
that book was published. Consistency is key, so ask yourself what
you can do consistently, and also don't necessarily burden yourself with always having to do the same amount or duration of meditation. So earlier, we decided
we were going to parse or fine slice the meditation practice, and indeed we've been doing that. We've talked about interoceptive
versus exteroceptive bias, and we've been talking about where you place your
perception or your focus. Another key component of meditation is the pattern of
breathing that you embrace. In fact, the pattern of breathing that you embrace during
your meditation practice can itself be its own form of meditation. What do I mean by that? Well, these days, we hear
a lot about breathwork. Breathwork has really grown in popularity in the last 5, 10 years, and there are a number
of reasons for that. First of all, I think we
need to credit Wim Hof, or can we call him, I think appropriately, the Great Wim Hof? You know, certainly there
were people before Wim who were doing deliberate breathwork and talking about deliberate breathwork, but it was really about 2015 or so that Wim Hof started to grow
in recognition and popularity for a particular style of breathing, which, in the laboratory, we
call cyclic hyperventilation. I know there are other names for it that come from ancient traditions. He named it, or people
named it after him, Wim Hof. Wim Hof, for those of you that don't know, is a Dutchman who is known
to hold many world records for deliberate cold exposure, including swimming under
icebergs, longest period of time buried in ice up to his neck, et cetera, but who's also expert in the use of breathing in particular ways in order to manage and maneuver
through those challenges. And he started speaking about different patterns of breathwork, in particular, the use of
cyclic hyperventilation, deep, deliberate breathing, so big inhales [inhales],
exhales [exhales], big inhales [inhales and exhales] exhales. In the laboratory, again, we call that cyclic hyperventilation. It's very clear from studies
both done on Wim specifically but on the general population as well by my lab and other labs that that pattern of
cyclic hyperventilation, of deliberately breathing
deeply and repetitively, typically in through the
nose, out through the mouth, generates a lot of adrenaline or causes adrenaline release
from the brain and body. It, quote, unquote, heats up the body. Indeed, it raises body temperature, but the liberation of adrenaline
does a number of things to shift the state of the brain and body. That, more or less, is
what Wim Hof breathing is, although Wim Hof breathing, or some people will
call it tummo breathing or cyclic hyperventilation, is not a pattern of breathing typical of most meditations
that have been discussed, at least not in the research literature. Now, that's not to say that
cyclic hyperventilation can't be incorporated into
a meditation practice, but Wim Hof breathing aka
cyclic hyperventilation/tummo is typically considered
its own practice, okay? Its own breathwork practice
divorced from meditation. It might have a meditative component, but it's not often discussed as meditation or as part of meditation. More typically, a meditation practice involves slowing one's breathing, and this could be in the
form of cyclic breathing of inhale, exhale, inhale,
exhale, which is cyclic, or, in some cases, doubling up
on inhales and then exhaling, so inhale, inhale, exhale,
inhale, inhale, exhale, or controlling the duration
of inhale, breath hold, exhale, breath hold, repeat, so-called box breathing where the inhale, the hold,
the exhale, and the hold are of equivalent durations. Any number of different
breathing patterns, slow cyclic breathing, box breathing, a cadence of three to six seconds in, holding for two seconds,
and seven seconds out, regardless of what cadence
of breathing one uses, there is a tendency during
most meditative practices to slow one's breathing
and/or control one's breathing in deliberate fashion. This is essential because
when we default our breathing, that is, when we don't pay attention to how long we are inhaling
relative to our exhales, when we don't deliberately exhale, that is, normally we just passively exhale but we actively inhale, I repeat that, normally, when we're not
thinking about breathing, we deliberately inhale, there's a a motor command that's
sent to inflate the lungs, and then we passively exhale. But in many breathwork practices
or meditation practices, we actually actively exhale as well. Well, when we do that, a
number of things happen. First of all, it forces us
into interoception. Why? Because the diaphragm, the muscle that helps
move the lungs essentially and create a specific cadence of breathing or depth of breathing as one would with box breathing or deliberately slow breathing, well, that muscle resides inside of us, and so when we focus on our breathing, more often than not, we aren't focused on the actual air leaving
our nasal passages or mouth, maybe a little bit, but more typically, we are forced to focus or we just default to focusing on the movement of our
diaphragm or of our belly or the rising and falling of our chest. All of that is to say that by deliberately
focusing on our breathing, we shift to interoception. So breathing and specific
patterns of breathing are sort of along for
the ride in meditation, but the reverse can also be said, that when we focus on our breathing, we shift to interoception and
away from external events. It doesn't mean we can't
still pay attention to external events, we
can still exterocept, but at least some portion
of our perception, of our attention shifts to interoception. So we of course need to
breathe to stay alive. We have to breathe at least every so often in order to stay alive, so, of course, breathing is
part of any meditative practice, just like it's part of any
living activity, even sleep. But if the first component of meditation is to direct our perception
in a deliberate way, using that prefrontal cortex, to a specific location,
either on the surface of or within our body or
external to our body, or both, but typically one or the other, then we can say that the second element of a meditative practice is
the pattern of breathing, and we can ask ourselves, can it and should it be deliberate or not? In other words, do we just default to however we happen to be breathing, or should it be deliberate? That is, should we be controlling
the depth and the cadence? And I do believe that, based on what we know about the capacity for specific patterns of breathing
to shift our brain state, that controlling one's
pattern of breathing during meditation can
be enormously useful, and that is true regardless
of whether or not one is focusing on interoceptive
perceptions within our body or exteroceptive perceptions. So that raises the question, how should we breathe during meditation? Well, there is, again, no simple one-size-fits-all rule there, but there are some general
rules of respiration physiology that can help us access and
develop a meditation practice that is going to best serve our goals. And since this is not an
episode all about respiration, and we will do one, I simply want to give you the basics of what respiration can do to shift your brain and body state. Before I do that, however, I want to give a very
specific instruction, which is when you sit down to meditate, or if you're going to do
your meditation walking, that's fine too. I should just say when
you are about to begin your meditative practice, you need to ask yourself a question. Do you want to be more relaxed
than you are at present, or do you want to be more
alert than you are at present when you exit the meditation practice? Do you want to calm down, or do you want to become more alert? Simple question. You can
decide from session to session. You could even switch within a session. But just as you need to
assess whether or not you are leaning more
interoceptively or exteroceptively, you also need to ask yourself, do you need to calm down
or want to calm down, or do you want to be more alert at the end of your meditation session? Or maybe you want to go into
a state of deep relaxation and then exit with more alertness. The way to do that is very simple using breathwork and specific
patterns of breathing. And here is the general
rule that is supported by all the respiration
physiology that I'm aware of. I'm oversimplifying here, but I'm oversimplifying intentionally so you can simply apply the tool. And then, as I mentioned
before, we will do an episode all about respiration
physiology in the future. Essentially, if your inhales are longer and/or more
vigorous than your exhales, then you will tend to be more alert or you'll shift your brain and body towards a state of more alertness. This is simply based on the
way that the neural circuits like the pre-Botzinger nucleus
and the parafacial nucleus that govern respiration
physiology and alertness, it's simply the way they work. They communicate with brain areas that release noradrenaline
and norepinephrine, et cetera. In contrast, if you
emphasize longer duration and/or more vigorous exhales
relative to your inhales, you will tend to relax more, you will tend to calm your nervous system. Now, you might be saying,
"Okay, I understand what it is to make an inhale longer than my exhale, but how do I make it more vigorous?" Well, it simply means drawing
more air into your lungs more quickly than you allow
yourself to exhale that air. So an example of inhale-biased breathwork would be [inhales and exhales]
[inhales and exhales], so there's an active
emphasis on the inhale, and it's a little bit
longer than the exhale which is passive. Conversely, if you want to relax, then you want to extend your exhales relative to your inhales, and you can even make them active exhales. So it can be inhale [inhales and exhales], exhale [inhales and exhales]. That's going to shift your nervous system in a direction of more calm. And, of course, if you would like to stay at the level of alertness aka calmness because those are two sides of the same seesaw or the same continuum, if you'd like to be right where you're at at the end of your meditation
as where you started, at least in terms of levels
of alertness and calmness, well, then you would just keep
your inhales and your exhales relatively balanced in terms of duration. Now, the introduction of
things like breath holds with box breathing or Wim Hof breathing, typically, it's 25 or
30 deep inhale, exhales, deep inhale, exhales, and
then exhale all your air, hold your breath for 15 to 60 seconds, and then repeat and so on,
sometimes some inhales and holds. Well, that's a whole business into itself. But for sake of meditation,
the key thing to understand is that if you are going to do a complicated breathing practice, it will, by design, by necessity, shift much of your attention
to the breathing practice, especially if it's not cyclic, if it's not inhales follow exhales. Cyclic breathing is where
inhales always follow exhales, follow inhales, follow exhales. It actually relies on
a specific brain center called the pre-Botzinger complex discovered by Jack Feldman at UCLA. He was a guest on this podcast previously. However, if you are
doubling up on your inhale, so two inhales [inhaling],
and then an exhale [exhales], a pattern of breathing my laboratory has studied extensively, well, then that relies on
a different brain center, the parafacial nucleus. The point is that if you are
engaging in noncyclic breathing or you are deliberately
emphasizing inhales or exhales or the vigor of inhales
and exhales, et cetera, well, then some portion of
your attention will be devoted to making sure that you follow
that breathing practice. We are very good at going into
cyclic breathing practices by default, and our attention
can drift to other things. Interoceptive or exteroceptive,
it doesn't matter, we can just drift into, you
know, how our body feels or something we see or hear
in the room, et cetera. When we are focused on our breathing and the breathing pattern is noncyclic or complex in some way in that it involves
deliberate voluntary commands, again, from those so-called
top-down mechanisms of the prefrontal cortex, well, that, by design,
requires some portion, often a significant
portion of our attention to be devoted to the
breathing practice itself. So what does this mean? This means that breathwork itself can be a form of meditation, and meditation can involve breathwork, but one should know that the
more deliberate and unnatural that pattern of breathing is, the less you will be able
to focus on other things. Now, this isn't necessarily a bad thing. You can actually leverage this. So for instance, if you are somebody who's very much caught in your own head, right, we talked about this earlier, or you're in a moment where
you're really stuck in your head and you want to get out of your head, well, then that meditation
practice that you do really should be focused
on exteroceptive bias, you should really focus on
something external to you, and I would encourage you to use a natural cyclic
pattern of breathing where inhales follow exhales
follow inhales follow exhales. If, however, you are finding that you're sort of
caught in the landscape of things happening around you and you want to ground yourself,
as it's sometimes called... That's a loose language,
not a scientific language. I know there's this practice of grounding, and that's a whole thing. People are always writing to me, "Is grounding a real thing,
walking barefoot on the Earth and magnetic fields, you know,
and gravitational fields?" Well, gravity's real, but, you know, grounding, there isn't a lot of
science for it, to be frank. It does feel nice to walk
on the ground, however. But if you are somebody
who's kind of feeling pulled out of yourself
a lot or in a moment and you want to bring your
awareness into your body and sort of calm down, well, then I would encourage you to, yes, use a deliberate,
somewhat unnatural or non-default pattern of breathing, which, by definition, will force you to attend to what's
going on interoceptively. Again, I'm not aware of any place that this has been discussed
in detail such as this before. If there is a research literature on this, please let me know. My laboratory has been
working on this extensively. I'm always looking for new
colleagues and collaborators. We, meaning Dr. David Spiegel
who's an expert in hypnosis, again, who's been a guest
on the Huberman Lab podcast and my colleague at Stanford Psychiatry. In fact, he's our associate
chair of psychiatry, world expert in hypnosis, he's
been on this podcast before, we have an active research
program focused on these issues. We are very much of the belief that a breathwork practice
itself can be meditative, a meditation practice
can include breathing, but the more that that meditative practice focuses on the breathing itself, the more interoceptive-biased it will be. Now, it's very important to understand that an interoceptive-biased
breathwork practice will have a specific effect, which is to make you more
interoceptively aware. And if you think back to
earlier in the episode, for many people, that
will be a wonderful thing and something that they
are actively seeking or ought to seek because it can help people gain awareness, for instance, you know,
if they're stressed and they're not realizing
it till the end of the day, they're just exhausted, more interoceptive
awareness throughout the day can be very beneficial. If, however, you are somebody who is overly focused on
your bodily sensations, well, then more exteroception
awareness is important. And this brings us to a yet larger theme but a theme that I think really emphasizes what particular types
of meditative practices are going to be best for certain people, especially people who are using meditation to combat certain challenges, in particular, mood-based challenges or sleep-based challenges
or focus-based challenges. I haven't listed off all the positive benefits of
meditation yet in this episode, but they are many, many, many. In fact, there are now tens of thousands of scientific studies
showing, for instance, there are known benefits
of doing meditation for enhancing sleep, there are known benefits of
a regular meditation practice for enhancing focus, there are known benefits of
a regular meditation practice for reducing inflammatory cytokines, even improving outcomes in cancer, reducing pain, improving mood, reducing the symptoms of ADHD
and clinically diagnosed HD and on and on and on. And, again, rather than focus on all those beautiful studies today which all basically point to the fact that some meditation
practice done regularly, even if it's very brief, has tremendous, even outsized
benefits on our health even relative to some drug
treatments, that's been shown. Rather than focus on all
that, I've been more focused on what sorts of brain
and body changes occur when we do a meditation practice and, perhaps more importantly, what really constitutes
a meditation practice. We have this thing about
a continuum of perception. We also now are talking about breathing. Well, there's another component
that I'd like to raise now, which we could say is
the third major component if the first one that I raised was interoceptive versus
exteroceptive bias or continuum, the second being breathing, is it going to be default
or deliberate breathing? Is it going to be natural
cadence or unnatural cadence? Again, no right or wrong, it just depends on what your goal is. There's a third component. This is a component, again, that hasn't really been
formalized in the literature but that Dr. Spiegel and I
are working hard to formalize through some research and
through an upcoming review that we will provide
links to once it's out, and that's a separate continuum
which is the continuum between interoception and dissociation. So now all of you know
what interoception is, but most people probably don't know or don't realize what dissociation is. Often we hear about dissociation, sometimes called disassociation. Some people pronounce it
dissociation. Guess what? Despite being corrected many times for each of those pronunciations, I checked with my colleagues who are experts in
dissociation or disassociation, and guess what? They're the same thing.
Tomato, tomato, potato, potato. So I'm going to say dissociation. Some people will say
disassociation, like I disassociate. Other people will say I dissociate, okay? Both of those refer to
essentially the same thing. Dissociation is often talked about in the context of a negative event. And indeed, dissociation is unfortunately, or, I should say, is adaptively associated with traumatic events. In particular, violent or sexual
trauma, people will report feeling out of body or
out of the experience during the experience or during a recollection
of the experience. Dissociation has also been described in terms of people who are
in a traumatic accident or they see someone killed
right in front of them. First responders will
talk about dissociating when they arrive on a scene. I don't want to provide, you
know, gruesome imagery here 'cause I know people can be
pretty sensitive to this, but, you know, showing up
on the scene of a car crash and just seeing carnage or
incredible damage to bodies or, you know, this sort of thing. Dissociation lies at the opposite end of a continuum with interoception. Now, earlier, I said that interoception is on the opposite end of a
continuum with exteroception, but it also is on the opposite end of a continuum with dissociation. We can provide some
better definitions perhaps to make this crystal clear, and here, I'm actually reading
from an upcoming review. I feel comfortable reading from it because I'm an author on the review. But nonetheless, interoception
refers to a process by which your nervous system, meaning your brain and
connections with your body, senses, interprets, integrates,
and regulates signals originating from within the body, and thereby provides a
moment-to-moment mapping of your internal landscape at both a conscious and unconscious level. Okay, that's a lot of words to describe basically the process of perceiving what's happening at the level of the surface
of your skin or inward. Dissociation can be thought of as the opposite of interoception. It's a lack of bodily awareness or a removal of one's conscious experience from one's bodily
experience and awareness. Again, this is most often talked about in the context of something traumatic, but really, if we think about health and mental health and physical health, the optimal place to reside on the continuum between
interoception and dissociation is somewhere in the middle. We don't want to be dissociated
from life's experiences, but we also don't want everything
that happens in the world to profoundly impact our
heart rate and our breathing. We'd be yanked around by every experience. There are instances in
which being yanked around or pulled into an experience is something that we desire and want, like seeing a movie that we want to see or, for instance, clinical
hypnosis or falling in love, wonderful experiences and sometimes also sad experiences, right? Being able to feel one's feelings depending on life's events is important. But being too dissociated
or being too feeling, that is, feeling so much in response to everything that
happens is also problematic. There are certain people, for
instance, that have challenges with what's called narrative distancing. That is, they see someone
in a movie getting hit and they almost flinch as
if they are getting hit. They see someone who's
scared or happy in a movie and they feel scared or happy in a way that seems like
they're along for the ride a little bit too much. This is important
because what it speaks to is the ability for that... Remember way back at the
beginning of the episode, that ACC, that anterior
cingulate cortex and the insula. We've got a prefrontal cortex that can say, hey, let's be rational. That movie, that person
who's happy or sad, that person in your environment
who's breaking down crying, yes, they're sad, it's
important to be sympathetic, maybe even empathic towards them, but let's not get pulled
into the experience so much that we lose ourselves. And then of course there
are areas of your brain that are also leaning on,
and here I'm using metaphor, but they're leaning on the
insula and ACC and saying, hey, there's somebody that
I care about that's upset, I'm also going to be upset, or somebody I care about is happy, I'm also going to be happy, or they're scared so I'm
also going to be scared. So it's a push-pull
between our recognition that we are each distinct entities and also, of course,
the very healthy desire to be attached to others' experiences and the experiences around us. So why am I raising yet
another continuum, right? We already have the one continuum of interoceptive-exteroceptive awareness. Well, if we want to think
about how meditation can serve our mental health
and our ability to focus, there's a very particular mental
model that we can arrive at that incorporates this
interoceptive-dissociative continuum. Again, if you are extremely interoceptive, you're feeling everything in your body, and those feelings in your body nearly completely account
for all of your experience if you're at that far
end of the continuum. On the dissociative end of things, you can see what's going on, you can react to what's going on, but your bodily response to
that is essentially shut down. You could either be paralyzed shut down, so kind of no movement, or you could still be
engaging in behaviors but you're dissociated. Again, sadly, this is often
what victims of trauma report, that they are able to just
go through the motions but just shut off their emotions or their emotions just shut off. They aren't feeling the elevated
heart rate or breathing. Sometimes they can even be quite scared, but they're not even perspiring or showing any signs of autonomic arousal, that is, fright or stress or panic. So let's talk about this model of interoception and dissociation and then a meditative practice that can be used to try and
anchor us at the right location or the healthy location
along that continuum. Let's first imagine the
ideal mental health state. And here, I want to
acknowledge, nobody achieves or at least maintains
this mental health state. I want you to imagine that where you are along this
interoceptive-to-dissociative continuum is like a ball bearing, or you represent a sphere that can roll back and
forth along the continuum. At one end, you have pure interoception, you're just feeling everything. At the other end, you're
completely dissociated. Well, in this one
version of mental health, we take that continuum
and we fold up the sides so that it looks like a V, okay? On one end, you have interoception. On the other end, you have dissociation. I realize a number of
people are listening to this and not watching this on YouTube so they can't see that my hands are now, the heel of my hands are together, the fingers of my hands are
apart so it looks like a V, and you are like a ball bearing. Your state is like a ball
bearing at the base of that. You are in a trench of perfectly balanced
interoception and dissociation, so you can feel things, you can register what's going
on in the outside world, but your feelings are not
overwhelmed or overtaken by what's happening in the outside world. You are in a perfect place of being able to make rational decisions and yet still feel your feelings. Wouldn't that be lovely? Wouldn't that be lovely
if we could be like that whenever we wanted to? And frankly, nobody is
like that all the time. More typically, the model
of mental health and mood and well-being and perception
of self versus others and internal versus external states is one of more of a U, a U shape, where at one end, we have interoception, and at the other end,
we have dissociation, and it's kind of U shaped, and your state is more or
less like a ball bearing at the base of that U that, you know, it gets
pushed from side to side. Maybe, you know, your
heart races a little bit because of something bad or good, and that ball bearing
shifts towards interoception a little bit more and you notice
that your heart is racing. Or perhaps, at any given moment, you know, your mind drifts a little bit while watching a movie or
while talking to your partner or while your child is
complaining about something and you're thinking about something else, and that ball bearing shifts towards the dissociative
state a little bit. That is a mild form of dissociation. And I think most people would agree that being mentally healthy would involve this kind
of U-shaped model as well, where it kind of can shift back and forth, but it's not extreme. You're not going from interoceptive-biased all the way to dissociated
in any kind of extreme way. The ball bearing stays down
near the base of that U. Then, of course, there are states that we all, frankly, go
into from time to time where the continuum of
interoception and dissociation is essentially flat, where you are a ball bearing
at one location or another, depending on whether or
not you're watching a movie that you're very engrossed in or you're in a conversation with or in an activity with your
partner or a friend, et cetera, that has you very engrossed, maybe matching their state, right? There are a number of
states you can imagine where matching one's state
is actually healthy and good, and then there are a number
of conditions in life and situations in life where being matched to
someone else's condition like you're getting yelled at and they're angry so then
you're getting angry, and then pretty soon, you know, you're not in the
best place along that continuum. And I think that for many people, they find themselves somewhere
along that continuum. And a number of practices,
including meditation, including exercise, including
getting a good night's sleep, including therapy, including journaling, including just doing activities like social engagement that you enjoy, are designed to sort of bring up the edges of that flat continuum into
more of a U or concave shape so that that ball bearing, meaning your state of awareness and your state of
feeling your own feelings versus paying attention to
what's going on around you, is somewhere, again,
biased toward the middle. By curling up the edges of
that continuum on either end, it biases that state toward the middle. And then, of course, there's the extreme that I think almost everybody would agree is more or less pathologic, which is one in which that continuum is no longer shaped like
a deep trench like a V, it's not shaped like a U, it's not flat with the
edges curled up a little bit or even flat. It's actually now convex. It looks like a mountain shape, a peak, and that little ball bearing at the top can either drop all the way to one side of pure interoception, just feeling beyond any ability to pay attention to anything else, just feeling one's feelings, being angry, being sad,
or even happy, right? Being so extremely happy or manic that you can't pay attention to the fact that it's totally out of context, right, inappropriate for what's
going on around you, or dropping to the other
side of the continuum where you're so dissociated that you're not engaged with
what's going around you. You're truly, quote, unquote, checked out. That shape is one that I
think almost all clinicians, if not all clinicians, and most people would say is pathologic because you are either
completely checked out or you are completely
absorbed in what's going on within you or around you. That mental model that I just created is a simple mental model. It is by no means exhaustive, but it does incorporate a
lot of what we think about when we think about mental health and we talk about the ability
to be mentally stable, to feel one's feelings, but to still be actively engaged in what's happening around us. And again, it's a continuum that spans from interoceptive
awareness to dissociation where the extremes are pathologic and somewhere in the middle is healthier, and then there are practices that bias us toward being in the middle by default. What are those practices? Well, we know for sure that being sleep deprived, for instance, tends to take us away
from that trench shape or U-shape continuum
or even flat continuum and starts to make that
continuum more convex. It tends to make us either feel like we're completely
checked out and exhausted or that we are completely labile, we are yanked around by whatever
experience is happening, we are just not able to manage. So sleep is, as I always say, the fundamental or foundational layer of mental health, physical
health, and performance because it tends to put
us in a healthier place. That is, when we're getting enough quality sleep consistently, it tends to put us in the
middle of that continuum. Sleep deprivation does
exactly the opposite. It pulls us apart. And when I say pulls us
apart, that's not a real term. What it does is it tends
to make that continuum less concave, right, less bowl shaped, and more convex, more hill shaped, if not a peak mountain shape where it drops us to
one side or the other. In addition, a meditative
practice done regularly, because it can allow us to
become more interoceptively aware or it can allow us to become
more exteroceptively aware, which is really just another
form of dissociation, again, dissociation isn't always bad provided it's not at the extreme, a meditative practice
can actually teach us to deliberately move along this continuum. So this is something, again, that hasn't been discussed a
whole lot in the literature. It's been discussed, I should say, in pieces in different literatures. If you look in the clinical
psychiatry literature, there's a wonderful collection
of studies and reviews that will say that interoceptive
awareness is terrific except for the person that is so aware of their
internal functioning that they are not able
to engage in the world. Similarly, you'll find
a beautiful literature, research and clinical literature, that will say that
dissociation is terrible in the case of trauma. In fact, it can put people in positions of repeating a behavior over and over that's damaging to them, but because they can disengage or they're dissociated from it that they continue the behavior, or dissociation can be very
adaptive and beneficial if it allows people, for instance, to create
some narrative distancing so they're not getting
pulled into every argument, or if someone screams at them, they don't necessarily
think that it's their fault. They are able to say, "Hey, wait," you know, use their
prefrontal cortex and say, "Hey, wait, like, just
because you're upset does not mean that I did something wrong. Let's look at the evidence
rationally." Okay? So in thinking about the positive effects of meditation on mood, there are two aspects that are important. The first one we talked about earlier, which is being present to one's experience correlates with increased happiness. Having your mind wander, having your default mode
network be one of mind wandering actually is correlated
with being more unhappy. That was the earlier study
that we talked about, that study published in "Science." Now, of course, meditation
can make us more present, but if we do not pay attention to whether or not we are
becoming more present to interoception or exteroception, that is, to interoception or dissociation, and we don't pay attention
to whether or not our bias is one of dissociation
versus interoception, we don't know where we
are on the continuum, well, then the meditation actually can make things
worse, not better. In other words, if you're somebody who has a tremendous amount
of interoceptive awareness, well, then meditating
on your internal state may not be good, and actually, there's some evidence that it may actually be bad. I'll give you one little tiny example. I've talked about this
previously on the podcast, but in that very study
from Wendy Suzuki's lab showing that 13-minute-a-day meditation is beneficial for focus, mood, et cetera, it's also very clear that
for a number of people that do that typical third eye meditation for 13 minutes a day, if they do that too close to sleep or when they want to go to sleep, they have a hard time falling asleep, which makes perfect sense because they are becoming
more interoceptively aware, they are ramping up their level of focus. A meditation practice typically is a focus and refocus practice, and falling asleep involves turning off your thoughts and your focus and focusing purely on sensation, and then your thoughts kind of fragment and you drift off to sleep. This is why I'm a big fan of using non-sleep deep
rest or yoga nidra. We will provide links
to non-sleep deep rest and yoga nidra protocols. I've talked about them
on the podcast before, but those protocols are
not meditation per se. They tend to have people defocus, they are anti-focus practices, whereas meditation tends
to be a focusing practice. Along those lines, a meditation practice that is one that is
exteroceptively biased, where you focus on things
that are outside your body, can be wonderful for somebody who tends to focus too much
on their inner landscape and their inner narrative, et cetera, it can help get them out
of their head and body, which can be very beneficial. But for people that are not
in touch with their emotions, aren't in touch with how they feel, it actually can drive
them down the exact path that's wrong for them. So today's discussion is about meditation, and we want to make sure that we are parsing
meditation in a rational way that matches the neural circuitry involved and, more importantly, for
sake of practical purposes, that you are asking
yourselves the right question. Are you interoceptively
or exteroceptively biased? Do you tend to dissociate, or do you tend to sort of feel everything in a big way, right? I've heard this term of, you
know, hypersensitive people or things that sort, and, you know, some of
those are clinical terms, some of them are not. But you need to assess this, and you also need to assess where you happen to be at on a given day, which will be dictated, of
course, by how well you slept, life experience, et cetera. So this interoceptive-to-dissociative
continuum is one that you need to address prior to any meditative practice. And, again, the solution
or the answer of what to do in response to your answer of whether or not you
are more inward focused or outward focused, again, is very simple. Just do the opposite of
where your bias lies. That is, if you're tilted
towards interoception, do an exteroceptive focused practice. If you are more dissociative and you're... That sounds sort of pejorative,
it sounds bad, right? But, again, if you are somebody who is more focused on
events outside your body and you want to gain more
interoceptive awareness and feeling state, if you will, well, then you want to do a practice that's third eye center
practice or breathing focused. One of the reasons that
many people meditate is that they've heard before
or they've experienced that meditation can replace sleep or can reduce one's overall sleep need. So that's an interesting set of questions, and it's one that I
dove into the literature to pursue an answer to, and I came up with an answer that was frankly a little bit
complicated on the face of it but boils down to some
very simple protocols that I think any and
all of us can leverage in order to sleep better and maybe even reduce
the total amount of sleep that we need, something that I think
most people would want. You know, I realize that we all probably should enjoy
sleeping, I certainly do, but that it's hard to get enough sleep, and wouldn't it be wonderful, for instance, to be able to
get by on a little less sleep and still feel alert and rested? First of all, I want to
point to the recent study, and, again, this is one
that I've raised a few times and we'll post a link to it, entitled Brief, daily meditation
enhances attention, memory, mood, and emotion regulation
in non-experienced meditators. This is the work, again, from Wendy Suzuki who was a guest on the
Huberman Lab podcast, who is now the Dean of Arts and Sciences at New York University and has run a laboratory focused
on memory for a long time, is a terrific neuroscientist
and researcher and teacher, et cetera, and was a terrific guest on the podcast. I keep returning to this paper because they used so many
measures, they were very thorough, and the results were really interesting. Again, this is the 13-minute-a-day guided meditation session. I should just mention that the
control group in this study listened to a podcast for 13 minutes that did not improve
attention, memory, mood, emotion regulation, et cetera,
as much as meditation did, which is not to say that
podcasts aren't useful. I won't mention which podcast they used. Fortunately, it was not
the Huberman Lab podcast, which I like to think at
least increases understanding of certain key concepts of
science and science-based tools. You're welcome to look at the paper and see which podcast they used. It's a quite well-known podcast, which is an interesting podcast, but it didn't change the
brain in any fundamental way in this 13-minute session, whereas 13 minutes of
daily meditation did. And, again, something I mentioned earlier but very important to reemphasize now is that they mentioned that if people in the experiment meditated too close to bedtime, they had trouble sleeping,
again, which makes sense because meditation, at least
in its most common form, in the form used in this paper, is a focusing and refocusing exercise. Falling asleep involves focusing less. There are other studies, however, that have shown, or that asserted, rather, that doing two 20-minute
sessions per day of meditation can reduce the need for sleep. Those results are debated. First of all, understanding
what sleep need is is very individual, and determining what people can manage on, meaning some people can manage to get by with six hours of sleep but
would do better with eight, some people would actually
manage probably better in terms of focusing and alertness if they slept a little bit less because they might be waking up midway through a sleep cycle. If you want to learn more about this, you can check out any one
of three different episodes that we've done. One is Master Your Sleep. You can find that at hubermanlab.com. Everything is timestamped in that episode. The other is Perfect Your Sleep. And then, of course, we've
done episodes on sleep with expert guests like Dr.
Matthew Walker from UC Berkeley. All of those can be found at
hubermanlab.com in all formats, they're all timestamped. With that said, this
assertion that has been made many times over and certainly
in the popular press that regular meditation can
reduce one's overall sleep need is controversial for the following reason. Some groups find that
indeed that is the case, and the interpretation is
that the stress reduction that's brought about by
regular meditative practice, and in this case, very regular, it tends to be one or, more
typically, two 20-minute-per-day meditation sessions. That's quite a lot, I
think, for most people. I mean, if you think about 40 minutes, isn't that much time overall, but very few people will
stick to that twice a day, 20-minute meditation
practice very consistently. Well, the idea is that
the stress reduction, which is clear and not debated, brought about by that type
of meditation practice is good at offsetting some
of the cortisol increases associated with reduced sleep and leading people to be able to function cognitively and physically
better on reduced sleep than they would had they not been doing
the meditation practice. So the simple way of putting this is that if people meditate regularly, that's reducing stress. The reduction in stress
is reducing cortisol. Again, cortisol is healthy, but it should be restricted
to early part of the day. You don't want too many peaks in cortisol, especially not late in the day. By meditating, you get the healthy pattern of cortisol release, you sort of inoculate yourself somewhat against the unhealthy
pattern of cortisol release, and as a consequence, either the sleep that people get is deeper and/or the total amount of
sleep that they need is reduced. Now, a lot of people took that result and interpreted it as saying, well, if you can't sleep,
then you can just meditate. So one night, you don't sleep
or you have trouble sleeping, you just meditate the next
day and you'll be fine. Well, certainly that is not
supported by the literature. However, there is a practice, and, again, it's one
that I've talked about on this podcast many times before, but if you haven't heard me talk about it, there's a practice called yoga nidra, which literally means yoga sleep. It is a practice of doing not
so much a focused meditation, but more of a body scan focusing on the sensation of the body and actually trying to turn
off that prefrontal cortex or reduce its activity. Yoga nidra scripts can be
found on YouTube and elsewhere. They are paralleled by a similar practice that I've talked a lot about called NSDR, or non-sleep deep rest. I put one out into the world, a short one that's 10 minutes long. You can just simply go to YouTube and put in NSDR and my
last name, Huberman, and there's one there. Again, all of this is
completely zero-cost. Yoga nidra and NSDR have been shown in a fair number of studies, not as many as been done
on traditional meditation, or I should say third
eye centered meditation or mindfulness meditation, but have been shown to replenish levels of certain neuromodulators like dopamine and reduce cortisol,
reduce a stress hormone at least as much and, by
my read of the literature, significantly more than
with traditional meditation. And there's a nice paper that we will provide a
link to which is entitled Yoga nidra practice shows
improvement in sleep in patients with chronic insomnia: A randomized control trial. Basically, this study looks
at, as the title suggests, people with chronic insomnia, although the results certainly carry over or would carry over for people
who don't have insomnia. The key result, I believe, in this paper, although there are many, is that, quote, "Salivary cortisol reduced
statistically significantly after yoga nidra." What do I mean by that? There was a statistically
significant reduction in cortisol levels, the stress hormone, immediately after the yoga nidra practice that we believe would be paralleled by a very similar if not
equivalent practice of NSDR. NSDR is a lot like yoga nidra but removes a lot of the kind of, let's just call it the
sort of mystical language and the intentions. It focuses more on the
physiology and the body scans. You know, I want to
acknowledge that yoga nidra has been around for thousands of years and was certainly there before NSDR. I also want to acknowledge that, and this was brought up
also in "Altered Traits," that sometimes language can be a barrier toward people embracing practices. In fact, this was
recognized by Jon Kabat-Zinn when he created what he called mindfulness-based stress
reduction practices, or MBSR, which was simply mindfulness
meditation to reduce stress, but he called it MBSR,
mindfulness-based stress reduction, as a way to bring it into the clinics that would otherwise perhaps be averse to something called
mindfulness meditation. Again, this gets more to the sociology and the cultural aspects than it does to any specific utility of one practice versus another. Here's the takeaway point. If you want to get better at
falling and staying asleep or falling back asleep if you wake up in the middle of the night or if you are generally
challenged with sleep issues, an excellent behavioral practice for which there are terrific data, meaning data that show that
a stress hormone, cortisol, can be significantly reduced as well as certain
neurotransmitters can be replenished as well as, and this is key
and covered in this paper that I've mentioned a few
moments ago on yoga nidra, that the total amount
of sleep that you need can be reduced, at least somewhat, well, then yoga nidra or an NSDR practice done, frankly, any time of
day is going to be beneficial. Whereas if your goal, I believe, is to increase your ability to
focus, to improve your mood, and, perhaps most importantly, to be able to maneuver
yourself in a deliberate way along that interoceptive-exteroceptive or interoceptive-dissociative continuum that we've talked about so much, and to really shift your
default mode network from one of being a mind wanderer to somebody who can focus
and who frankly is happier, well, then a more traditional third eye center type meditation or a more traditional
exteroceptive-focused meditation would be beneficial. Again, which one of those you
choose, either focusing inward or focusing on a point outside of you, again, should be dictated by whether or not you tend
to be interoceptively biased or exteroceptively biased. But if you want to get better at sleeping, you want to get better at falling asleep, and you want to replace
sleep that you've lost, I put that in quotes so that my colleagues like Matthew Walker don't come after me with... What would you come after me with, Matt? Probably with an alarm clock and, I don't know, blankets and a pillow or something of that sort. In all seriousness, it's very clear that replacing
sleep that we've lost is an area of research that's
still active and ongoing, but NSDR and yoga nidra
are very promising, if not downright useful, for replacing sleep that you've lost. Certainly the small amount
of data that exists now point to the fact that they are, not the least of which
is a beautiful study published out of Scandinavia showing that a 30-minute
yoga nidra aka NSDR practice can replenish levels of dopamine, which puts people in a position to be more action-oriented
and focused, et cetera, when they come out of the yoga nidra, so certainly a very useful practice. It's a form of meditation, we
could call it meditation-ish, but yoga nidra and NSDR are not typically what people think about when we talk about meditation. Of course, this is an
episode about meditation. The reason I bring up yoga nidra and NSDR is that many people meditate
to enhance their sleep ability and to reduce their total
amount of sleep need. It appears that meditation is
probably not ideal for that in comparison to yoga nidra and NSDR, but meditation is
excellent, if not superb, for adjusting the default mode network toward more happiness by
being more mindful and present and for placing oneself
in that healthy model of interoceptive-dissociative continuum. So we've covered a lot of information, and I like to think that I've given you some key decisions to make in developing a meditative practice. The most important one, of course, being what will you do regularly? And maybe you're somebody who
just answers that question by saying, "Look, I'm not
going to meditate regularly. I just want to do the thing that's going to allow me to
feel rested when I'm tired and is going to allow me
to adjust my state of mind when I'm not where I want
to be for whatever reason, too anxious or too exhausted, et cetera." And for those people, I would say a practice
like NSDR or yoga nidra will be immensely beneficial, as will a more traditional
form of meditation. I also want to just remind everybody that an app that guides meditation, also with some information
and some intention setting, such as the Waking Up app from Sam Harris can be immensely beneficial. I've certainly found it to be beneficial. I know millions of other
people have as well, so I encourage you to check that out. We've talked about
determining where you are on these continuums of
interoception and exteroception in order to dictate what particular type of meditation practice you
should do in a given moment, whether or not you
should focus your vision inward with eyes closed or focus your vision and
your attention outward being a key component, whether or not you should
do cyclic breathing, which will allow your focus
to be off your breathing somewhat easier than if you
do non-cyclic breathing, if you're doubling up
on inhales or exhales, whether or not your breathing
is going to be natural or not. And, of course, you need to determine whether or not your meditation practice is designed to enhance your
level of focus or to relax you. I would say that if it's designed to enhance your level of focus, that doesn't necessarily mean
that it won't be relaxing. You could do slow cadence breathing and third eye meditation,
it could be very relaxing, and yet it's a focus and refocus practice, whereas something like yoga nidra and NSDR is going to be more along the lines of replenishing yourself,
replacing sleep that you've lost, or maybe even reducing your sleep need. On previous podcasts, I've
talked about hypnosis, and particularly the episode
with Dr. David Spiegel, our associate chair of psychiatry. I don't want to get into hypnosis now, but just understand that
hypnosis is distinct from breathwork, from
yoga nidra, from NSDR, and from meditation even though it includes
some of those components like focusing your attention, it involves actually directing
your visual attention outward then inward to
go into the hypnosis, it involves some breathing
of a particular kind, it involves a specific imagery, et cetera. But hypnosis is distinct because
hypnosis is really designed to fix or address a specific problem, whereas meditation, NSDR,
yoga nidra, et cetera, typically are not. They can help fix problems such as anxiety, sleep issues, et cetera, but they generally are not directed toward a particular line of thinking. They can be, but typically they are not. Whereas hypnosis almost always, especially in the clinical
context, not stage hypnosis, but the clinical context for
which there's a lot of research to show it can, for instance,
help with quitting smoking, literally a quadrupling
of the effectiveness for smoking cessation with
something like the Reveri app than if people just try and go cold turkey or for reducing insomnia
or for reducing pain or for any number of things,
including trauma, et cetera, hypnosis is really great at
dealing with specific issues and problems and tackling those. Meditation tends to be
focused on other things, no pun intended. I'm guessing some of you are probably wondering where to start or, if you're already an avid meditator, where to go with all this information. For that reason, I just wanted to offer you a
particular form of meditation that incorporates all of the features that I've talked about up until now in a single meditation practice, and it's a meditation practice that, for lack of a
better name, I called STB, or Space-Time Bridging. And the time component has to
do with a very simple fact, which is when we focus our attention, visual attention or otherwise, on things close to or within our body, we tend to be fine slicing time. You could sort of think of your breath as more or less the second hands
on your clock of existence, whereas when we tend to focus
on things far away from us, we tend to parse or carve
up time within bigger bins. If you've ever seen a
airplane flying at a distance, it looks like it's
moving very, very slowly. If you were right up
next to that airplane, it's probably going 500
or 600 miles an hour, it would go by very quickly. This is not a coincidence. Believe it or not, how
you slice the time domain of your life and your experience has everything to do with your vision, and the closer things are, the more finely you slice up time. The more closely your attention
is placed on yourself, the more closely you slice up time. If you focus your visual
attention very far or you think about the other side of the world, for instance,
and you envision that, well, then you're actually
slicing time more broadly. Hopefully that makes sense. Fine slicing would be like
slow motion, higher frame rate. Looking in the distance, you're actually taking bigger time bins. So even though things look like
they're moving more slowly, it's because your fidelity, your precision of measuring
time is actually not as good. It's as if you only have
the hours hand on the clock so it seems like it moves very slowly. Hopefully that makes sense to you. So there's a meditation practice that I call Space-Time Bridging that incorporates everything
that I've talked about today. It balances interoception
and exteroception, it balances interoception
and dissociation, and it crosses the various time domains that the brain can encompass using vision. And it's a very simple meditation, it's one that I've been doing for years, and it's one that we're
starting to do some research on, but I'm just going to share with you because I think it's actually quite fun and can be quite informative. In fact, people have told me that it can even lead to
some interesting insights both during the meditation
and outside the meditation. It's very simple, what you do, ideally you would do this
outside or at a window, but what you do is you
essentially close your eyes. I'm not going to do this now, I'm not going to close my
eyes and do the meditation, but I'll describe it. You close your eyes and
you focus your attention either on your third eye
center or your breathing, and you try and put 100% of
your perceptual awareness onto your breathing or
your third eye center for the duration of three breaths, okay? So you're 100% or trying to
be 100% in interoception. Then you open your eyes, you focus on the surface
of your body someplace. I find that holding out my
hand at sort of arm's distance and focusing on the palm of my hand and focusing there visually, so I'm splitting my attention
now between my hand, and I'm also going to pay
attention to my breath for the duration of three
full inhales and exhales while also focusing on my hand, so you're splitting
interoception and exteroception as best you can, about 50/50. Then you subsequently
look at some location in your immediate environment,
maybe 10, 15 feet away, and you focus your
attention on that location while also splitting your attention so that you're still paying
attention to your breathing, you do that for the
duration of three breaths, but now you are in
exteroception and interoception. Then you focus your attention
at some distance further away, maybe the furthest distance you can see. Now, this is why it's
useful to do out of a window or on a balcony or outdoors. You focus on the furthest
point, maybe a horizon, some furthest point for the
duration of three breaths while also paying attention
to your breathing, and sort of imagine a
bridge between the two if you find it to be
challenging to focus on both. And then, and this is where
it can be a little tricky, but then what you actually
focus on is the fact, and this is not an imaginary thing, this is a fact that you are a tiny spec on this big ball that's
floating out in space, right? The Earth that's floating out in space. And you try and focus
on your three breaths while also acknowledging that you are a small body, literally, on this very seemingly
large body, the Earth, but that's floating in
a much larger, larger, expansive place, the universe, and you do that for three breaths. And then you close your eyes and you go right back into interoception, and you do that for three breaths. You focus on your interoception
for three breaths. And you might want to march
through these different locations a few times or back and forth if you like, but typically, I will
just do it for one segment at pure interoception, palm of hand, some distance
in front of me, horizon, whole globe, universe thing,
back into body, et cetera. Why is this useful? Why
would this be useful? Is it at all interesting, or
is this just some crazy idea? Well, the reason it's useful, I believe, is that it has you deliberately
step your awareness, your perception through every position along that
interoceptive-exteroceptive continuum. Now, I did say to remain connected to, as they'll say in the yoga classes, aware of, I guess would be the more scientific way to state it, aware of one's breath, but if you wanted, you could actually try
and put your awareness completely outside yourself, but most people will find
that challenging to do if they're already paying
attention to their breath. It's just hard to do, so I find it easier to
just split my awareness from interoception to exteroception. But by stepping through
these different locations and then deliberately
placing your perception, your awareness back
into pure interoception, what you do is you essentially
are practicing or exercising this incredible ability
that the human mind has to deliberately place your
perception at specific locations along the interoceptive-exteroceptive
continuum. And I think this is very useful because many of us, including myself, tend to get locked at one
location along that continuum. For instance, if you're
scrolling your phone for a long period of time, you may forget about
your bodily sensations, but you generally forget
about other things going on in the world. Or if you're very focused
on things out in the world, you oftentimes can forget
about your internal sensations and what's going on internally. And being functional in work,
in life, in relationship, and in all aspects, including
your ability to fall asleep, involves stepping yourself
along these different locations, which, again, are not
just physical locations of third eye center or your breathing or your hand or horizon. Those are just stations within space. But remember, each one of those, just by way of how your visual
system and the time domain are interlocked with one another, sets your mind in a
particular time domain. And so much of what involves
being a functional human being involves dynamically
adjusting our attention from what we are doing on our computer to a question somebody
asks and then back again, or from text messaging to listening to a lecture or a podcast or from listening to a lecture or podcast and then going back into
a mode of commuting, but making that commute either relaxing or maybe do work on your commute or connect with family
or friends, et cetera. So much of the fatigue of life and the, I should say,
the maladaptive behaviors and emotions that show up in life are really not about any
set of behaviors or emotions being wrong or right, but rather inappropriately matched to the space-time domain that we're in, which, again, is just fancy nerd speak for saying being present and being mindful is a wonderful byproduct
of a meditation practice, but it is but one of those stations along that space-time continuum. The key element here is to step yourself through a practice deliberately so that you are flexibly
and dynamically able to engage in conversation,
then disengage and focus, or focus and then disengage
from the work you're focusing on and actually have a
conversation or be in the world and move out of that
interoceptive awareness to one in which you
are dynamically engaged with the things around you. I realize this might
sound a little bit vague. For that reason, I encourage you not to
think about it too much, but rather to try the practice,
see if it works for you. If it doesn't, that's fine. I think it is a good one for people that find that a third eye center or breathing-focused
interoceptive meditation might be enjoyable to them
or very beneficial to them, but they might want to try something new, and other people who might find that that tends to put them
too much in their own head. I think it also ought to
be very useful for people that tend to be overly exteroceptive, more on the dissociative
end of the continuum, and need to bring in a bit more
of interoceptive awareness, but either can't do that or
are uncomfortable doing that because they're simply not interested in or comfortable with feeling so
much of their internal state because that can either be overwhelming or that's just simply not
the way they want to feel. Now, as we round up, I
do want to acknowledge that there are an enormous
number of rooms within the house, or rather, I should say, within the castle that is meditation, including, for instance,
intention setting and mantras and an enormous number
of different features of meditation practices that we simply did not
have time to go into and/or for which the research on is not completely ironed out yet. And for that reason, in future episodes in not long from now, I'm going to be sitting down
with experts in meditation that include neuroscientists
and clinicians, but other experts in meditation that certainly are versed in those topics, and where they can't point
to specific research studies can certainly point us
toward the utility of things like mantras and intentions as they relate to getting the most out
of a meditative practice, so I eagerly await those conversations, and I hope you will join
me for those as well. If you're learning from and
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practice of meditation. And last, but certainly not least, thank you for your interest in science. [MUSIC PLAYING]