back to indexHow to Focus to Change Your Brain | Huberman Lab Podcast #6
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Welcome to the Huberman Lab Podcast,
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where we discuss science and science-based tools
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for everyday life.
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My name is Andrew Huberman,
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and I'm a professor of neurobiology and ophthalmology
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at Stanford School of Medicine.
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This podcast is separate
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from my teaching and research roles at Stanford.
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It is, however, part of my desire and effort
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to bring zero cost to consumer information about science
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and science-related tools to the general public.
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In keeping with that theme,
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I want to thank the first sponsor of today's podcast.
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Our first sponsor is Inside Tracker.
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Inside Tracker is a personalized nutrition platform
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that analyzes blood factors and DNA-related factors
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that helps you develop a personalized health plan.
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Many important factors related to our health and wellbeing
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can only be measured by a blood sample and by a DNA sample.
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I've been getting my blood work done for many years now,
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and I use Inside Tracker
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because Inside Tracker makes it very easy
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to not only get the blood work done,
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someone can come to your house,
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or you can go to a clinic, for instance,
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but also to interpret the data that you get.
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Oftentimes, when we get blood work done,
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there are all these numbers and all these levels
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of different hormones and metabolic factors and so forth,
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but one doesn't know what to do with that information.
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Inside Tracker has a terrific dashboard platform
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where you go online and it makes analyzing all that easy,
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and it also provides some very simple
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and straightforward directives
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in terms of exercise, nutrition,
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and other lifestyle factors
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that can help guide your health and improve your health.
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If you'd like to try Inside Tracker,
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you can go to insidetracker.com slash Huberman
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and use the code Huberman at checkout
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to get 25% off your order.
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Today's episode is also brought to us by Headspace.
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Headspace is a meditation app that makes meditating easy.
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I've been meditating on and off for about three decades now,
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and typically it's been more off than on.
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I think like a lot of people,
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I find it hard to stick with a meditation practice.
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A few years ago, I started using the Headspace app,
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and when I did that,
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I found that I was meditating really consistently.
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First of all, the meditations in Headspace
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are backed by quality scientific peer-reviewed studies.
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Second of all, the meditations allow the meditation
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to be kind of easy and fun to access.
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I started first using them when I would travel
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because on JetBlue flights,
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which was the airline I was using,
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the meditations are offered as an alternative
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to watching a TV or a movie.
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And I found that I would arrive feeling much more refreshed
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than had I just sort of zoned out on the TV the whole time
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or even if I had slept.
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I now continue to use Headspace regularly
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pretty much every day for a short meditation,
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and I personally derive tremendous benefits from it.
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If you'd like to try Headspace,
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you can go to headspace.com slash specialoffer,
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and they'll give you one month of all the meditations
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that they have available completely free.
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That's the best offer available right now from Headspace.
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So you can go to headspace.com slash specialoffer,
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and you'll get one month completely free
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all the meditations they have.
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The third sponsor of today's podcast is Made For.
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Made For is a behavioral science company
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that is a subscription model
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in which you engage in specific activities
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each month for 10 months
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in order to bring about positive behavioral change
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and growth mindset.
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The company was founded by former Navy Seal, Patrick Dossett
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as well as Tom's founder, Blake Mycoskie.
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I'm the lead advisor
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of the Scientific Advisory Board at Made For,
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and some of the other members of the advisory board
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include the head of the Chronobiology Unit
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at the National Institutes of Health,
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as well as psychiatrists from Harvard, UC Irvine,
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and many other individuals who are serious about science
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and helped develop the Made For program.
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If you want to try Made For, you can go to getmadefor.com,
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and if you enter Huberman at checkout,
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you'll get 15% off the program.
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Today, we're talking about neural plasticity,
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which is this incredible feature of our nervous systems
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that allows it to change in response to experience.
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Neural plasticity is arguably
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one of the most important aspects of our biology.
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It holds the promise for each and all of us
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to think differently, to learn new things,
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to forget painful experiences,
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and to essentially adapt to anything that life brings us
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by becoming better.
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Neural plasticity has a long and important history,
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and we're not going to review all of it in detail,
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but today, what we are going to do
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is discuss what is neural plasticity,
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as well as the different forms of neural plasticity.
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We're going to talk about how to access neural plasticity
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depending on how old you are
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and depending on the specific types of changes
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that you're trying to create.
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This is a topic for which there are lots of tools,
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as well as lots of biological principles
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that we can discuss.
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So let's get started.
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Most people are familiar with the word neural plasticity.
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It's sometimes also called neuroplasticity.
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Those are the same thing.
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So if I say neuroplasticity or neuroplasticity,
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I'm referring to the same process,
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which is the brain and nervous system's ability
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There are a lot of reasons why the nervous system
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It could do it in response to some traumatic event.
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It could, for instance, create a sense of fear
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around a particular place
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or a fear of automobiles or planes.
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It could also occur when something positive happens,
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like the birth of our first child,
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or when our puppy does something amusing,
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or we see an incredible feat of performance in athleticism.
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The word neuroplasticity means so many things
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to so many different people
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that I thought it would be important
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to just first put a little bit of organizational logic
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around what it is and how it happens.
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Because nowadays, if you were to go online
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and Google the word neuroplasticity,
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you would find hundreds of thousands of references,
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scientific references,
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as well as a lot of falsehoods
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about what neuroplasticity is and how to access it.
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As I mentioned before,
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we're going to talk about the science of it,
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and we're going to talk about the tools
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that allow you to engage this incredible feature
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of your nervous system.
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And that's the first point,
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which is that all of us were born with a nervous system
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that isn't just capable of change,
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but was designed to change.
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When we enter the world,
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our nervous system is primed for learning.
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The brain and nervous system of a baby
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is wired very crudely.
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The connections are not precise,
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and we can see evidence of that
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in the fact that babies are kind of flopping there
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like a kind of a little potato bug with limbs.
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They can't really do much in terms of coordinated movement.
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They certainly can't speak,
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and they can't really do anything with precision.
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And that's because we come into this world over-connected.
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We have essentially wires.
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Those wires have names like axons and dendrites.
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Those are the different parts of the neurons
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discussed in episode one.
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But those little parts and those wires and connections
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Imagine a bunch of roads
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that are all connected to one another in kind of a mess,
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but there are no highways.
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They're all just small roads.
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That's essentially what the young nervous system is like.
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And then as we mature,
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as we go from day one of life
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to 10 years old, 20 years old, 30 years old,
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what happens is particular connections get reinforced
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and stronger and other connections are lost.
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So that's the first important principle that I want everyone
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to understand, which is that developmental plasticity,
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the neuroplasticity that occurs from the time we're born
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until about age 25 is mainly a process
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of removing connections that don't serve our goals well.
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Now, of course, certain events happen
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during that birth to 25 period
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in which positive events and negative events
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are really stamped down into our nervous system
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in a very dramatic fashion
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by what we call one trial learning.
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We experienced something once
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and then our nervous system is forever changed
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by that experience.
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Unless of course we go through some work
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to undo that experience.
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So I want you to imagine in your mind
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that when you were brought into this world,
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you were essentially a widely connected web of connections
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that was really poor at doing any one thing.
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And that through your experience,
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what you were exposed to by your parents or other caretakers
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through your social interactions, through your thoughts,
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through the languages that you learn,
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through the places you traveled or didn't travel,
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your nervous system became customized
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to your unique experience.
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Now, that's true for certain parts of your brain
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that are involved in what we call representations
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of the outside world.
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A lot of your brain is designed to represent the visual world
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or represent the auditory world
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or represent the gallery of smells
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that are possible in the world.
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However, there are aspects of your nervous system
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that were designed not to be plastic.
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They were wired so that plasticity
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or changes in those circuits is very unlikely.
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Those circuits include things like
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the ones that control your heartbeat,
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the ones that control your breathing,
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the ones that control your digestion.
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And thank goodness that those circuits were set up that way
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because you want those circuits to be extremely reliable.
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You never want to have to think about
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whether or not your heart will beat
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or whether or not you will continue breathing
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or whether or not you'll be able to digest your food.
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So many nervous system features like digestion
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and breathing and heart rate are hard to change.
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Other aspects of our nervous system
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are actually quite easy to change.
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And one of the great gifts of childhood,
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adolescence and young adulthood,
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is that we can learn through almost passive experience.
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We don't have to focus that hard
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in order to learn new things.
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In fact, children go from being able
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to speak no language whatsoever,
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to being able to speak many, many words
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and comprise sentences,
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including words they've never heard before,
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which is remarkable.
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It means that the portions of the brain
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involved in speech and language
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are actually primed to learn and create new combinations.
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What this tells us is that the young brain
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is a plasticity machine.
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But then right about age 25,
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plus or minus a year or two, everything changes.
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After age 25 or so,
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in order to get changes in our nervous system,
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we have to engage in a completely different set of processes
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in order to get those changes to occur
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and for them, more importantly, to stick around.
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And this is something that I think is vastly overlooked
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in the popular culture discussion about neuroplasticity.
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People always talk about fire together, wire together.
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Fire together, wire together is true.
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It is the statement of my colleague at Stanford,
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Carla Schatz, and it's an absolute truth
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about the way that the nervous system wires up
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early in development.
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But fire together, wire together
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doesn't apply in the same way after age 25.
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And so we have these little memes
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and these little quotes that circulate on the internet
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like fire together, wire together,
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or there's a famous quote
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from the greatest neurobiologist of all time, Ramon y Cajal.
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I think it goes something like, you know,
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should somebody wish to change their nervous system,
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they could be the sculptor of their nervous system
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in any way they want, something like that.
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And that sounds great.
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I mean, who wouldn't want to change their nervous system
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any way they want?
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But what's lost in those statements
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is how to actually accomplish that.
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And we're going to cover that today.
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But please understand that early in development,
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your nervous system is connected very broadly
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in ways that make it very hard to do anything well.
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From birth until about age 25,
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those connections get refined mainly through the removal
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of connections that don't serve us
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and the incredible strengthening of connections
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that relate to either powerful experiences
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or that allow us to do things like walk and talk
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and do math, et cetera.
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And then after age 25, if we want to change
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those connections, those super highways of connectivity,
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we have to engage in some very specific processes
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and those processes as we'll soon learn are gated,
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meaning you can't just decide to change your brain.
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You actually have to go through a series of steps
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to change your internal state in ways
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that will allow you to change your brain.
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I just want to acknowledge that Costello is snoring
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particularly loud today.
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Some of you seem very keen at picking up on his snoring.
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Others of you can't hear his snoring.
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It's very low rumbling sound.
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And whether or not you can or you can't
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probably relates to the sensitivity of your hearing.
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We're actually going to talk about perfect pitch today
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and range of auditory detection.
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And so if you can hear Costello's snoring,
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enjoy, if you can't, enjoy.
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I want to talk about how the nervous system changes.
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What are these changes?
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Many of us have been captivated by the stories
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in the popular press about the addition of new neurons.
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This idea, oh, if you go running or you exercise,
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your brain actually makes new neurons.
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Well, I'm going to give you the bad news first,
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which is that after puberty, so after about age 14 or 15,
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the human brain and nervous system adds very few,
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if any, new neurons.
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The idea that new neurons could be added to the brain
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is one that has a rich history in experimental science.
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It's clear that in rodents and in some non-human primates,
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new neurons, a process called neurogenesis,
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can occur in areas of the brain,
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such as the olfactory bulb,
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which is of course involved in smell,
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as well as a region of our hippocampus,
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the center of the brain involved in memory
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called the dentate gyrus of the hippocampus.
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And there is strong evidence that new neurons
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can be added to those structures throughout the lifespan.
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In humans, the evidence is a little bit more controversial.
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It's clear that we can add new neurons
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to our olfactory bulb.
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In fact, if any of you have ever had the unfortunate
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experience of being hit on the head too hard,
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the wires called axons from those olfactory neurons
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that live in your nose can get sheared off
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because they have to pass through a bony plate
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called the cribriform plate.
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And the cribriform plate can shear those axons
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and people can become what's called anosmic.
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They won't be able to smell.
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But over time, those neurons,
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unlike most all central nervous system neurons,
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can grow those connections back
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and even reestablish new neurons
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added to the olfactory bulb.
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They come from elsewhere deep in the brain
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and they migrate through a pathway
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called the rostral migratory stream.
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You can Google these words
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and look up some of the descriptions of this
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if you'd like to learn more.
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So indeed, there's some evidence
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that the neurons responsible for smell
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can be replaced throughout the lifespan,
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certainly in very young individuals
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from birth till about age 15 or so.
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Whether or not there are new neurons
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added to the hippocampus,
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the memory center of the human brain, isn't clear.
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Many years ago, Rusty Gage's lab at the Salk Institute
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did a really important study
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looking at terminally ill cancer patients
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and injecting them with a label, a dye,
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that is incorporated only into new neurons.
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And after these patients died,
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their brains were harvested,
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the brains were looked at,
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and there were new neurons there.
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There was evidence for new neurons.
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Those results, I think, stand over time.
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But what was not really discussed
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in the popular press discussion around those papers
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was that it was very few cells that were being added.
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And a number of papers have come along over the years,
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mainly from labs at UCSF,
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although from others as well,
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showing that if there are new neurons
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added to the adult brain,
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it's an infinitesimally small number of new neurons.
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So that's the depressing part.
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We don't get new neurons.
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After we're born, we pretty much have the neurons
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that we're going to use our entire life.
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And yes, as we get older
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and we start to lose certain functions in our brain,
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But all is not lost, so to speak,
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because there are other ways in which neural circuits
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can create new connections and add new functions,
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including new memory, new abilities,
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and new cognitive functions.
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And those are mainly through the process
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of making certain connections,
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which of course are those things we call synapses
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between neurons, making those connections stronger
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so they're more reliable, they're more likely to engage,
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as well as removing connections.
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And the removal of connections is vital
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to say, moving through a grieving process
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or removing the emotional load of a traumatic experience.
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So even though we can't add new neurons
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throughout our lifespan,
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at least not in very great numbers,
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it's clear that we can change our nervous system,
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that the nervous system is available for change,
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that if we create the right set of circumstances
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in our brain, chemical circumstances,
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and if we create the right environmental circumstances
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around us, our nervous system will shift into a mode
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in which change isn't just possible, but it's probable.
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As I mentioned before,
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the hallmark of the child nervous system is change.
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It wants to change.
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The whole thing, everything from the chemicals
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that are sloshing around in there
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to the fact that there's a lot of space between the neurons,
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a lot of people don't know this,
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but early in development,
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there's a lot of space between the neurons,
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and so the neurons can literally move around
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and sample different connections very easily,
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removing some and keeping others.
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As we get older, the so-called extracellular space
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is actually filled up by things called extracellular matrix
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and glial cells, glia means glue.
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Those cells are involved in a bunch of different processes,
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but they start to fill in all the space,
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kind of like pouring concrete between rocks,
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and when that happens,
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it becomes much harder to change the connections
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One of the ways in which we can all get plasticity
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at any stage throughout the lifespan
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is through deficits and impairments
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in what we call our sensory apparatus,
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our eyes, our ears, our nose, our mouth,
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and there are some very dramatic
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and somewhat tragic examples of people, for instance,
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who have genetic mutations where they are born
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without a nose and without any olfactory structures
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in the brain, so they cannot smell.
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In that case, areas of the brain
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that normally would represent smell
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become overtaken by areas of the brain
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involved in other things like touch and hearing and sight.
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In individuals that are blind from birth,
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the so-called occipital cortex,
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the visual cortex in the back,
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becomes overtaken by hearing.
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The neurons there will start to respond to sounds
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as well as braille touch,
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and actually there's one particularly tragic incident
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where a woman who was blind since birth,
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and because of neuroimaging studies,
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we knew her visual cortex was no longer visual.
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It was responsible for braille reading and for hearing.
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She had a stroke that actually took out
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most of the function of her visual cortex,
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so then she was blind, she couldn't braille read or hear.
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She did recover some aspect of function.
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Now, most people, they don't end up
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in that highly unfortunate situation,
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and what we know is that, for instance,
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blind people who use their visual cortex
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for braille reading and for hearing
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have much better auditory acuity and touch acuity,
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meaning they can sense things with their fingers
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and they can sense things with their hearing
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that typical sighted folks wouldn't be able to.
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In fact, you will find a much greater incidence
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of perfect pitch in people that are blind,
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and that tells us that the brain,
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and in particular this area we call the neocortex,
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which is the outer part,
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is really designed to be a map
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of our own individual experience.
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So these, what I call experiments of impairment or loss
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where somebody is blind from birth or deaf from birth,
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or maybe has a limb development impairment
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where they have a stump instead of an entire limb
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with a functioning hand,
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their brain will represent the body plan that they have,
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not some other body plan.
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But the beauty of the situation is that the real estate
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up in the skull, that neocortex,
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the essence of it is to be a customized map of experience.
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Now, it is true, however,
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that if let's say I were to be blind when I'm 50,
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I'm 45 right now, I've always been sighted.
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If I was blind at 50,
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I'll probably have less opportunity
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to use my formerly visual cortex
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for things like braille reading and hearing,
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because my brain has changed.
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It's just not the same brain I had when I was a baby.
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So there's actually a principle of biology.
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Not many people know this.
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It's actually a principle of neurology,
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which is called the Kennard principle,
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which says if you're going to have a brain injury,
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you wanna have it early in life.
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And of course, better to not have a brain injury at all,
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but if you're going to have it,
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you wanna have it early in life.
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And this is based on a tremendous number of experiments
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examining the amount of recovery
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and the rate of recovery in humans
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that had lesions to their brain
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either early in life or later in life.
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So the Kennard principle says
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better to have injuries early in life.
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Now, that's reassuring for the young folks.
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It's not so reassuring for the older folks.
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But there are aspects of neuroplasticity
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that have nothing to do with impairments.
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I mean, earlier I said,
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we're all walking around with this map,
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this representation of the world around us
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so we can see edges, we can see colors,
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except for folks that are colorblind, of course.
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And we also have a map of emotional experience.
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We have a map of whether or not
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certain people are trustworthy,
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certain people aren't trustworthy.
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A few years ago, I was at a course
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and a woman came up to me and she said,
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I wasn't teaching the course, I was in the course.
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And she said, I just have to tell you
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that every time you speak, it really stresses me out.
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And I said, well, I've heard that before,
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but do you want to be more specific?
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And she said, yeah, your tone of voice reminds me
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of somebody that I had a really terrible experience with.
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I said, well, okay, well, I can't change my voice
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but I really appreciate that you acknowledge that
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and it also will help explain
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why you seem to cringe every time I speak,
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which I hadn't noticed until then.
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But after that, I did notice she had a very immediate
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and kind of visceral response to my speech.
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Perhaps some of you are having that right now.
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But in any event, over the period of this two-week course,
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she would come back every once in a while and say,
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you know what, I think just by telling you
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that your voice was really difficult for me to listen to,
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it's actually becoming more tolerable to me.
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And by the end, we actually became pretty good friends
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and we're still in touch.
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And so what this says is that the recognition of something,
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whether or not that's an emotional thing
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or a desire to learn something else
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is actually the first step in neuroplasticity.
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And that's because our nervous system
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has two broad sets of functions.
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Some of those functions are reflexive.
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Things like our breathing, our heart rate are obvious ones.
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But other aspects are reflexive like our ability to walk.
link |
If I get up out of this chair and walk out of the door,
link |
I don't think about each step that I'm taking
link |
and that's because I learned how to walk during development.
link |
But when we decide that we're going to shift
link |
some sort of behavior or some reaction
link |
or some new piece of information that we want to learn
link |
is something that we want to bring into our consciousness,
link |
that awareness is a remarkable thing
link |
because it cues the brain and the rest of the nervous system
link |
that when we engage in those reflexive actions
link |
going forward, that those reflexive actions
link |
are no longer fated to be reflexive.
link |
Now, if this sounds a little bit abstract,
link |
we're going to talk about protocols for how to do this.
link |
But the first step in neuroplasticity
link |
is recognizing that you want to change something.
link |
And you should immediately say,
link |
well, kids don't go into school and say,
link |
oh, I want to learn language
link |
or I want to learn social interactions.
link |
And that's the beauty of childhood.
link |
The whole brain has this switch flipped
link |
that is making change possible.
link |
But after that, we have to be deliberate.
link |
We have to know what it is exactly that we want to change.
link |
Or if we don't know exactly what it is
link |
that we want to change,
link |
we at least have to know that we want to change something
link |
about some specific experience.
link |
In this case, I believe that she came and told me
link |
that my voice was really awful for her to listen to,
link |
not to make me feel bad or for any other reason,
link |
except that she wanted it to not be the case.
link |
And she knew I wasn't going to stop talking.
link |
So she decided to call it
link |
to her consciousness and mine as well.
link |
So that's important.
link |
If you want to learn something
link |
or you want to change your nervous system in any way,
link |
whether or not it's because of some impairment
link |
or because of something that you want to acquire,
link |
a cognitive skill, a motor skill, an emotional skill,
link |
the first thing is recognizing what that thing is.
link |
And that often can be the hardest thing to identify.
link |
But the brain has these self-recognition mechanisms.
link |
And those self-recognition mechanisms
link |
are not vague, spiritual, or mystical,
link |
or even psychological concepts.
link |
They are neurochemicals.
link |
We're going to talk next about the neurochemicals
link |
that stamp down particular behaviors
link |
and thoughts and emotional patterns
link |
and tell the rest of the nervous system,
link |
this is something to pay attention to
link |
because this is in the direction
link |
of the change that I want to make.
link |
So I'll repeat that.
link |
There are specific chemicals
link |
that when we are consciously aware
link |
of a change we want to make,
link |
or even just that we want to make some change,
link |
chemicals are released in the brain
link |
that allow us the opportunity to make those changes.
link |
Now there are specific protocols that science tells us
link |
we have to follow if we want those changes to occur.
link |
But that self-recognition is not a kind of murky concept.
link |
What it is is it's our forebrain,
link |
in particular our prefrontal cortex,
link |
signaling the rest of our nervous system
link |
that something that we're about to do here,
link |
feel, or experience is worth paying attention to.
link |
So we'll pause there and then I'm going to move forward.
link |
One of the biggest lies in the universe
link |
that seems quite prominent right now
link |
is that every experience you have changes your brain.
link |
People love to say this.
link |
your brain is going to be different after this lecture
link |
or that your brain is going to be different
link |
after today's class than it was two days ago.
link |
And that's absolutely not true.
link |
The nervous system doesn't just change
link |
because you experienced something
link |
unless you're a very young child.
link |
The nervous system changes
link |
when certain neurochemicals are released
link |
and allow whatever neurons are active
link |
in the period in which those chemicals are swimming around
link |
to strengthen or weaken the connections of those neurons.
link |
Now, this is best illustrated
link |
through a little bit of scientific history.
link |
The whole basis of neuroplasticity
link |
is essentially ascribed to two individuals,
link |
although there were a lot more people
link |
that were involved in this work.
link |
Those two individuals go by the name
link |
David Hubel and Torsten Wiesel.
link |
David Hubel and Torsten Wiesel started off at Johns Hopkins,
link |
moved to Harvard Medical School.
link |
And in the 70s and 80s,
link |
they did a series of experiments
link |
recording electrical activity in the brain.
link |
They were in the visual cortex,
link |
meaning they put the electrodes in the visual cortex,
link |
and they were exploring how vision works
link |
and how the visual brain organizes
link |
all the features of the visual world
link |
to give us these incredible things
link |
we call visual perceptions.
link |
But Hubel was a physician,
link |
and he was very interested in what happens
link |
when, for instance, a child comes into the world
link |
and they have a cataract.
link |
The lens of their eye isn't clear, but it's opaque.
link |
Or when a kid has a lazy eye
link |
or the eyes have what's called strabismus,
link |
which is when the eyes either deviate outward or inward.
link |
These are very common things of childhood,
link |
especially in particular areas of the world.
link |
And what David and Torsten did
link |
is they figured out that there was a critical period
link |
in which if clear vision did not occur,
link |
the visual brain would completely rewire itself
link |
basically to represent
link |
whatever bit of visual information was coming in.
link |
So they did these experiments
link |
that kind of simulate a droopy eye or a deviating eye
link |
where they would close one eyelid.
link |
And then what they found is that the visual brain
link |
would respond entirely to the open eye.
link |
It was sort of a takeover of the visual brain
link |
representing the open eye.
link |
Many experiments in many different sensory systems
link |
followed up on this.
link |
There are beautiful experiments, for instance,
link |
from Greg Reckenzone's lab up at UC Davis
link |
and Mike Merzenich's labs at UCSF
link |
showing that, for instance,
link |
if two fingers were taped together early in development,
link |
so they weren't moving independently,
link |
the representation of those two fingers
link |
would become fused in the brain
link |
so that the person couldn't actually distinguish
link |
the movements and the sensations
link |
of the two fingers separately.
link |
Pretty remarkable.
link |
All of this is to say that David and Torsten's work,
link |
for which they won a Nobel Prize,
link |
they shared it with Roger Sperry,
link |
their work showed that the brain is in fact
link |
a customized map of the outside world.
link |
We said that already.
link |
But that what it's doing is it's measuring
link |
the amount of activity for a given part of our body,
link |
one eye or the other,
link |
or our fingers, this finger or that finger,
link |
and all of those inputs are competing
link |
for space in the brain.
link |
Now, this is fundamentally important
link |
because what it means is that
link |
if we are to change our nervous system in adulthood,
link |
we need to think about not just what we're trying to get,
link |
but what we're trying to give up.
link |
We can't actually add new connections
link |
without removing something else.
link |
And that might seem like kind of a stinger,
link |
but it actually turns out to be a great advantage.
link |
One of the key experiments that David and Torsten did
link |
was an experiment where they closed both eyes,
link |
where they essentially removed all visual input
link |
early in development.
link |
Now, this is slightly different than blindness
link |
because it was transient,
link |
it was only for a short period of time.
link |
But what they found is when they did that,
link |
there was no change.
link |
However, if they closed just one eye,
link |
there was a huge change.
link |
So when people tell you,
link |
oh, at the end of today's lecture,
link |
or at the end of something,
link |
your brain is going to be completely different,
link |
that's simply not true.
link |
If you're older than 25,
link |
your brain will not change
link |
unless there's a selective shift in your attention
link |
or a selective shift in your experience
link |
that tells the brain it's time to change.
link |
And those changes occur through the ways I talked about
link |
before strengthening and weakening of particular connections.
link |
They have names like long-term potentiation,
link |
long-term depression,
link |
which has nothing to do with emotional depression,
link |
by the way, spike timing dependent plasticity.
link |
I threw out those names not to confuse you,
link |
but for those of you that would like
link |
more in-depth exploration of those,
link |
please, you can go Google those and look them up.
link |
There are great Wikipedia pages for them
link |
and you can go down the paper trail.
link |
I might even touch on them in some subsequent episodes.
link |
But the important thing to understand
link |
is that if we want something to change,
link |
we really need to bring an immense amount of attention
link |
to whatever it is that we want to change.
link |
This is very much linked to the statement I made earlier
link |
about it all starts with an awareness.
link |
Now, why is that attention important?
link |
Well, David and Torrenston won their Nobel Prize
link |
and they certainly deserved it.
link |
They probably deserve two
link |
because they also figured out how vision works.
link |
And I might be biased
link |
because they're my scientific great-grandparents,
link |
but I think everybody in the field of neuroscience agrees
link |
that Hubel and Wiesel, as they're called,
link |
H and W for those in the game,
link |
absolutely deserved a Nobel Prize for their work
link |
because they really unveiled the mechanisms
link |
of brain change, of plasticity.
link |
David passed away a few years ago.
link |
Torrenston's still alive.
link |
He's in his late 90s.
link |
He's still at the Rockefeller University.
link |
He's sharp as a tack.
link |
He still jogs several miles a day.
link |
He's really into art and a number of other things.
link |
He's also a super nice guy.
link |
Hubel was a really nice guy as well.
link |
It's also, he was a great Frisbee player, I discovered,
link |
because he beat me in a game of ultimate
link |
when he was like 80,
link |
which still has me a little bit irked.
link |
But anyway, Hubel and Wiesel did an amazing thing
link |
for science that will forever change the way
link |
that we think about the brain.
link |
However, they were quite wrong
link |
about this critical period thing.
link |
The critical period was this idea
link |
that if you were to deprive the nervous system of an input,
link |
say closing one eye early in development
link |
and the rest of the visual cortex is taken over
link |
by the representation of the open eye,
link |
that you could never change that
link |
unless you intervened early.
link |
And this actually formed the basis
link |
for why a kid that has a lazy eye or a cataract,
link |
why even though there are some issues
link |
with anesthesia in young children,
link |
why now we know that you want to get in there early
link |
and fix the cataract or fix the strabismus,
link |
that's what ophthalmologists do.
link |
However, their idea that you had to do it early
link |
or else there was no opportunity
link |
to rescue the nervous system deficit later on,
link |
turned out, wasn't entirely true.
link |
In the early 90s, a graduate student
link |
by the name of Greg Reconzone was in the laboratory
link |
of a guy named Mike Merzenich at UCSF.
link |
And they set out to test this idea
link |
that if one wants to change their brain,
link |
they need to do it early in life
link |
because the adult brain simply isn't plastic,
link |
it's not available for these changes.
link |
And they did a series of absolutely beautiful experiments.
link |
By now, I think we can say proving
link |
that the adult brain can change
link |
provided certain conditions are met.
link |
Now, the experiments they did are tough.
link |
They were tough on the experimenter
link |
and they were tough on the subject.
link |
I'll just describe one.
link |
Let's say you were a subject in one of their experiments.
link |
You would come into the lab and you'd sit down at a table
link |
and they would record from or image your brain
link |
and look at the representation of your fingers,
link |
the digits as we call them.
link |
And there would be a spinning drum,
link |
literally like a stone drum in front of you
link |
or metal drum that had little bumps.
link |
Some of the bumps were spaced close together,
link |
some of them were spaced far apart.
link |
And they would do these experiments
link |
where they would expect their subjects
link |
to press a lever whenever, for instance,
link |
the bumps got closer together or further apart.
link |
And these were very subtle differences.
link |
So in order to do this, you really have to pay attention
link |
to the distance between the bumps.
link |
And these were not braille readers or anyone skilled
link |
in doing these kinds of experiments.
link |
What they found was that as people paid
link |
more and more attention to the distance between these bumps
link |
and they would signal when there was a change
link |
by pressing a lever.
link |
As they did that, there was very rapid changes,
link |
plasticity in the representation of the fingers.
link |
And it could go in either direction.
link |
You could get people very good at detecting the distance
link |
between bumps that the distance was getting smaller
link |
or the distance was getting greater.
link |
So people could get very good at these tasks
link |
that they're kind of hard to imagine
link |
how they would translate to the real world
link |
for a non braille reader.
link |
But what it told us is that these maps of touch
link |
were very much available for plasticity.
link |
And these were fully adult subjects.
link |
They're not taking any specific drugs.
link |
They don't have any impairments that we're aware of.
link |
And what it showed, what it proved
link |
is that the adult brain is very plastic.
link |
And they did some beautiful control experiments
link |
that are important for everyone to understand,
link |
which is that sometimes they would bring people in
link |
and they would have them touch these bumps
link |
on this spinning drum.
link |
But they would have the person pay attention
link |
to an auditory cue.
link |
Every time a tone would go off
link |
or there was a shift in the pitch of that tone,
link |
they would have to signal that.
link |
So the subject thought they were doing something
link |
related to touch and hearing.
link |
And all that showed was that it wasn't just the mere action
link |
of touching these bumps.
link |
They had to pay attention to the bumps themselves.
link |
If they were placing their attention
link |
on the auditory cue, on the tone,
link |
well, then there was plasticity
link |
in the auditory portion of the brain,
link |
but not on the touch portion of the brain.
link |
And this really spits in the face of this thing
link |
that you hear so often, which is every experience
link |
that you have is going to change the way your brain works.
link |
The experiences that you pay super careful attention to
link |
are what open up plasticity.
link |
And it opens up plasticity to that specific experience.
link |
So the question then is why?
link |
And Merzenich and his graduate students and postdocs
link |
went on to address this question of why.
link |
And it turns out the answer
link |
is a very straightforward neurochemical answer.
link |
And inside of that answer is the opportunity
link |
for any of us to change our brain at any point
link |
throughout our lifespan,
link |
essentially for anything that we want to learn.
link |
That could be subtracting an emotion
link |
from an experience we've had.
link |
It could be building a greater range of emotion.
link |
It could be learning new information
link |
like learning a new language.
link |
It could be learning new motor skill like dance or sport,
link |
or it could be some combination of cognitive motor.
link |
So for instance, an air traffic controller
link |
has to do a lot with their mind
link |
in addition to a lot with their hands.
link |
So it's not just cognitive,
link |
it's not just motor, but combined.
link |
So we're going to talk about what that chemical is,
link |
but to just give you an important hint,
link |
that chemical is the same chemical of stress.
link |
This is not a discussion about stress per se.
link |
In a future podcast episode,
link |
we'll talk all about stress and tools to deal with stress.
link |
It's something my lab works on quite extensively.
link |
And it's a topic that I enjoy discussing.
link |
But this is a topic about brain change.
link |
And what I just told you is that
link |
in order to change the brain,
link |
you have to pay careful attention.
link |
And the immediate question should be, well, why?
link |
Well, the answer is that when we pay careful attention,
link |
there are two neurochemicals,
link |
neuromodulators as they're called,
link |
that are released from multiple sites in our brain
link |
that highlight the neural circuits
link |
that stand a chance of changing.
link |
Now, it's not necessarily the case
link |
that they're going to change,
link |
but it's the first gate that has to open
link |
in order for change to occur.
link |
And the first neurochemical is epinephrine, also adrenaline.
link |
We call it adrenaline when it's released
link |
from the adrenal glands above our kidneys,
link |
that's in the body.
link |
We call it epinephrine in the brain,
link |
but they are chemically identical substances.
link |
Epinephrine is released from a region in the brainstem
link |
called locus coeruleus.
link |
Fancy name, you don't need to know it unless you want to.
link |
Locus coeruleus sends out these little wires we call axons
link |
such that it hoses the entire brain, essentially,
link |
in this neurochemical epinephrine.
link |
Now, it's not always hosing the brain with epinephrine.
link |
It's only when we are in high states of alertness
link |
that this epinephrine is released.
link |
But the way this circuit is designed,
link |
it's very nonspecific.
link |
It's essentially waking up the entire brain.
link |
That's because the way that epinephrine works
link |
by binding particular receptors
link |
is to increase the likelihood that neurons will be active.
link |
So no alertness, no neuroplasticity.
link |
However, alertness alone is not sufficient.
link |
As we would say, it's necessary,
link |
but not sufficient for neuroplasticity.
link |
We know this is true also from the work of Hubel and Wiesel,
link |
where they looked at brain plasticity
link |
in response to certain experiences
link |
in subjects that were either awake or asleep.
link |
And I hate to break it to you,
link |
but you cannot just simply listen to things in your sleep
link |
and learn those materials.
link |
Later, I'll talk about how you can do certain things
link |
in your sleep that you're unaware of
link |
that can enhance learning of things
link |
that you were aware of while you were awake,
link |
but that is not the same as just listening to some music
link |
or listening to a tape while you sleep
link |
and expecting it to sink in, so to speak.
link |
Epinephrine is released when we pay attention
link |
and when we are alert.
link |
But the most important thing for getting plasticity
link |
is that there'll be epinephrine,
link |
which equates to alertness,
link |
plus the release of this neuromodulator acetylcholine.
link |
Now, acetylcholine is released from two sites in the brain.
link |
One is also in the brainstem,
link |
and it's named different things in different animals,
link |
but in humans, the most rich site of acetylcholine neurons
link |
or neurons that make acetylcholine
link |
is the parabigeminal nucleus or the parabrachial region.
link |
There are a number of different names
link |
of these aggregates of neurons.
link |
You don't need to know the names.
link |
All you need to know is that
link |
you have an area in your brainstem,
link |
and that area sends wires, these axons,
link |
up into the area of the brain that filters sensory input.
link |
So we have this area of the brain called the thalamus,
link |
and it is getting bombarded
link |
with all sorts of sensory input all the time.
link |
Costello's snoring off to my right,
link |
the lights that are in the room,
link |
the presence of my computer to my left.
link |
All of that is coming in,
link |
but when I pay attention to something,
link |
like if I really hone in on Costello's snoring,
link |
I create a cone of attention,
link |
and what that cone of attention reflects
link |
is that acetylcholine is now amplifying the signal
link |
of sounds that Costello is making with his snoring
link |
and essentially making that signal greater
link |
than all the signal around it.
link |
What we call signal-to-noise goes up.
link |
So those of you with an engineering background
link |
will be familiar with signal-to-noise.
link |
Those of you who do not have an engineering background,
link |
don't worry about it.
link |
All it means is that one particular shout in the crowd
link |
comes through, Costello's snoring becomes more salient,
link |
more apparent relative to everything else going on.
link |
Acetylcholine acts as a spotlight,
link |
but epinephrine for alertness,
link |
acetylcholine spotlighting these inputs,
link |
those two things alone are not enough to get plasticity.
link |
There needs to be this third component,
link |
and the third component is acetylcholine released
link |
from an area of the forebrain called nucleus basalis.
link |
If you really want to get technical,
link |
it's called nucleus basalis of minort.
link |
For any of you that are budding physicians
link |
or going to medical school, you should know that.
link |
If you have acetylcholine released from the brainstem,
link |
acetylcholine released from nucleus basalis,
link |
and epinephrine, you can change your brain.
link |
And I can say that with confidence
link |
because Merzenich and Recanzone, as well as other members
link |
of the Merzenich lab, Michael Kilgard and others,
link |
did these incredible experiments
link |
where they stimulated the release of acetylcholine
link |
from nucleus basalis, either with an electrode
link |
or with some other methods that we'll talk about.
link |
And what they found was when you stimulate
link |
these three brain regions, locus coeruleus,
link |
the brainstem source of acetylcholine,
link |
and then the basal forebrain source of acetylcholine,
link |
when you have those three things,
link |
whatever you happen to be listening to,
link |
doing or paying attention to, immediately in one trial
link |
takes over the representation
link |
of a particular area of the brain,
link |
you essentially get rapid, massive learning in one shot.
link |
And this has been shown again and again and again
link |
in a variety of papers,
link |
also by a guy named Norm Weinberger from UC Irvine.
link |
And it is now considered a fundamental principle
link |
of how the nervous system works.
link |
So while Hubel and Wiesel talked about critical periods
link |
in developmental plasticity,
link |
it's very clear from the work of Merzenich and Weinberg
link |
and others that if you get these three things,
link |
if you can access these three things
link |
of epinephrine acetylcholine from these two sources,
link |
not only will the nervous system change, it has to change.
link |
It absolutely will change.
link |
And that is the most important thing for people to understand
link |
if they want to change their brain.
link |
You cannot just passively experience things.
link |
And repetition can be important,
link |
but the way to use repetition to change your brain
link |
is fundamentally different.
link |
So now let's talk about how we would translate
link |
all the scientific information and history
link |
into some protocols that you can actually apply,
link |
because I think that's what many of you are interested in.
link |
And I'm willing to bet that most of you are not interested
link |
in lowering electrodes into your nucleus basalis,
link |
and frankly, neither am I.
link |
In episode one of the Huberman Lab Podcast,
link |
I described the various ways that people can monitor
link |
and change their nervous system.
link |
Those ways include brain-machine interface,
link |
pharmacology, behavioral practices,
link |
and those behavioral practices, of course,
link |
can include some dos, do this, and some don'ts,
link |
don't do that, et cetera.
link |
In thinking about neuroplasticity,
link |
I want to have a very frank conversation
link |
about what one can do,
link |
but also acknowledge this untapped capacity
link |
that I'm just not hearing about out there,
link |
which is one can also combine behavioral practices
link |
with pharmacology.
link |
One can combine behavioral practices
link |
with brain-machine interface.
link |
And you don't have to do that.
link |
In fact, I'm not recommending you do anything in particular.
link |
As always, I'll say it again,
link |
I'm not a physician, so I don't prescribe anything.
link |
I'm a professor, so I profess a lot of things.
link |
What you do with your health and your medical care
link |
You're responsible for your health and wellbeing.
link |
So I'm not going to tell you what to do or what to take.
link |
I'm going to describe what the literature tells us
link |
and suggests about ways to access plasticity.
link |
We know we need epinephrine.
link |
That means alertness.
link |
Most people accomplish this through a cup of coffee
link |
and a good night's sleep.
link |
So I will say you should master your sleep schedule,
link |
and you should figure out how much sleep you need
link |
in order to achieve alertness when you sit down to learn.
link |
All the tools and more science
link |
than probably you ever wanted to hear about sleep
link |
and how to get better at sleeping and timing your sleep,
link |
et cetera, and naps, and all of that
link |
is in episodes two, three, four, and five
link |
of the Huberman Lab Podcast.
link |
So I encourage you to refer to those
link |
if your sleep is not where you would like it to be.
link |
Your ability to engage in deliberate focused alertness
link |
is in direct proportion
link |
to how well you are sleeping on a regular basis.
link |
I think that's kind of an obvious one.
link |
So get your sleep handled.
link |
But once that's in place, the question then is
link |
how do I access this alertness?
link |
Well, there are a number of ways.
link |
Some people use some pretty elaborate
link |
psychological gymnastics.
link |
They will tell people that they're going to do something
link |
and create some accountability.
link |
That could be really good.
link |
Or they'll post a picture of themselves online,
link |
and they'll commit to learning a certain amount,
link |
losing, excuse me, a certain amount of weight
link |
or something like this.
link |
So they can use either shame-based practices
link |
to potentially embarrass themselves
link |
if they don't follow through.
link |
They'll write checks to organizations that they hate
link |
and insist that they'll cash them
link |
if they don't actually follow through.
link |
Or they'll do it out of love.
link |
They'll decide that they're going to run a marathon
link |
or learn a language or something
link |
because of somebody they love
link |
or they want to devote it to somebody.
link |
The truth is that from the standpoint of epinephrine
link |
and getting alert and activated, it doesn't really matter.
link |
Epinephrine is a chemical,
link |
and your brain does not distinguish
link |
between doing things out of love or hate, anger or fear.
link |
It really doesn't.
link |
All of those promote autonomic arousal
link |
and the release of epinephrine.
link |
So I think for most people,
link |
if you're feeling not motivated to make these changes,
link |
the key thing is to identify not just one,
link |
but probably a kit of reasons,
link |
several reasons as to why you would want
link |
to make this particular change.
link |
And being drawn toward a particular goal
link |
that you're excited about can be one.
link |
Also being motivated to not be completely afraid,
link |
ashamed or humiliated for not following through
link |
on a goal is another.
link |
Just want to briefly mention one little aside there
link |
because I've got a friend who's a physician.
link |
He's a cardiologist who has a really interesting theory.
link |
This is just theory,
link |
but I think it will resonate with a lot of people,
link |
which is that you've all heard of this molecule dopamine
link |
that gives us this sense of reward
link |
when we accomplish something.
link |
Well, we also want to be able to access dopamine
link |
while we're working towards things.
link |
Enjoy the process, as they say,
link |
because it has all sorts of positive effects.
link |
It gives us energy, et cetera.
link |
With my friend, what he says is,
link |
there's many, many instances
link |
where someone will come to him and say,
link |
you know what, I'm going to write a book.
link |
And he says, oh, that's great.
link |
I'm sure the book's going to be terrific
link |
and you really should write a book.
link |
And then they never go do it.
link |
And his theory is if you get so much dopamine
link |
from the reward of people saying,
link |
oh yeah, you're absolutely going to be able to do that,
link |
you might not actually go after
link |
the reward of the accomplishment itself.
link |
So beware these positive reinforcements also.
link |
Not saying people should flagellate themselves
link |
to the point of victory in whatever they're pursuing,
link |
but motivation is a tricky one.
link |
So I suggest that everyone ask themselves,
link |
what is it that I want to accomplish?
link |
And what is it that's driving me to accomplish this?
link |
And come up with two or three things,
link |
fear-based perhaps, love-based perhaps,
link |
or perhaps several of those,
link |
in order to ensure alertness,
link |
energy and attention for the task.
link |
And that brings us to the attention part.
link |
Now it's one thing to have an electrode
link |
embedded into your brain
link |
and increase the amount of acetylcholine.
link |
It's another to exist in the real world
link |
outside the laboratory and have trouble focusing,
link |
having trouble bringing your attention
link |
to a particular location and space for a particular event.
link |
And there's a lot of discussion nowadays
link |
about smartphones and devices
link |
creating a sort of attention deficit,
link |
almost at a clinical level for many people,
link |
I think that's largely true.
link |
And what it means however,
link |
is that we all are responsible for learning
link |
how to create depth of focus.
link |
There are some important neuroscience principles
link |
to get depth of focus.
link |
I want to briefly talk about the pharmacology first,
link |
because I always get asked about this.
link |
People say, what can I take
link |
to increase my levels of acetylcholine?
link |
Well, there are things you can take.
link |
Nicotine is called nicotine
link |
because acetylcholine binds to the nicotinic receptor.
link |
There are two kinds of acetylcholine receptors,
link |
muscarinic and nicotinic,
link |
but the nicotinic ones are involved
link |
in attention and alertness.
link |
I have colleagues,
link |
these are not my kind of like bro science buddies.
link |
I have those friends too.
link |
This is a Nobel prize winning colleague
link |
who choose Nicorette while he works.
link |
He used to be a smoker.
link |
He quit smoking because of fear of lung cancer.
link |
It's like a smart choice,
link |
but he missed the level of focus
link |
that he could bring to his work.
link |
This is somebody who's had a very long career.
link |
And if you ever meet with him,
link |
unfortunately I can't name him.
link |
If you ever meet with him,
link |
what you realize is he choose
link |
about five pieces of Nicorette an hour,
link |
which I am not suggesting people do.
link |
But when I asked him, why are you doing this?
link |
He said, well, increases my alertness and focus.
link |
And also his theory,
link |
and I want to really underscore that it's theory
link |
not scientifically supported yet
link |
is that it offsets Parkinson's and Alzheimer's.
link |
It is true that nucleus basalis is the primary site
link |
of degeneration in the brain
link |
in people that have dementia and Parkinson's.
link |
And it's what leads to a lot of their inability
link |
to focus their attention,
link |
not just deficits in plasticity.
link |
So he might be onto something.
link |
Now I've tried chewing Nicorette.
link |
It makes me super jittery.
link |
I don't like it because I can't focus very well.
link |
It kind of takes me too far up
link |
the level of autonomic arousal.
link |
I've got friends that dip Nicorette all day,
link |
some of whom are scientists.
link |
Writers and artists and musicians
link |
are familiar with the effects of nicotine
link |
from the era where a lot of people smoked
link |
and fortunately fewer people smoke now.
link |
So if you're interested in the pharmacology,
link |
there are supplements and things
link |
that can increase cholinergic transmission in the brain.
link |
I'm not suggesting you do this,
link |
but if you're gonna go down that route,
link |
you want to be very careful
link |
how much you rely on those all the time
link |
because the essence of plasticity
link |
is to create a window of attention and focus
link |
that's distinct from the rest of your day.
link |
That's what's going to create a mark in your brain
link |
and the potential for plasticity.
link |
Things that increase acetylcholine
link |
besides nicotine or Nicorette,
link |
so the nicotine could come from a variety of sources,
link |
or things like alpha-GPC or choline.
link |
There are a number of these things.
link |
I would encourage you to go to examine.com, the website,
link |
and just put in acetylcholine
link |
and it will give you a list of supplements
link |
as well as some of the dangers of these supplements
link |
that are associated with cholinergic transmission.
link |
But I would be remiss and I would be lying
link |
if I didn't say that there are a lot of people out there
link |
who are using cholinergic drugs
link |
in order to increase their level of focus.
link |
And since we're coming up on the Olympics,
link |
I don't want to get anyone in trouble,
link |
but I'm well aware that the fact that the sprinters
link |
are really into cholinergic drugs
link |
because not only is acetylcholine important for the focus
link |
that allows them to hear the gun
link |
and be first out the blocks on the sprints,
link |
that's a lot of where the race is won,
link |
hearing that gun and being quickest on reaction time,
link |
so they take cholinergic agents for that,
link |
as well as acetylcholine is the molecule
link |
that controls nerve to muscle contraction.
link |
So your speed of reflexes is actually controlled
link |
by this nicotinic transmission as well.
link |
So lots to think about in terms of acetylcholine in sport
link |
and mental acuity, not just plasticity.
link |
Now, for most of you,
link |
you probably don't want to chew Nicorette,
link |
definitely don't want to smoke cigarettes
link |
or take supplements for increasing acetylcholine.
link |
So what are some ways that you can increase acetylcholine?
link |
And there, it's going to sound like a bit
link |
of a circular argument, but you want to increase focus.
link |
How do you increase focus?
link |
You know, people are so familiar with sitting down,
link |
reading a couple pages of a book
link |
and realizing that none of it sunk in
link |
or talking to someone and seeing their mouth move,
link |
maybe even nodding your head subconsciously
link |
and you come, mm-hmm, mm-hmm, and none of it sinks in.
link |
This can be very damaging for school, work performance
link |
and relationships, as many of you know.
link |
Costello, incidentally, never seems to pay attention
link |
to anything I say while looking directly at me,
link |
which contradicts what I'm about to say,
link |
which is that the best way to get better at focusing
link |
is to use the mechanisms of focus that you were born with.
link |
And the key principle here is that mental focus
link |
follows visual focus.
link |
We are all familiar with the fact that our visual system
link |
can be unfocused, blurry, or jumping around,
link |
or we can be very laser focused on one location in space.
link |
What's interesting and vitally important to understanding
link |
how to access neuroplasticity
link |
is that you can use your visual focus
link |
and you can increase your visual focus
link |
as a way of increasing your mental focus abilities
link |
So I'm gonna explain how to do that.
link |
Plasticity starts with alertness.
link |
And as I mentioned before,
link |
that alertness can come from a sense of love,
link |
a sense of joy, a sense of fear, doesn't matter.
link |
There are pharmacologic ways to access alertness too.
link |
The most common one is of course caffeine,
link |
which if you watch the sleep episodes,
link |
you know reduces this molecule
link |
that makes us sleepy called adenosine.
link |
I drink plenty of caffeine.
link |
I'm a heavy user of caffeine.
link |
I don't think abuser of caffeine.
link |
I think in reasonable amounts,
link |
provided we can still fall asleep at night.
link |
Caffeine can be a relatively safe way
link |
to increase epinephrine.
link |
Now, many people are now also using Adderall.
link |
Adderall chemically looks a lot like amphetamine.
link |
And basically it is amphetamine.
link |
It will increase epinephrine release from locus coeruleus.
link |
It will wake up the brain.
link |
And that's why a lot of people rely on it.
link |
It does have a heavy basis for use
link |
in certain clinical syndromes prescribed
link |
such as attention deficit.
link |
However, it also has a high probability of abuse,
link |
especially in those who are not prescribed it.
link |
Adderall will not increase focus.
link |
It increases alertness.
link |
It does not touch the acetylcholine system.
link |
And if those of you that are taking Adderall say,
link |
well, it really increases my focus overall,
link |
that's probably because your autonomic nervous system
link |
is just veering towards what we call parasympathetic.
link |
You're really just very sleepy.
link |
And so it's bringing your levels of alertness up.
link |
As I mentioned, Adderall is very problematic
link |
for a number of people.
link |
It can be habit forming.
link |
Learning on Adderall does not always translate
link |
to high performance off or on Adderall at later times.
link |
And the Adderall discussion is a broader one
link |
that perhaps we should have with a psychiatrist
link |
in the room at some point,
link |
because it is a very widely abused drug
link |
at this point in time.
link |
The acetylcholine system and the focus that it brings
link |
is available, as I mentioned, through pharmacology,
link |
but also through these behavioral practices.
link |
And the behavioral practices that are anchored
link |
in visual focus are going to be the ones
link |
that are going to allow you to develop great depth
link |
and duration of focus.
link |
So let's think about visual focus for a second.
link |
When we focus on something visually, we have two options.
link |
We can either look at a very small region of space
link |
with a lot of detail and a lot of precision,
link |
or we can dilate our gaze and we can see big pieces
link |
of visual space with very little detail.
link |
We can't look at everything at high resolution.
link |
This is why we have these,
link |
the pupil more or less relates to the fovea of the eye,
link |
which is the area in which we have the most receptors,
link |
the highest density of receptors that perceive light.
link |
And so our acuity is much better in the center
link |
of our visual field than in our periphery.
link |
It's a simple experiment you can do right now.
link |
If you're listening to this, you can still do it.
link |
You can hold your hands out in front of you,
link |
provided that you're sighted.
link |
You should be able to see how many fingers
link |
you have in front of you.
link |
For me, it's five.
link |
Still got all five fingers, amazingly enough.
link |
If I move my hand off to the side,
link |
I can't see them with precision,
link |
but as I move them back into the center of my visual field,
link |
I can see them with precision.
link |
And that's because the density,
link |
the number of pixels in the center of my visual field
link |
is much higher than it is in the periphery.
link |
When we focus our eyes, we do a couple things.
link |
First of all, we tend to do that
link |
in the center of our visual field,
link |
and our two eyes tend to align
link |
in what's called a vergence eye movement
link |
towards a common point.
link |
The other thing that happens is the lens of our eye moves
link |
so that our brain now no longer sees the entire visual world
link |
but is seeing a small cone of visual imagery.
link |
That was the dog bumping into the wall, forgive me.
link |
That small cone of visual imagery
link |
or soda straw view of the world has much higher acuity,
link |
higher resolution than if I were to look at everything.
link |
Now you say, of course, this makes perfect sense,
link |
but that's about visual attention, not mental attention.
link |
Well, it turns out that focus in the brain
link |
is anchored to our visual system.
link |
I'll talk about blind people in a moment,
link |
but assuming that somebody is sighted,
link |
the key is to learn how to focus better visually
link |
if you want to bring about higher levels
link |
of cognitive or mental focus,
link |
even if you're engaged in a physical task.
link |
Now, there's a remarkable phenomenon in animals
link |
where animals that have their eyes on the side of their head
link |
are scanning the entire visual environment all the time.
link |
They're not focused on anything.
link |
Think you're grazing animals, your cows, your sheep,
link |
your birds, et cetera.
link |
But think about a bird picking up seeds
link |
on the beach or on concrete.
link |
That bird's head is up here.
link |
It's up about a foot off the ground,
link |
or if it's a small bird, about six inches off the ground,
link |
and its eyes are on the side of its head,
link |
and yet it has this tiny beak that can quickly pick up
link |
these little seeds off the ground with immense precision.
link |
Now, if you try to do that by staring off
link |
to the sides of the room and picking up items
link |
in front of you with high precision at that tiny scale,
link |
little tiny objects, you will miss almost every time.
link |
They do it perfectly, and they don't smash their beak
link |
into the ground and damage it.
link |
They do it with beautiful movement acuity also.
link |
So how do they do it?
link |
How do they create this focus or this awareness
link |
of what's in front of them?
link |
It turns out as they lower their head,
link |
their eyes very briefly move inward
link |
in what's called a virgin's eye movement.
link |
Now, their eyes can't actually translocate in their head.
link |
They're fixed in the skull, just like yours and mine are.
link |
But when we move our eyes slightly inward,
link |
maybe you can tell that I'm doing it like so,
link |
basically shortening or making the interpupillary distance,
link |
as it's called, smaller, two things happen.
link |
Not only do we develop a smaller visual window
link |
into the world, but we activate a set of neurons
link |
in our brainstem that trigger the release
link |
of both norepinephrine, epinephrine, and acetylcholine.
link |
Norepinephrine is kind of similar to epinephrine.
link |
So in other words, when our eyes are relaxed in our head,
link |
when we're just kind of looking
link |
at our entire visual environment,
link |
moving our head around, moving through space,
link |
we're in optic flow, things moving past us,
link |
or we're sitting still, we're looking broadly at our space,
link |
When our eyes move slightly inward
link |
toward a particular visual target,
link |
our visual world shrinks,
link |
our level of visual focus goes up,
link |
and we know that this relates to the release
link |
of acetylcholine and epinephrine
link |
at the relevant sites in the brain for plasticity.
link |
Now, what this means is that if you have a hard time
link |
focusing your mind for sake of reading or for listening,
link |
you need to practice, and you can practice,
link |
focusing your visual system.
link |
Now, this works best if you practice
link |
focusing your visual system at the precise distance
link |
from the work that you intend to do for sake of plasticity.
link |
So how would this look in the real world?
link |
Let's say I am trying to concentrate
link |
on something related to, I don't know, science.
link |
I'm reading a science paper,
link |
and I'm having a hard time, it's not absorbing.
link |
I might think that I'm only looking at the paper
link |
that I'm reading, I'm only looking at my screen,
link |
but actually my eyes are probably darting around a bit.
link |
Experiments have been done on this.
link |
Or I'm gathering information from too many sources
link |
in the visual environment.
link |
Now, presumably, because it's me,
link |
I've already had my coffee, I'm hydrated,
link |
I'm well rested, I slept well,
link |
and I still experience these challenges in focusing.
link |
Spending just 60 to 120 seconds
link |
focusing my visual attention on a small window of my screen,
link |
meaning just on my screen with nothing on it,
link |
but bringing my eyes to that particular location
link |
increases not just my visual acuity for that location,
link |
but it brings about an increase in activity
link |
in a bunch of other brain areas that are associated
link |
with gathering information from this location.
link |
So put simply, if you want to improve your ability to focus,
link |
practice visual focus.
link |
Now, if you wear contacts or you wear corrective lenses,
link |
that's fine, you of course would want to use those.
link |
You don't want to take those off and use a blurry image.
link |
The finer the visual image,
link |
and the more that you can hold your gaze
link |
to that visual image,
link |
the higher your levels of attention will be.
link |
Many times on Instagram and here I've been teased
link |
for not blinking very often.
link |
That's actually a practiced thing.
link |
We blink more as we get tired,
link |
which as you hear it, you'll probably just say duh.
link |
As we get tired, the neurons in the brainstem
link |
that are responsible for alertness
link |
and that hold the eyelids open start to falter
link |
and our eyelids start to close.
link |
This is why it's hard,
link |
the words I could barely keep my eyes open,
link |
which may be how you feel right now.
link |
But assuming that you're paying attention and you're alert,
link |
when you're very alert, your eyes are wide.
link |
Your eyes are open.
link |
And as you get tired, your eyelids start to close.
link |
Blinks actually reset our perception of time and space.
link |
This was shown in a beautiful paper in Current Biology.
link |
I'll be sure to post the reference in the notes.
link |
And blinking of course is necessary to lubricate the eyes.
link |
People blink because their eyes might get dry.
link |
But if you can keep focus by blinking less
link |
and by focusing your eyes to a particular location,
link |
that's probably pretty creepy for you to experience
link |
as I'm doing this.
link |
But the more that you can do this,
link |
the more that you can maintain a kind of a cone
link |
or a tunnel of mental focus.
link |
And so I'm sort of revealing my practice,
link |
which is that I've worked very hard through blinking contests
link |
with my 14 year old niece who still beats me every time
link |
and it really bothers me,
link |
but also just through my own self-practice
link |
of learning to blink less and focus my visual attention
link |
on a smaller region of space.
link |
Now for me, that's important
link |
because I'm mainly learning things on a computer screen.
link |
If you're going to be doing sport,
link |
it's quite a bit different
link |
and we can discuss how you might translate that to sport.
link |
In fact, in the next episode,
link |
I'm gonna talk all about how plasticity
link |
and the focus mechanisms relate
link |
to learning of movement practices and coordinated movements.
link |
It's an entire discussion unto itself,
link |
but the same principle holds.
link |
So we need alertness.
link |
You can get that through mental tricks of motivation,
link |
fear or love, whatever it is.
link |
Pharmacology, please do it healthfully.
link |
Caffeine, if that's in your practice.
link |
Certainly want to be well hydrated.
link |
That increases, actually will increase alertness.
link |
Having a very full bladder will increase alertness,
link |
although you don't want your alertness to be so high,
link |
do that, all you can think about it
link |
is the fact that you have to go urinate
link |
because that's very distracting.
link |
You don't want your alertness to go through the roof.
link |
You need focus and visual focus is the primary way
link |
in which we start to deploy these neurochemicals.
link |
Now you may ask, well, what about the experiment
link |
where people were feeling this rotating drum
link |
or listening to the auditory cue,
link |
that doesn't involve vision at all.
link |
Ah, if you look at people who are learning things
link |
with their auditory system,
link |
they will often close their eyes
link |
and that's not a coincidence.
link |
If somebody is listening very hard,
link |
please don't ask them to look you directly in the eye
link |
while also asking that they listen to you.
link |
That's actually one of the worst ways
link |
to get somebody to listen to you.
link |
If you say, now listen to me and look me in the eye,
link |
the visual system will take over
link |
and they'll see your mouth move,
link |
but they're going to hear their thoughts
link |
more they're going to hear what you're saying.
link |
Closing the eyes is one of the best ways
link |
to create a cone of auditory attention.
link |
And this is what low vision or no vision folks do.
link |
They have tremendous capacity to focus their attention
link |
in particular locations.
link |
Incidentally, does anyone know the two animals
link |
that have the best hearing in the world?
link |
The absolute best hearing,
link |
many orders of magnitude better than humans.
link |
Turns out it's the elephant that might not surprise you.
link |
They have huge ears and the moth,
link |
which probably will surprise you.
link |
I didn't even know that moths could hear,
link |
but now it explains why they're so hard to catch.
link |
If you are not sighted,
link |
you learn how to do this with your hearing.
link |
If you're somebody who braille reads,
link |
you learn how to do this with your fingers.
link |
If you look at great piano players like Glenn Gould,
link |
they oftentimes will turn their head to the side.
link |
You think about some of the great musicians
link |
that like Stevie Wonder that were blind, right?
link |
He would look away
link |
because he had no reason to look at the keys,
link |
but oftentimes they'll orient an ear
link |
or one side of their head to the keys on the piano.
link |
As I mentioned before,
link |
people who are non-sighted have better pitch.
link |
So we have these cones of attention that we can devote.
link |
And for most people,
link |
vision is the primary way to train up this focus ability
link |
and these cones of attention.
link |
So you absolutely have to focus
link |
on the thing that you're trying to learn.
link |
And you will feel some agitation
link |
because of the epinephrine in your system.
link |
If you're feeling agitation and it's challenging to focus
link |
and you're feeling like you're not doing it right,
link |
chances are you're doing it right.
link |
And you can practice this ability to stare
link |
for long periods of time without blinking.
link |
I know it's a little eerie for people to watch,
link |
but if your goal is to learn how to control
link |
that visual window for sake of controlling your focus,
link |
it can be an immensely powerful portal
link |
into these mechanisms of plasticity
link |
because we know it engages things like nucleus basalis
link |
and these other brainstem mechanisms.
link |
I get a lot of questions about
link |
attention deficit hyperactivity disorder, ADHD,
link |
and attention deficit disorder.
link |
Some people actually have clinically diagnosed ADD and ADHD.
link |
And if you do, you should certainly work
link |
with a good psychiatrist to try and figure out
link |
the right pharmacology and or behavioral practices for you.
link |
Many people, however, have given themselves
link |
a low grade ADHD or ADD
link |
because of the way that they move through their world.
link |
They are looking at their phone a lot of the time.
link |
It's actually very easy to anchor your attention
link |
to your phone for the following reason.
link |
First of all, it's very restricted in size.
link |
So it's very easy to limit your visual attention
link |
to something about this big.
link |
It's one of the design features of the phone.
link |
The other is that just as you've probably heard,
link |
a picture is worth a thousand words.
link |
Well, a movie is worth 10,000 pictures.
link |
Anytime we're looking at things that have motion,
link |
visual motion, our attentional system
link |
will naturally gravitate towards those movies.
link |
It's actually much harder to read words on a page
link |
than it used to be for many people
link |
because we're used to seeing things spelled out for us
link |
in YouTube videos or videos where things move
link |
and are very dramatic.
link |
It is true that the more that we look
link |
at those motion stimuli,
link |
the more that we're seeing movies of things
link |
and things that are very dramatic and very intense,
link |
the worse we're getting at attending to things
link |
like text on a page or to listening to something
link |
like a podcast and extracting the information.
link |
So much so that I think many people have asked me,
link |
why aren't you providing intense visuals
link |
for us to look at?
link |
Well, frankly, it's because a lot of people
link |
are consuming this content through pure auditory,
link |
through just by listening,
link |
and I want them to be able to digest all the material.
link |
But in addition to that,
link |
if you think about the areas of life
link |
that dictate whether or not we become successful,
link |
independent, healthy individuals,
link |
most of those involve the kind of boring practices
link |
of digesting information on a page.
link |
Boring because it's not as exciting in the moment perhaps
link |
as watching a movie or something being spoonfed to us.
link |
But the more attention that we can put to something,
link |
even if it's fleeting and we feel like
link |
we're only getting little bits and pieces,
link |
shards of the information as opposed to the entire thing,
link |
that has a much more powerful effect
link |
in engaging this cholinergic system for plasticity
link |
than does, for instance, watching a movie.
link |
And that's because when we watch a movie,
link |
the entire thing can be great, it can be awesome,
link |
it can be this overriding experience.
link |
But I think for all those experiences,
link |
if you're somebody who's interested in building your brain
link |
and expanding your brain and getting better
link |
at various things, feeling better, doing better, et cetera,
link |
one has to ask how much of my neurochemical resources
link |
am I devoting to the passive experience
link |
of letting something just kind of overwhelm me and excite me
link |
versus something that I'm really trying
link |
to learn and take away.
link |
And now there's another, I enjoy movie content
link |
and TV content all the time.
link |
I scroll Instagram often, but we are limited
link |
in the extent to which we can grab a hold
link |
of these acetylcholine release mechanisms or epinephrine.
link |
And I think that we need to be careful
link |
that we don't devote all our acetylcholine and epinephrine,
link |
all our dopamine for that matter,
link |
to these passive experiences of things
link |
that are not going to enrich us and better us.
link |
So that's a little bit of an editorial on my part,
link |
but the phone is rich with movies,
link |
it's rich with information.
link |
The real question is, is the information rich for us
link |
in ways that grow us and cultivate smarter,
link |
more emotionally evolved people,
link |
or is it creating, what's it doing
link |
for our physical wellbeing for that matter?
link |
So I don't want to tell people what to do or not to do,
link |
but think carefully about how often you're focusing
link |
on something and how good you are or poor you are
link |
at focusing on something that's challenging.
link |
So once you get this epinephrine, this alertness,
link |
you get the acetylcholine released
link |
and you can focus your attention,
link |
then the question is for how long?
link |
And in an earlier podcast,
link |
I talked about these ultradian cycles
link |
that last about 90 minutes.
link |
The typical learning bout should be about 90 minutes.
link |
I think that learning bout will no doubt include
link |
five to 10 minutes of warmup period.
link |
I think everyone should give themselves permission
link |
to not be fully focused in the early part of that bout,
link |
but that in the middle of that bout,
link |
for the middle hour or so,
link |
you should be able to maintain focus
link |
for about an hour or so.
link |
So that for me means eliminating distractions.
link |
That means turning off the wifi.
link |
I put my phone in the other room.
link |
If I find myself reflexively getting up to get the phone,
link |
I will take the phone and lock it in the car outside.
link |
If I find myself going to get it anyway,
link |
I am guilty of giving away the phone for a period of time
link |
or even things more dramatic.
link |
I've thrown it up on my roof before,
link |
so I can't get to it till the end of the day.
link |
That thing is pretty compelling.
link |
And we come up with all sorts of reasons
link |
why we need it to be in contact with it.
link |
But I encourage you to try experiencing what it is
link |
to be completely immersed in an activity
link |
where you feel the agitation
link |
that your attention is drifting,
link |
but you continually bring it back.
link |
And that's an important point,
link |
which is that attention drifts,
link |
but we have to re-anchor it.
link |
We have to keep grabbing it back.
link |
And the way to do that, if you're sighted,
link |
is with your eyes.
link |
That as your attention drifts and you look away,
link |
you want to try and literally maintain visual focus
link |
on the thing that you're trying to learn.
link |
Feel free to blink, of course,
link |
but you can greatly increase your powers of focus
link |
and the rates of learning,
link |
which is anchored in all the work of Merzinek,
link |
Hubel and Wiesel, and others.
link |
Now that's the trigger for plasticity.
link |
But the real secret is that neuroplasticity
link |
doesn't occur during wakefulness.
link |
It occurs during sleep.
link |
We now know that if you focus very hard on something
link |
for about 90 minutes or so,
link |
maybe you even do several bouts of that per day,
link |
if you can do that, some people can,
link |
some people can only do one focus bout of learning.
link |
That night and the following nights while you sleep,
link |
the neural circuits that were highlighted, if you will,
link |
with acetylcholine transmission will strengthen
link |
and other ones will be lost,
link |
which is wonderful because that's the essence of plasticity.
link |
And what it means is that when you eventually wake up
link |
a couple of days or a week later,
link |
you will have acquired the knowledge forever,
link |
unless you go through some process to actively unlearn it.
link |
And we will talk about unlearning in a later episode.
link |
So mastering sleep is key
link |
in order to reinforce the learning that occurs.
link |
But let's say you get a really poor night of sleep
link |
after a bout of learning.
link |
Chances are if you sleep the next night
link |
or the following night, that learning will occur.
link |
There's a stamp in the brain
link |
where this acetylcholine was released.
link |
It actually marks those synapses neurochemically
link |
and metabolically so that those synapses
link |
are more biased to change.
link |
Now, if you don't ever get that deep sleep,
link |
then you probably won't get those changes.
link |
But there's also a way in which you can bypass the need
link |
for deep sleep, at least partially,
link |
by engaging in what I call non-sleep deep rest,
link |
these NSDR protocols.
link |
But I just want to discuss the science of this.
link |
There was a paper that was published
link |
in Cell Reports last year
link |
that shows that if people did,
link |
it was a spatial memory task,
link |
actually a quite difficult one
link |
where they had to remember the sequence of lights
link |
And if they're just two or three lights
link |
in a particular sequence, it's easy.
link |
But as you get up to 15 or 16 lights
link |
and think numbers in the sequence,
link |
it actually gets quite challenging.
link |
If immediately after,
link |
and it was immediately after the learning,
link |
the actual performance of this task,
link |
people took a 20-minute non-sleep deep rest protocol,
link |
or took a shallow nap,
link |
so lying down, feet slightly elevated perhaps,
link |
just closing their eyes, no sensory input,
link |
the rates of learning were significantly higher
link |
for that information
link |
than were to just had a good night's sleep
link |
the following night.
link |
So you can actually accelerate learning
link |
with these NSDR protocols
link |
or with brief naps, 90 minutes or less.
link |
So the key to plasticity in childhood is to be a child.
link |
The key to plasticity in adulthood
link |
is to engage alertness, engage focus,
link |
and then to engage non-sleep deep rest
link |
and deep sleep while you're in your typical bout of sleep.
link |
I always get asked, how many bouts of learning
link |
Well, I know people that train up
link |
these visual focus mechanisms
link |
to the point where they can do several 90-minute bouts
link |
throughout the day, as many as three or four.
link |
And some of them are also inserting
link |
non-sleep deep rest as well.
link |
Now that can get pretty tricky.
link |
A lot of people find that they can recover best
link |
from these intense bouts of focused learning
link |
by doing some motor activity,
link |
where you get into self-generated optic flow.
link |
And that should make sense
link |
if you've ever heard me lecture about stress,
link |
which I've done a little bit in various podcasts.
link |
When we are in a mode of self-generated optic flow
link |
like walking or running or cycling
link |
and things are just floating past us on our retina,
link |
we're not really looking anywhere in particular.
link |
So this is the opposite of a tight window of focus.
link |
When we do that, there are areas of the brain
link |
like the amygdala, which are involved
link |
in releasing epinephrine and create alertness.
link |
At the extremes, it creates fear, but certainly alertness.
link |
Those all shut down.
link |
So it's its own form of non-sleep deep rest.
link |
So some people find it much more pleasurable and practical
link |
to engage in a focused bout of learning
link |
and then go do some activity that involves
link |
what we would essentially call wordlessness,
link |
where you're not really thinking about much of anything.
link |
And so for those of you that listen to audio books
link |
or podcasts while you run,
link |
you may want to consider whether or not
link |
that's how you want to spend your time.
link |
Now, I'd love it if you were listening to this podcast
link |
while you run or cycle, but I'm much more interested
link |
in you actually getting the benefits of neuroplasticity
link |
than just listening to me for sake of listening to me.
link |
So for many people, letting the mind drift
link |
where it's not organized in thought
link |
after a period of very deliberate focused effort
link |
is the best way to accelerate learning
link |
and depth of learning.
link |
And there are good scientific data
link |
to support these sorts of things,
link |
including the cell reports paper
link |
that I mentioned a few moments ago.
link |
I want to synthesize some of the information
link |
that we've covered up until now.
link |
This entire month is about neuroplasticity.
link |
Today's episode has covered a lot,
link |
but by no means has it covered all of the potential
link |
for neuroplasticity and protocols for plasticity.
link |
We will get into all of it.
link |
But today I want to make sure that these key elements
link |
that form the backbone of neuroplasticity
link |
are really embedded in people's minds.
link |
First of all, plasticity occurs throughout the lifespan.
link |
Early from birth until 25,
link |
mere exposure to a sensory event can create plasticity.
link |
That could be a good thing or a bad thing.
link |
We're going to talk about unlearning the bad stuff,
link |
traumas, et cetera, in a subsequent episode this month.
link |
If you want to learn as an adult, you have to be alert.
link |
It might seem so obvious,
link |
but I think a lot of people don't think about
link |
when in their 24 hour cycle they're most alert.
link |
There are four episodes devoted to that 24 hour cycle
link |
and the cycles of alertness and sleep.
link |
I encourage you to listen to those
link |
if you haven't had the opportunity to yet,
link |
or just ask yourself when during the day
link |
do you typically tend to be most alert.
link |
That will afford you an advantage
link |
in learning specific things during that period of time.
link |
So don't give up that period of time
link |
for things that are meaningless, useless,
link |
or not aligned with your goals.
link |
That'd be a terrible time to get into passive observance
link |
or just letting your time get soaked away by something.
link |
That is a valuable asset.
link |
That epinephrine released from your brainstem
link |
is going to occur more readily at particular phases
link |
of your 24 hour cycle than others,
link |
during the waking phase, of course.
link |
You should know when those are.
link |
And then you could start to think about
link |
the behavioral practices,
link |
maybe the pharmacologic practices like caffeine,
link |
hydration, et cetera,
link |
that will support heightened levels of alertness.
link |
Attention is something that can be learned
link |
and attention is critical for creating that condition
link |
where whatever it is that you are engaging in
link |
will modify your brain in a way
link |
that you won't have to spend so much attention on it
link |
That's the essence of plasticity,
link |
that things will eventually become reflexive,
link |
the language that you're learning,
link |
the motor movement, the cognitive skill,
link |
the ability to suppress an emotional response
link |
or to engage in emotional response,
link |
depending on what your goals are
link |
and what's appropriate for you.
link |
Increasing acetylcholine can be accomplished
link |
pharmacologically through nicotine.
link |
However, there are certain dangers
link |
for many people to do that,
link |
as well as a cost, a financial cost.
link |
Learning how to engage the cholinergic system
link |
through the use of the visual system.
link |
Practicing how long can you maintain focus
link |
with blanks as you need them,
link |
but how long can you maintain visual focus on a target,
link |
just on a piece of paper set a few feet away in the room
link |
or at the level of your computer screen.
link |
These are actually things that people do in communities
link |
where high levels of visual focus are necessary.
link |
Now, the other way to get high levels of visual focus
link |
and alertness is to have a panic
link |
or to have a situation that's very, very bad.
link |
You will be immediately focused on everything
link |
related to that situation, but that's unfortunate.
link |
What we're really talking about here
link |
is trying to harness the mechanisms of attention
link |
and get better at paying attention.
link |
You may want to do that with your auditory system,
link |
not with your visual system,
link |
either because you're low vision or no vision,
link |
or because you're trying to learn something
link |
that relates more to sounds than to what you see.
link |
But for most people,
link |
they're trying to learn information, cognitive information,
link |
or they're trying to learn how to hear the nuance
link |
in their partner's explanations
link |
of their emotionally challenging events, et cetera.
link |
And just remember, by the way, what I said earlier,
link |
which is that if you really want somebody to listen to you
link |
and really hear what you're saying and what's underlying it,
link |
you should not and cannot expect them
link |
to look directly at you while you do that.
link |
That's actually going to limit their ability to focus.
link |
I'm trying to rescue a few folks out there
link |
who might be in this struggle.
link |
I, of course, have never been in this struggle.
link |
And that was supposed to be a joke.
link |
I'm very familiar with that struggle.
link |
But I know that one can get better at listening.
link |
One can get better at learning.
link |
One can get better at all sorts of things
link |
by anchoring in these mechanisms.
link |
Now, of course, you can also combine protocols.
link |
You can decide to combine pharmacology
link |
with these learning practices.
link |
Many people in communities do that.
link |
Many people are doing that naturally
link |
by drinking their coffee right before they do their learning.
link |
But I would also encourage you to think about
link |
how long those learning bouts are.
link |
If you think you have an ADD or ADHD,
link |
see a clinician, but you should also ask yourself,
link |
are you giving up the best period of focus
link |
that you have each day naturally
link |
to some other thing like social media
link |
or some other activity that doesn't serve you well?
link |
Or are you devoting that period to the opportunity to learn?
link |
You should also ask yourself
link |
whether or not you're trying to focus too much
link |
for too long during the day.
link |
I know some very high-performing individuals,
link |
very high-performing in a variety of contexts,
link |
and none of them are focused all day long.
link |
Many of them take walks down the hallway,
link |
sometimes mumbling to themselves
link |
or not paying attention to anything else.
link |
They go for bike rides, they take walks.
link |
They are not trying to engage their mind
link |
at maximum focus all the time.
link |
Very few people do that because we learn best
link |
in these 90-minute bouts
link |
inside of one of these ultradian cycles.
link |
And I should repeat again
link |
that within that 90-minute cycle,
link |
you should not expect yourself to focus
link |
for the entire period of one 90-minute cycle.
link |
At the beginning and end
link |
are going to be a little bit flickering in and out of focus.
link |
How do you know when one of these 90-minute cycles
link |
Well, typically when you wake up
link |
is the beginning of the first 90-minute cycle,
link |
but it's not down to the minute.
link |
You'll be able to tap into your sense
link |
of these 90-minute cycles
link |
as you start to engage in these learning practices
link |
should you choose.
link |
And then of course, getting some non-sleep deep rest
link |
or just deliberate disengagement
link |
such as walking or running
link |
or just sitting eyes closed or eyes open kind of mindlessly,
link |
it might seem in a chair,
link |
just letting your thoughts move around
link |
after a learning bout will accelerate
link |
the rate of plasticity
link |
that's been shown in quality peer-reviewed studies.
link |
And then of course, deep sleep.
link |
And so what we can start to see is that
link |
plasticity is your natural right early in life,
link |
but after about age 25,
link |
you have to do some work in order to access it.
link |
But fortunately, these beautiful experiments
link |
of Hubel and Wiesel and Merzenich and Weinberger and others
link |
point in the direction of what allows us
link |
to achieve plasticity.
link |
It points to the neurochemicals and the circuits.
link |
And we now have behavioral protocols
link |
that allow us to do that.
link |
I also really want to emphasize
link |
that there's an entire other aspect of behavioral practices
link |
that will allow us to engage in plasticity
link |
that don't involve intense focus and emotionality,
link |
but involve a lot of repetition.
link |
So there's another entire category of plasticity
link |
that involves doing what seemed like almost mundane things,
link |
but doing them over and over again repeatedly
link |
and incorporating the reward system that involves dopamine.
link |
So today I talked about the kind of plasticity
link |
that comes from extreme focus.
link |
You would get that extreme focus and alertness naturally
link |
through a hard or difficult event that you didn't want.
link |
That's the kind of stinger,
link |
but your brain is designed to keep you safe.
link |
So it wants to get one trial learning
link |
from things like touching a hot stove
link |
or engaging with a really horrible person.
link |
You can get incredible plasticity of positive experiences
link |
of things that you want by engaging this high focus regime
link |
and then rest, non-sleep deep rest and sleep.
link |
And there's another aspect of plasticity
link |
which we will explore next episode
link |
as well as when we explore movement-based practices
link |
for enhancing plasticity and plasticity of movement itself.
link |
And those are not of the high attention,
link |
kind of high emotionality
link |
or the intensity of the experiences that I described today,
link |
those are more about repetition and reward and repeat,
link |
repetition, reward, repeat.
link |
And they are used for a distinctly different category
link |
of behavioral change, more of which relate to habits
link |
as opposed to learning of particular types of information
link |
that allow us to perform physically, cognitively
link |
or adjust our emotional system.
link |
So I'm going to stop there.
link |
I'm sure there are a lot of questions.
link |
Please put your questions in the comment section below
link |
and please remember that this entire month
link |
we're going to be exploring neuroplasticity.
link |
So this discussion slash lecture,
link |
I wish it was more of a back and forth
link |
but this is what the format offers us.
link |
So please do put your questions in the comment section
link |
and I will address them in the other episodes coming soon
link |
on neuroplasticity.
link |
As I say that, I'm reminded that many of you
link |
are listening to this on Apple or Spotify
link |
and therefore there isn't an opportunity to leave comments
link |
aside from the rating section on Apple.
link |
So if you have specific topics related to neuroplasticity
link |
that you would like me to cover
link |
in the subsequent episodes this month,
link |
please go to the YouTube, subscribe,
link |
but as well, please put your question
link |
in the comment section for this episode
link |
and I'll be sure to read them and respond.
link |
Many of you have very graciously asked
link |
how you can help support the Huberman Lab Podcast.
link |
Best way to do that is to subscribe on YouTube.
link |
You might want to also hit the notification button
link |
so that you don't miss any upcoming episodes.
link |
As well, if you go to Apple,
link |
you can give us a five-star rating
link |
and there's a place there where also you can leave a comment
link |
and if you prefer to listen on Spotify,
link |
subscribe and download on Spotify.
link |
In addition, it's always helpful if you recommend the podcast
link |
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link |
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link |
and as well, please check out our sponsors.
link |
That's a great way to help us.
link |
Today and in previous episodes,
link |
I've talked a number of times about supplements.
link |
I'm very pleased that we're partnering
link |
with Thorne, T-H-O-R-N-E supplements
link |
because Thorne has the very high levels of stringency
link |
in terms of product quality and precision
link |
about how much of given supplements are in the bottle,
link |
which is vital and not all supplement companies
link |
have stood up to the test on that one.
link |
If you wanna check out Thorne and go to Thorne,
link |
that's thorne.com slash U slash Huberman
link |
and if you do that,
link |
you'll get 20% off any supplements that you purchase.
link |
I've also listed there a gallery of supplements that I take
link |
including magnesium glycinate.
link |
I know in previous episodes,
link |
I talked about magnesium threonate as a sleep aid
link |
Magnesium glycinate and magnesium threonate
link |
are essentially interchangeable.
link |
Thanks so much for your time and attention
link |
thank you for your interest in science.
link |
I'll see you in the next one.