Video summary
Andrew Huberman explains that neural plasticity, the nervous system's ability to change in response to experience, is a fundamental biological feature available throughout life, though it operates differently depending on age and context. While infants are primed for learning through passive exposure as their crude connections refine into precise circuits, adults over 25 cannot simply learn new things by accident; they must engage specific processes to alter the brain's "superhighways." Contrary to popular belief that exercise or daily experiences automatically generate new neurons after puberty, Huberman clarifies that while we do not add significant numbers of new cells in adulthood, existing connections can still be strengthened or weakened. This change is most evident when sensory inputs are altered; for instance, the visual cortex of a person blind from birth reorganizes to process hearing and touch with high acuity, demonstrating that the neocortex acts as a customized map of individual experience rather than a static structure. However, this plasticity does not occur merely through exposure but requires specific neurochemical conditions involving three key components: epinephrine (adrenaline), acetylcholine from two distinct brainstem sources, and alertness. Epinephrine is released by the locus coeruleus when we are alert or stressed, while acetylcholine acts as a spotlight to filter sensory input in the thalamus, allowing only one signal through amidst noise. Huberman emphasizes that without this combination of chemicals—triggered by attention rather than just action—the brain will not change. He debunks the myth that every experience alters the adult brain equally, citing experiments by Greg Recanzone and Mike Merzenich where subjects could rapidly adapt their tactile maps to detect minute changes in a spinning drum only when they paid intense, selective attention to those specific bumps while ignoring auditory cues. To harness these mechanisms for learning or behavior change, Huberman outlines practical protocols that leverage the brain's natural architecture. The first step is establishing alertness through sleep mastery and motivation derived from love, fear, shame, or accountability, as all emotional states can trigger epinephrine release. Once alert, individuals must practice "visual focus" to induce mental concentration; by narrowing their gaze onto a small point in space (the soda straw view), the brain activates neurons that release norepinephrine and acetylcholine at relevant sites. This visual anchoring is crucial because mental attention follows visual focus, meaning that struggling readers or listeners can improve cognitive depth by physically restricting their field of vision to increase resolution on a specific target. For auditory learning, closing the eyes helps create a cone of auditory attention without competing visual input taking over processing resources. The duration and timing of these focused efforts are governed by ultradian cycles lasting approximately 90 minutes. Huberman advises that optimal learning bouts should align with these natural rhythms, allowing for warm-up periods at the start and end while maintaining peak focus during the middle hour. Crucially, neural plasticity does not occur during wakefulness but is consolidated during sleep; if deep sleep following a focused session is poor or absent, the strengthening of synapses may be compromised unless supplemented by non-sleep deep rest (NSDR) protocols like yoga nidra or brief naps. These NSDR sessions allow the mind to drift and organize thoughts after deliberate effort, accelerating learning rates even without full nocturnal sleep cycles. Ultimately, mastering one's ability to focus visually for 90-minute intervals followed by periods of disengagement ensures that new skills become permanent unless actively unlearned through subsequent processes.
Read the full video transcript
Welcome to Huberman Lab Essentials,
where we revisit past episodes for the
most potent and actionable science-based
tools for mental health, physical
health, and performance.
My name is Andrew Huberman and I'm a
professor of neurobiology and
ophthalmology at Stanford School of
Medicine. Today we're talking about
neural plasticity, which is this
incredible feature of our nervous
systems that allows it to change in
response to experience.
Neural plasticity is arguably one of the
most important aspects of our biology.
It holds the promise for each and all of
us to think differently,
to learn new things, to forget painful
experiences,
and to essentially adapt to anything
that life brings us by becoming better.
So, let's get started. Most people are
familiar with the word neural
plasticity, which is the brain and
nervous system's ability to change
itself. All of us were born with a
nervous system that isn't just capable
of change, but was designed to change.
When we enter the world,
our nervous system is primed for
learning.
The brain and nervous system of a baby
is wired very crudely. The connections
are not precise and we can see evidence
of that in the fact that babies are kind
of flopping there like a kind of a
little potato bug with limbs. They can't
really do much in terms of coordinated
movement. They certainly can't speak
and they can't really do anything with
precision. So, I want to you to imagine
in your mind that when you were brought
into this world, you were essentially a
widely connected web of connections that
was really poor at doing any one thing
and that through your experience, what
you were exposed to by your parents or
other caretakers, through your social
interactions, through your thoughts,
through the languages that you learn,
through the places you traveled or
didn't travel, your nervous system
became customized to your unique
experience.
Now, that's true for certain parts of
your brain that are involved in what we
call representations of the outside
world. A lot of your brain is designed
to represent the visual world or
represent the auditory world or
represent the gallery of smells that are
possible in the world.
However, there are aspects of your
nervous system that were designed not to
be plastic. They were wired so that
plasticity or changes in those circuits
is very unlikely. Those circuits include
things like the ones that control your
heartbeat, the ones that control your
breathing, the ones that control your
digestion, and thank goodness that those
circuits were set up that way because
you want those circuits to be extremely
reliable. So, many nervous system
features like digestion and breathing
and heart rate are hard to change.
Other aspects of our nervous system are
actually quite easy to change. And one
of the great gifts of childhood,
adolescence, and young adulthood is that
we can learn through almost passive
experience. We don't have to focus that
hard in order to learn new things. And
then after age 25, if we want to change
those connections, those superhighways
of connectivity, we have to engage in
some very specific processes. And those
processes, as we'll soon learn, are
gated, meaning you can't just decide to
change your brain. You actually have to
go through a series of steps to change
your internal state in ways that will
allow you to change your brain. Many of
us have been
captivated by the stories in the popular
press about the addition of new neurons.
This idea, oh, if you go running or you
exercise, your brain actually makes new
neurons.
Well, I'm going to give you the bad
news, which is that
after puberty, the human brain and
nervous system adds very few, if any,
new neurons. So, even though we can't
add new neurons throughout our lifespan,
at least not in
very great numbers.
It's clear that we can change our
nervous system, that the nervous system
is available for change, that if we
create the right set of circumstances in
our brain, chemical circumstances, and
if we create the right environmental
circumstances around us, our nervous
system will shift into a mode in which
change isn't just possible, but it's
probable. As I mentioned before,
the hallmark of the child nervous system
is change. It wants to change. One of
the ways in which we can all get
plasticity at any stage throughout the
lifespan is through deficits and
impairments in what we call our sensory
apparatus, our eyes, our ears, our nose,
our mouth. In individuals that are blind
from birth, the so-called occipital
cortex, the visual cortex in the back,
becomes overtaken by hearing.
The neurons there will start to respond
to sounds as well as braille touch. And
actually, there's a one particularly
tragic incident where a woman who was
blind since birth, and
because of neuroimaging studies, we knew
her visual cortex was no longer visual,
it was responsible for braille reading
and for hearing,
she had a stroke that actually took out
most of the function of her visual
cortex. So, then she was blind, she
couldn't braille read or hear. She did
recover some aspect of function. Now,
most people, they don't end up in that
highly unfortunate situation. And what
we know is that, for instance,
blind people
who use their visual cortex for braille
reading and for hearing have much better
auditory acuity and touch acuity,
meaning they can sense things with their
fingers and they can sense things with
their hearing that typical sighted folks
wouldn't be able to. In fact, you will
find a much greater incidence of perfect
pitch
in people that are blind. And that tells
us that the brain, and in particular
this area we we the neocortex, which is
the outer part, is really designed to be
a map of our own individual experience.
So, these what I call experiments of of
impairment or loss where somebody is
blind from birth or deaf from birth or
maybe has a limb
development impairment where they they
have a stump instead of an entire limb
with a with a functioning hand,
their brain will represent the body plan
that they have, not some other body
plan.
But, the beauty of the situation is that
the real estate up in the skull, that
neocortex,
the essence of it is to be a customized
map of experience. A few years ago,
I was at a course and a woman came up to
me and she said, "You know, I I wasn't
teaching the course, I was in the
course." And she said, "I just have to
tell you that every time you speak, it
really stresses me out." And I said,
"Well, I've heard that before. But, do
you want to be more specific?" And she
said, "Yeah, your tone of voice reminds
me of somebody that I I had a really
terrible experience with." I said,
"Well, okay, well, I can't change my
voice, but I really appreciate that you
acknowledge that and it also will help
explain why you, you know, seem to
cringe every time I speak." Which I
hadn't noticed until then, but after
that, I did notice. She had a very
immediate and kind of visceral response
to my speech. But, in any event, over
the period of this 2-week course,
she would come back every once in a
while and say, "You know what? I think
just by telling you that your voice was
really difficult for me to listen to,
it's actually becoming more tolerable to
me." And by the end, we actually became
pretty good friends and we're still in
touch. And so, what this says is that
the recognition
of something, whether or not that's an
emotional thing or a desire to learn
something else, is actually the first
step in neural plasticity. Could I get
up out of this chair and walk out of the
door? I don't think about each step that
I'm taking and that's because I learned
how to walk during development. But,
when we decide that we're going to shift
some sort of behavior or some reaction
or some new piece of information that we
want to learn is something that we want
to bring into our consciousness. That
awareness
is a remarkable thing because it cues
the brain
and the rest of the nervous system that
when we engage in those reflexive
actions going forward, that those
reflexive actions are no longer fated to
be reflexive. Now, if this sounds a
little bit abstract, we're going to talk
about protocols for how to do this. But,
the first step in neuroplasticity is
recognizing that you want to change
something. We have to know what it is
exactly that we want to change. Or if we
don't know exactly what it is that we
want to change, we at least have to know
that we want to change something about
some specific experience. Now, there are
specific protocols that science tells us
we have to follow if we want those
changes to occur. What it is is it's our
forebrain, in particular our prefrontal
cortex, signaling
the rest of our nervous system that
something that we're about to do, hear,
feel, or experience is worth paying
attention to. So, we'll pause there and
then I'm going to move forward. One of
the biggest lies in the universe
that seems quite prominent right now is
that every experience you have changes
your brain. People love to say this.
They love to say, "Your brain is going
to be different after this lecture or
that your brain is going to be different
after today's class than it was 2 days
ago." And that's absolutely not true.
The nervous system doesn't just change
because you experience something unless
you're a very young child.
The nervous system changes when certain
neurochemicals are released and allow
whatever neurons are active in the
period in which those chemicals are
swimming around
to strengthen or weaken the connections
of those neurons.
So, when people tell you, "Oh, at the
end of today's lecture or at the end of
something, your brain is going to be
completely different." That's simply not
true. If you're older than 25, your
brain will not change unless there's a
selective shift in your attention or a
selective shift in your experience that
tells the brain
it's time to change.
And those changes occur through
strengthening and weakening of
particular connections, but the
important thing to understand is that if
we want something to change, we really
need to bring an immense amount of
attention to whatever it is that we want
to change. This is very much linked to
the statement I made earlier about the
it all starts with an awareness.
Now, why is that attention important? In
the early 90s, a graduate student by the
name of Greg Recanzone was in the
laboratory of a guy named Mike Merzenich
at UCSF.
And they set out to test this idea that
if one wants to change their brain, they
need to do it early in life because the
adult brain simply isn't plastic. It's
not available for these changes.
And they did a series of absolutely
beautiful experiments.
By now, I think we can say proving
that
the adult brain can change provided
certain conditions are met.
Now, the experiments they did are tough.
They were tough on the experimenter and
they were tough on the subject. I'll
just describe one.
Let's say you were a subject in one of
their experiments. You would come into
the lab and you'd sit down at a table
and they would
record from or image your brain and look
at the representation of your fingers,
the digits as we call them.
And there would be a spinning drum,
literally a like a stone drum in front
of your metal drum that had little
bumps. Some of the bumps were spaced
close together, some of them were spaced
far apart.
And they would do these experiments
where they would expect their subjects
to
press a lever whenever, for instance,
the bumps got closer together or further
apart. And these were very subtle
differences. So, in order to do this,
you really have to pay attention to the
distance between the bumps. And these
were not Braille readers or anyone
skilled in doing these kinds of
experiments.
What they found was that as people paid
more and more attention to the distance
between these bumps, and they would
signal when there was a change by
pressing a lever,
as they did that, there was very rapid
changes, plasticity in the
representation of the fingers.
And it could go in either direction. You
could get people very good at detecting
the distance between
uh bumps that the distance was getting
smaller or the distance was getting
greater.
So, people could get very good at these
tasks that you're kind of hard to
imagine how they would translate to the
real world for a non-Braille reader, but
what it told us is that these maps of
touch were very much available for
plasticity, and these were fully adult
subjects. What it proved is that the
adult brain is very plastic. And they
did some beautiful control experiments
that are important for everyone to
understand, which is that sometimes they
would bring people in and they would
have them touch the
these bumps on this spinning drum, but
they would have the person pay attention
to an auditory cue. Every time a tone
would go off, or there was a shift in
the pitch of that tone, they would have
to signal that. So, the subject thought
they were doing something related to
touch and hearing, and all that showed
was that it wasn't just the mere action
of touching these bumps. They had to pay
attention to the bumps themselves. If
they had were placing their attention on
the auditory cue, on the tone, well,
then there was plasticity in the
auditory portion of the brain, but not
on the touch portion of the brain. And
this really spits in the face of this
thing that you hear so often, which is
every experience that you have is going
to change the way your brain works.
Absolutely not.
The experiences that you pay super
careful attention to
are what open up plasticity, and it
opens up plasticity to that specific
experience. So, the question then is
why?
And Merzenich and his graduate students
and postdocs went on to address this
question of why, and it turns out the
answer is a very straightforward
neurochemical answer. And the first
neurochemical is epinephrine, also
adrenaline.
We call it adrenaline when it's released
from the adrenal glands above our
kidneys. That's in the body. We call it
epinephrine in the brain, but they are
chemically identical substances.
Epinephrine is released from a region in
the brainstem called locus coeruleus.
Epinephrine is released when we pay
attention
and when we are alert.
But the most important thing for getting
plasticity is that there be epinephrine,
which equates to alertness, plus the
release of this neuromodulator
acetylcholine.
Now, acetylcholine is released from two
sites in the brain. One is also in the
brainstem, and it's named different
things in different animals, but in
humans, the most rich site of
acetylcholine neurons, or neurons that
make acetylcholine, is the parabigeminal
nucleus
or the parabrachial region. All you need
to know is that you have an area in your
brainstem, and that area sends wires,
these axons, up into the area of the
brain that filters sensory input. So, we
have this area of the brain called the
thalamus, and it is getting bombarded
with all sorts of sensory input all the
time. But when I pay attention to
something, I create a cone of attention,
what we call signal to noise goes up.
So, those of you with an engineering
background will be familiar with signal
to noise. Those of you that do not have
an engineering background, don't worry
about it. All it means is that one
particular shout in the crowd comes
through. Acetylcholine acts as a
spotlight.
But epinephrine for alertness,
acetylcholine spotlighting these inputs,
those two things alone are not enough to
get plasticity. There needs to be this
third component, and the third component
is acetylcholine released from an area
of the forebrain called nucleus basalis.
If you really want to get technical,
it's called nucleus basalis of Meynert.
For any of you that are budding
physicians or going to medical school,
you should know that. If you have
acetylcholine released from the
brainstem, acetylcholine released from
nucleus basalis, and epinephrine, you
can change your brain. And this has been
shown again and again and again in a
variety of papers, and it is now
considered a fundamental principle of
how the nervous system works. If you can
access these three things of
epinephrine, acetylcholine from these
two sources,
not only will the nervous system change,
it has to change. It absolutely will
change.
And that is the most important thing for
people to understand if they want to
change their brain. So, now let's talk
about how we would translate all the
scientific information into some
protocols that you can actually apply,
because I think that's what many of
you're interested in. What you do with
your health and your medical care is up
to you. You're responsible for your
health and well-being. So, I'm not going
to tell you what to do or what to take.
I'm going to describe what the
literature tells us and suggests about
ways to access plasticity.
We know we need epinephrine. That means
alertness. Most people accomplish this
through a cup of coffee and a good
night's sleep. So, I will say
you should master your sleep schedule,
and you should figure out how much sleep
you need in order to achieve alertness
when you sit down to learn. But,
once that's in place, the question then
is how do I access this alertness? Well,
there are a number of ways. Some people
use some pretty elaborate psychological
gymnastics. They will tell people that
they're going to do something and create
some accountability. That could be
really good. Or they'll post a picture
of themselves online, and they'll commit
to learning a certain amount losing,
excuse me, a certain amount of weight or
something like this. So, they can use
either
shame-based
practices to potentially embarrass
themselves if they don't follow through.
They'll write checks to organizations
that they hate and insist that they'll
cash them if they don't actually follow
through.
Or they'll do it out of love, you know,
they'll decide that they're going to
run a marathon or learn a language or
something because of somebody they love
or they want to devote it to somebody.
The truth is that from the standpoint of
epinephrine and getting alert and
activated, it doesn't really matter.
Epinephrine is a chemical and your brain
does not distinguish between doing
things out of love or hate, anger or
fear. It really doesn't. All of those
promote autonomic arousal and the
release of epinephrine. So, I think
for most people, if you're feeling not
motivated to make these changes, the key
thing is to identify not just one, but
probably a kit of reasons. Several
reasons as to why you would want to make
this particular change. And being drawn
toward a particular goal that you're
excited about can be one. Also, being
motivated to not be completely afraid,
ashamed, or humiliated for not falling
through on a goal is another. Come up
with two or three things. Fear-based,
perhaps, love-based, perhaps, or perhaps
several of those in order to ensure
alertness,
energy, and attention for the task. And
that brings us to the attention part.
Now, it's one thing to have an electrode
embedded into your brain and increase
the amount of acetylcholine.
It's another to exist in the real world
outside the laboratory and have trouble
focusing, having trouble bringing your
attention to a particular location in
space for a particular event. And
there's a lot of discussion nowadays
about smartphones and devices creating a
sort of attention deficit uh almost at a
clinical level for many people,
including adults.
I think that's largely true. And what it
means, however, is that we all are
responsible for learning how to create
depth of of focus.
There are some important neuroscience
principles to get depth of focus.
I want to briefly talk about the
pharmacology first because I always get
asked about this. People say, "What can
I take to increase my levels of
acetylcholine?" Well, there are things
you can take. Nicotine
is called nicotine because acetylcholine
binds to the nicotinic receptor. There
are two kinds of acetylcholine
receptors, muscarinic and nicotinic, but
the nicotinic ones are involved in
attention and alertness.
I have colleagues. These are not my um
you know, kind of like bro science
buddies. I have those friends, too.
These This is a no Nobel Prize-winning
colleague who choose Nicorette while he
works. But when I asked him, "Why are
you doing this?" he said, "Well, it
increases my alertness and focus." Now,
I've tried chewing Nicorette. It makes
me super jittery. I don't like it
because I can't focus very well. It kind
of takes me too far up the level of
autonomic arousal. I've got friends that
dip Nicorette all day. If you're going
to go down that route, you want to be
very careful how much you rely on those
all the time because the essence of
plasticity is to create a window of
attention and focus that's distinct from
the rest of your day. So, what are some
ways that you can
increase acetylcholine? How do you
increase focus? The best way
to get better at focusing
is to use the mechanisms of focus that
you were born with. And the key
principle here is that mental focus
follows visual focus.
We are all familiar with the fact that
our visual system can be unfocused,
blurry,
or jumping around, or we can be very
laser-focused on one location in space.
What's interesting and vitally important
to understanding how to access neural
plasticity is that you can use your
visual focus, and you can increase your
visual focus as a way of increasing your
mental
focus abilities more broadly. So, I'm
going to explain how to do that.
Plasticity starts with alertness. That
alertness can come from a sense of love,
a a sense of joy, a sense of fear,
doesn't matter.
There are pharmacologic ways to access
alertness, too.
The most common one is, of course,
caffeine. Many people are now also using
Adderall. Adderall will not increase
focus. It increases alertness. It does
not touch the acetylcholine system. The
acetylcholine system and the focus that
it brings is available, as I mentioned,
through pharmacology, but also through
these behavioral practices. And the
behavioral practices that are anchored
in visual focus are going to be the ones
that are going to allow you to develop
great depth and duration of focus. So,
let's think about visual focus for a
second.
When we focus on something visually, we
have two options. We can either look at
a very small region of space with a lot
of detail and a lot of precision, or we
can dilate our gaze and we can see big
pieces of visual space with very little
detail. It's a trade-off. We can't look
at everything at high resolution. This
is why we have these the the pupil more
or less relates to the fovea of the eye,
which is the area in which we have the
most receptors, the highest density of
receptors that perceive light. And so,
our acuity is much better in the center
of our visual field than in our
periphery. When we focus our eyes, we do
a couple things. First of all, we tend
to do that in the center of our visual
field, and our two eyes tend to align in
what's called a vergence eye movement
towards a common point. The other thing
that happens is the lens of our eye
moves so that our brain now no longer
sees the entire visual world, but is
seeing a small cone of visual imagery.
That small cone of visual imagery, or
soda straw view of the world, has much
higher acuity, higher resolution, than
if I were to look at everything.
Now, you say, "Of course, this makes
perfect sense, but that's about visual
attention, not mental attention." Well,
it turns out that focus in the brain is
anchored to our visual system. I'll talk
about blind people in a moment, but
assuming that somebody is sighted, the
key is to learn how to focus better
visually if you want to bring about
higher levels of cognitive or mental
focus. When we move our eyes slightly
inward, maybe you can tell I'm doing
this like
like so, basically shortening or or
making the interpupillary distance, as
it's called, smaller.
Two things happen. Not only do we
develop a smaller visual window into the
world,
but we activate a set of neurons in our
brain stem that trigger the release of
both norepinephrine, epinephrine,
and acetylcholine. Norepinephrine is
kind of similar to epinephrine. So, in
other words, when our eyes are relaxed
in our head, when we're just kind of
looking at our entire visual
environment, moving our head around,
moving through space, we're in optic
flow, things moving past us, or we're
sitting still,
we're looking broadly at our space,
we're relaxed.
When our eyes move slightly inward
toward a particular visual target, our
visual world shrinks, our level of
visual focus goes up, and we know that
this relates to the release of
acetylcholine and epinephrine at the
relevant sites in the brain for
plasticity.
Now, what this means is that if you have
a hard time focusing your mind for sake
of reading or for listening,
you need to practice, and you can
practice, focusing your visual system.
Now, this works best if you practice
focusing your visual system at the
precise distance from the work that you
intend to do for sake of plasticity. So,
how would this look in the real world?
Let's say I am trying to concentrate on
something related to, I don't know,
science. I'm reading a science paper and
I'm having a hard time, it's not
absorbing.
Spending just 60 to 120 seconds focusing
my visual attention on a small window of
my screen, meaning just on my screen
with nothing on it, but bringing my eyes
to that particular location,
increases not just my visual acuity for
that location, but it brings about an
increase in activity
in a bunch of other brain areas that are
associated with gathering information
from this location. So, put simply, if
you want to improve your ability to
focus, practice visual focus. Now, you
may ask, "Well, what about the the
experiment where people were, you know,
feeling this rotating drum or listening
to the auditory cue?" That doesn't
involve vision at all. Ah, if you look
at people who are learning things
audi- with their auditory system, they
will often close their eyes, and that's
not a coincidence. If somebody is
listening very hard,
please don't ask them to look you
directly in the eye while also asking
that they listen to you. That's actually
one of the worst ways to get somebody to
listen to you. If you say, "Now, listen
to me and look me in the eye," the
visual system will take over, and
they'll see your mouth move, but they're
going to hear their thoughts more than
they're going to hear what what you're
saying.
Closing the eyes is one of the best ways
to create a cone of auditory attention,
and this is what low vision or no vision
folks do. They have tremendous capacity
to focus their attention in particular
locations. And for most people, vision
is the primary way to train up this
focus ability and these cones of
attention. So, you absolutely have to
focus on the thing that you're trying to
learn, and you will feel some agitation
because of the epinephrine in your
system. If you're feeling agitation,
and it's challenging to focus, and
you're feeling like you're not doing it
right, chances are you're doing it
right. So, once you get this
epinephrine, this alertness, you get the
acetylcholine released, and you can
focus your attention, then the question
is for how long? And in an earlier
podcast, I talked about these ultradian
cycles that last about 90 minutes. The
typical learning bout should be about 90
minutes. I think
that learning bout will no doubt include
5 to 10 minutes of warm-up period. I
think everyone should give themselves
permission to not be fully focused in
the early part of that bout, but that in
the middle of that bout for the middle
hour or so, you should be able to
maintain focus for about an hour or so.
So, that for me means eliminating
distractions. That means turning off the
Wi-Fi. I put my phone in the other room.
I encourage you to try experiencing what
it is to be completely immersed in an
activity where you feel the agitation
that your attention is drifting, but you
continually bring it back. And that's an
important point, which is that attention
drifts, but we have to re-anchor it. We
have to keep grabbing it back. And the
way to do that, if you're sighted, is
with your eyes. That as your attention
drifts and you look away, you want to
try and
literally maintain visual focus on the
thing that you're trying to learn.
That's the trigger for plasticity. But,
the real secret is that neural
plasticity doesn't occur during
wakefulness. It occurs during sleep.
We now know that
if you focus very hard on something
for about 90 minutes or so, maybe you
even do several bouts of that per day.
If you can do that. Some people can,
some people can only do one focus bout
of learning.
That night and the following nights,
while you sleep, the neural circuits
that were highlighted, if you will, with
acetylcholine transmission, will
strengthen and other ones will be lost.
Which is wonderful, because that's the
essence of plasticity. And what it means
is that when you eventually wake up a
couple days or a week later, you will
will have acquired the knowledge
forever, unless you go through some
process to actively unlearn it.
So, mastering sleep is key in order to
reinforce the learning that occurs. But,
let's say you get a really poor night of
sleep after a bout of learning. Chances
are, if you sleep the next night or the
following night, that learning will
occur. There's a stamp in the brain
where this acetylcholine was released.
It actually marks those synapses
neurochemically
and metabolically, so that those are
synapses are more biased to change. Now,
if you don't ever get that deep sleep,
then you probably won't get those
changes.
There's also a way in which you can
bypass the need for deep sleep, at least
partially, by engaging in what I call
non-sleep deep rest, these NSDR
protocols. But, I just want to discuss
the science of this. There was a paper
that was published
in Cell Reports last year
that shows that if people did It was a
spatial memory task, actually quite
difficult one where they had to remember
the sequence of lights lighting up. And
if there are just two or three lights in
a particular sequence, it's easy. But,
as you get up to 15 or 16 lights and and
thing numbers in the sequence, it
actually gets quite challenging.
If immediately after
and it was immediately after the
learning, the actual performance of this
task, people took a 20-minute non-sleep
deep rest
protocol
or took a a shallow nap, so lying down,
feet slightly elevated perhaps, just
closing their eyes, no sensory input,
the rates of learning were significantly
higher for that information than were
that to just had a good night's sleep
the following night. So, you can
actually accelerate learning with these
NSDR protocols or with brief naps, 90
minutes or less.
For many people, letting the mind drift
where it's not organized in thought
after a period of very deliberate
focused effort is the best way to
accelerate learning and depth of
learning. I want to synthesize some of
the information that we've covered up
until now. Today, I want to make sure
that these key elements that form the
backbone of neuroplasticity are really
embedded in people's minds.
First of all, plasticity occurs
throughout the lifespan. If you want to
learn as an adult,
you have to be alert.
It might seem so obvious, but I think a
lot of people don't think about when in
their 24-hour cycle they're most alert.
Just ask yourself, when during the day
do you typically tend to be most alert?
That will afford you an advantage
in learning specific things during that
period of time. So, don't give up that
period of time for things that are
meaningless, useless, or not aligned
with your goals. That epinephrine
released from your brainstem
is going to occur more readily at
particular phases of of your 24-hour
cycle than others
during the waking phase
of course. You should know when those
are. Increasing acetylcholine can be
accomplished pharmacologically through
nicotine. However,
there are certain dangers for many
people to do that
as well as a cost
financial cost.
Learning how to engage the cholinergic
system through the use of the visual
system, practicing how long can you
maintain focus with blanks as you need
them.
But how long can you maintain visual
focus on a target
just on a piece of paper set a few feet
away in the room or at the level of your
computer screen. These are actually
things that people do in communities
where high levels of visual focus are
necessary. What we're really talking
about here is trying to harness the
mechanisms of attention and get better
at paying attention. You may want to do
that with your auditory system, not with
your visual system.
Either because you're low vision or no
vision or because you're trying to learn
something that relates more to sounds.
You should also ask yourself whether or
not you're trying to focus too much for
too long during the day.
I know some very high-performing
individuals
very high-performing in a variety of
contexts and none of them are focused
all day long. Many of them take walks
down the hallway, sometimes mumbling to
themselves or not paying attention to
anything else. They go for bike rides,
they take walks. They are not trying to
engage their mind at maximum focus all
the time.
Very few people do that
because we learn best in these 90-minute
bouts inside of one of these ultradian
cycles. And I should repeat again that
within that 90-minute cycle, you should
not expect yourself to focus for the
entire period of one 90-minute cycle.
The beginning and end are going to be a
little bit flickering in and out of
focus. How do you know when one of these
90-minute cycles is
starting? Well, typically when you wake
up is the beginning of the first
90-minute cycle, but it does it's not
down to the minute. You'll be able to
tap into your sense of these 90-minute
cycles as you start to engage in these
learning practices should you choose.
And then of course, getting some
non-sleep deep rest or just deliberate
disengagement such as walking or running
or just sitting
eyes closed or eyes open kind of
mindlessly it might seem in a chair just
letting your thoughts move around after
a learning about will accelerate the
rate of plasticity. And then of course,
deep sleep. Many of you have very
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