back to indexHow Your Nervous System Works & Changes | Huberman Lab Podcast #1
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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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I'm 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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For today's podcast,
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we're going to talk about the parts list
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of the nervous system.
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Now that might sound boring,
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but these are the bits and pieces that together
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make up everything about your experience of life,
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from what you think about to what you feel,
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what you imagine, and what you accomplish
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from the day you're born until the day you die.
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That parts list is really incredible
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because it has a history associated with it
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that really provides a window into all sorts of things
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like engineering, warfare, religion, and philosophy.
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So I'm gonna share with you the parts list
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that makes up who you are
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through the lens of some of those other aspects of life
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and other aspects of the history of the discovery
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of the nervous system.
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By the end of this podcast,
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I promise you're gonna understand a lot more
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about how you work and how to apply that knowledge.
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There's gonna be a little bit of story.
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There's gonna be a lot of discussion about the people
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who made these particular discoveries.
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There'll be a little bit of technical language.
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There's no way to avoid that.
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But at the end, you're gonna have in hand
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what will be the equivalent of an entire semester
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of learning about the nervous system and how you work.
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So a few important points before we get started.
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I am not a medical doctor.
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That means I don't prescribe anything.
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So sometimes I'll profess things.
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In fact, I profess a lot of things.
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We are going to talk about some basic functioning
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of the nervous system, parts, et cetera.
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But we're also gonna talk about how to apply that knowledge.
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That said, your healthcare,
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your wellbeing is your responsibility.
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So anytime we talk about tools,
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please filter it through that responsibility.
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Talk to a healthcare professional
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if you're gonna explore any new tools or practices.
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And be smart in your pursuit of these new tools.
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I also wanna emphasize that this podcast
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and the other things I do on social media
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are my personal goal of bringing zero cost
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to consumer information to the general public.
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It is separate from my role at Stanford University.
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In that spirit, I really wanna thank the sponsors
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of today's podcast.
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The first one is Athletic Greens,
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which is an all-in-one drink.
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It's a greens drink that has vitamins, minerals,
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probiotics, prebiotics.
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I've been using Athletic Greens since 2012.
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So I'm really delighted that they're sponsoring the podcast.
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The reason I like it is because
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I like vitamins and minerals.
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I think they're important to my health
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and it can be kind of overwhelming to know
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what to take in that landscape.
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So by taking one thing that also happens to taste really
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good, I get all the vitamins, minerals, et cetera
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There's also a lot of data out there now
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about the importance of the gut microbiome
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for immune health and for the gut brain access,
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And the probiotics and prebiotics are important to me
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If you wanna try Athletic Greens,
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you can go to athleticgreens.com slash Huberman
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and put in the code word Huberman at checkout.
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If you do that, they'll send you a year supply
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of vitamin D3 and K2.
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There's a lot in the news lately
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about the importance of vitamin D3.
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We can all get vitamin D3 from sunlight,
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but many of us aren't getting enough sunlight.
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Vitamin D3 has been shown to be relevant
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to the immune system and the hormone systems, et cetera.
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So once again, that's athleticgreens.com slash Huberman,
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enter Huberman at checkout and you get the year supply
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of D3 and K2 along with your Athletic Greens.
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This podcast is also brought to us by Inside Tracker,
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which is a health monitoring company.
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It uses blood tests and saliva tests
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to look at things like DNA and metabolic markers
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and monitors your hormones,
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a huge number of different parameters of health
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that really can only be measured accurately
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through blood and saliva tests.
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I use Inside Tracker because I'm a big believer in data.
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There's a lot of aspects to our biology
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that can only be accurately measured
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by way of blood test and saliva test.
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The thing that's really nice about Inside Tracker
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is that rather than just giving you a bunch of numbers back
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of the levels of these things in your body,
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it gives you through a really simple platform information
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about what to do with all those levels of hormones
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and metabolic markers, et cetera.
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It also has a feature which is particularly interesting,
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which it measures your inner age,
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which is more a measure of your biological age
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as opposed to your chronological age.
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And all that information is organized
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so that you can make changes in your nutritional regimes
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or your exercise regimes
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and watch how those markers change over time.
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So if you wanna try Inside Tracker,
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you can go to insidetracker.com slash Huberman
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and they'll give you 25% off at checkout.
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So let's talk about the nervous system.
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The reason I say your nervous system and not your brain
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is because your brain is actually just one piece
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of this larger, more important thing, frankly,
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that we call the nervous system.
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The nervous system includes your brain and your spinal cord,
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but also all the connections between your brain
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and your spinal cord and the organs of your body.
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It also includes, very importantly,
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all the connections between your organs
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back to your spinal cord and brain.
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So the way to think about how you function at every level
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from the moment you're born until the day you die,
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everything you think and remember and feel and imagine
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is that your nervous system is this continuous loop
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of communication between the brain, spinal cord and body
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and body, spinal cord and brain.
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In fact, we really can't even separate them.
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It's one continuous loop.
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You may have heard of something called a Mobius strip.
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A Mobius strip is almost like one of these impossible figures
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that no matter which angle you look at it from,
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you can't tell where it starts and where it ends.
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And that's really how your nervous system is built.
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That's the structure that allows you to, for instance,
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deploy immune cells, to release cells
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that will go kill infection
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when you're in the presence of infection.
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Most people just think about that
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as a function of the immune system,
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but actually it's your nervous system
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that tells organs like your spleen to release killer cells
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that go and hunt down those bacterial and viral invaders
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and gobble them up.
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If you have a stomach ache, for instance,
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sure, you feel that in your stomach,
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but it's really your nervous system
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that's causing the stomach ache.
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The ache aspect of it is a nervous system feature.
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So when we wanna talk about experience
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or we wanna talk about how to change the self in any way,
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we really need to think about the nervous system first.
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It is fair to say that the nervous system
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governs all other biological systems of the body
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and it's also influenced by those other biological systems.
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So if we're talking about the nervous system,
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we need to get a little specific about what we mean.
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It's not just this big loop of wires.
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In fact, there's a interesting story about that
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because at the turn of the sort of 1800s to 1900s,
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it actually was believed that our nervous system
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was just one giant cell.
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But two guys, the names aren't super important,
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but in fairness to their important discovery,
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Ramon y Cajal, a Spaniard, Camillo Golgi, an Italian guy,
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figured out how to label or stain the nervous system
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in a way that revealed, oh my goodness,
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we're actually made up of trillions of these little cells,
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nerve cells that are called neurons.
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And that's what a neuron is, it's just a nerve cell.
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They also saw that those nerve cells
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weren't touching one another.
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They're actually separated by little gaps
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and those little gaps you may have heard of before,
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they're called synapses.
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Those synapses are where the chemicals from one neuron
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are kind of spit out or vomited into
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and then the next nerve cell detects those chemicals
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and then passes electricity down its length
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to the next nerve cell and so forth.
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So really the way to think about your body
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and your thoughts and your mind
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is that you are a flow of electricity, right?
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There's nothing mystical about this.
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You're a flow of electricity
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between these different nerve cells
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and depending on which nerve cells are active,
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you might be lifting your arm or lowering your arm.
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You might be seeing something and perceiving that it's red
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or you might be seeing something and perceiving that
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it's green all depending on which nerve cells
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are electrically active at a given moment.
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The example of perceiving red or perceiving green
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is a particularly good example
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because so often our experience of the world
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makes it seem as if these things that are happening
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outside us are actually happening inside us.
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But the language of the nervous system is just electricity.
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It's just like a Morse code of some sort
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or the syllables and words and consonants
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and vowels of language.
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It just depends on how they're assembled, what order.
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And so that brings us to the issue
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of how the nervous system works.
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The way to think about how the nervous system works
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is that our experiences, our memories, everything
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is sort of like the keys on a piano
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being played in a particular order, right?
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If I play the keys on a piano in a particular order
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and with a particular intensity, that's a given song.
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We can make that analogous to a given experience.
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It's not really that the key A-sharp or E-flat is the song.
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It's just one component of the song.
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So when you hear that, for instance,
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there's a brain area called the hippocampus,
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which there is, that's involved in memory.
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Well, it's involved in memory,
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but it's not that memories are stored there as sentences.
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They're stored there as patterns of electricity and neurons
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that when repeated give you the sense
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that you are experiencing the thing again.
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In fact, deja vu, the sense that what you're experiencing
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is so familiar and like something
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that you've experienced previously
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is merely that the neurons that were active
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in one circumstance are now becoming active
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in the same circumstance again.
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And so it's really just like hearing the same song
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maybe not played on a piano,
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but next time on a classical guitar,
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there's something similar about that song,
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even though it's being played on two different instruments.
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So I think it's important that people understand
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the parts of their nervous system
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and that it includes so much more than just the brain
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and that there are these things, neurons and synapses,
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but really that it's the electrical activity of these neurons
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that dictates our experience.
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So if the early 1900s
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were when these neurons were discovered,
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certainly a lot has happened since then.
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And in that time between the early 1900s and now,
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there's some important events that actually happened
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in history that give us insight
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or gave us insight into how the nervous system works.
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One of the more surprising ones was actually warfare.
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So as most everybody knows in warfare,
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people get shot and people often die,
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but many people get shot and they don't die.
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And in World War I,
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there were some changes in artillery, in bullets,
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that made for a situation where bullets would enter
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the body and brain at very discreet locations
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and would go out the other side of the body or brain
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and also make a very small hole at that exit location.
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And in doing so produced a lot of naturally occurring
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lesions of the nervous system.
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Now you say, okay, well, how does that relate
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Well, unlike previous years where a lot of the artillery
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would create these big sort of holes
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as the bullets would blow out of the brain or body,
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I know this is rather gruesome,
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when the holes were very discreet,
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they entered at one point and left at another point,
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they would take out or destroy very discreet bits
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of neural tissue of the nervous system.
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So people were coming back from war
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with holes in their brain and in other parts
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of their nervous system that were limited
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to very specific locations.
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In addition to that, there was some advancement
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in the cleaning of wounds that happened,
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so many more people were surviving.
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What this meant was that neurologists now had a collection
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of patients that would come back and they'd have holes
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in very specific locations of their brain
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and they'd say things like, well, I can recognize faces,
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but I can't recognize who those faces belong to.
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I know it's a face, but I don't know who it belongs to.
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And after that person eventually died,
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the neurologist would figure out,
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ah, I've had 10 patients that all told me
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that they couldn't recognize faces
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and they all had these bullet holes
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that went through a particular region of the brain
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and that's how we know a lot
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about how particular brain regions like the hippocampus work.
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In fact, some of the more amazing examples of this
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where people would come back and they, for instance,
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would speak in complete gibberish,
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whereas previously they could speak normally.
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And even though they were speaking in complete gibberish,
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they could understand language perfectly.
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That's how we know that speech and language
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are actually controlled by separate portions
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of the nervous system.
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And there are many examples like that,
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people that couldn't recognize the faces of famous people.
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Or, and that actually brings us to an interesting example
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Many, many years later in the early 2000s,
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there was actually a paper that was published
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in the journal Nature, excellent journal,
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showing that in a human being,
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a perfectly healthy human being,
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there was a neuron that would become active,
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electrically active only when the person viewed
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the picture of Jennifer Aniston, the actress.
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So literally a neuron that represented Jennifer Aniston,
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so-called Jennifer Aniston cells.
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Neuroscientists know about these Jennifer Aniston cells.
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If you can recognize Jennifer Aniston's face,
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you have Jennifer Aniston neurons
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and presumably also have neurons that can recognize
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the faces of other famous and non-famous people.
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So that indicates that our brain is really a map
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of our experience.
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We come into the world and our brain has a kind of bias
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towards learning particular kinds of things.
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It's ready to receive information
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and learn that information,
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but the brain is really a map of experience.
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So let's talk about what experience really is.
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What does it mean for your brain to work?
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Well, I think it's fair to say
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that the nervous system really does five things, maybe six.
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The first one is sensation.
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So this is important to understand for any and all of you
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that want to change your nervous system
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or to apply tools to make your nervous system work better.
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Sensation is a non-negotiable element
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of your nervous system.
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You have neurons in your eye that perceive
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certain colors of light and certain directions of movement.
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You have neurons in your skin
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that perceive particular kinds of touch,
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like light touch or firm touch or painful touch.
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You have neurons in your ears that perceive certain sounds.
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Your entire experience of life is filtered
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by these what we call sensory receptors,
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if you want to know what the name is.
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So this always raises an interesting question.
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People ask, well, is there much more out there?
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Is there a lot more happening in the world
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that I'm not experiencing or that humans aren't experiencing?
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And the answer of course is yes.
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There are many species on this planet
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that are perceiving things that we will never perceive
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unless we apply technology.
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The best example I could think of off the top of my head
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would be something like infrared vision.
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There are snakes out there, pit vipers and so forth
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that can sense heat emissions from other animals.
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They don't actually see their shape.
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They sense their heat shape and their heat emissions.
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Humans can't do that unless of course
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they put on infrared goggles or something
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that would allow them to detect those heat emissions.
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There are turtles and certain species of birds
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that migrate long distances that can detect magnetic fields
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because they have neurons.
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Again, it's the nervous system that allows them to do this.
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So they have neurons in their nose and in their head
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that allow them to migrate along magnetic fields
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in order to, as amazing as this sounds,
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go from one particular location in the ocean,
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thousands of miles away to all aggregate
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on one particular beach at a particular time of year
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so that they can mate, lay eggs
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and then wander back off into the sea to die
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and then their young will eventually hatch.
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Those cute little turtles will shuffle to the ocean,
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swim off and go do the exact same thing.
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They don't migrate that distance by vision.
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They don't do it by smell.
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They do it by sensing magnetic fields, okay?
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And many other species do these incredible things.
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We don't, humans are not magnetic sensing organisms.
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We can't do that because we don't have receptors
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that sense magnetic fields.
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There are some data that maybe some humans
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can sense magnetic fields,
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but you should be very skeptical of anyone
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that's convinced that they can do that
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with any degree of robustness or accuracy
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because even the people that can do this
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aren't necessarily aware that they can.
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Maybe a topic for a future podcast.
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So we have sensation.
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Then we have perception.
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Perception is our ability to take what we're sensing
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and focus on it and make sense of it,
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to explore it, to remember it.
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So really perceptions are just whichever sensations
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we happen to be paying attention to at any moment.
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And you can do this right now.
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You can experience perception
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and the difference between perception
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and sensation very easily.
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If for instance, I tell you to pay attention
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to the contact of your feet, the bottoms of your feet
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with whatever surface they happen to be in contact with,
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maybe it's shoes, maybe it's the floor.
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If your feet are up, maybe it's air.
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The moment you place your,
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what we call the spotlight of attention
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or the spotlight of perception on your feet,
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you are now perceiving what was happening there,
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what was being sensed there.
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The sensation was happening all along, however.
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So while sensation is not negotiable,
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you can't change your receptors
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unless you adopt some new technology.
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Perception is under the control of your attention.
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And the way to think about attention
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is it's like a spotlight, except it's not one spotlight.
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You actually have two attentional spotlights.
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Anyone that tells you you can't multitask,
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tell them they're wrong.
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And if they disagree with you, tell them to contact me.
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Because in old world primates of which humans are,
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we are able to do what's called covert attention.
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We can place a spotlight of attention on something.
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For instance, something we're reading or looking at,
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or someone that we're listening to.
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And we can place a second spotlight of attention
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on something we're eating and how it tastes,
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or our child running around in the room or my dog.
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You can split your attention into two locations,
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but of course you can also bring your attention,
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that is your perception, to one particular location.
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You can dilate your attention,
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kind of like making a spotlight more diffuse,
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or you can make it more concentrated.
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This is very important to understand
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if you're going to think about tools
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to improve your nervous system,
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whether or not that tool is in the form of a chemical
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that you decide to take,
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maybe a supplement to increase some chemical in your brain,
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if that's your choice, or a brain machine device,
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or you're going to try and learn something better
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by engaging in some focus or motivated pursuit
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for some period of time each day.
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Attention is something that is absolutely under your control,
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in particular, when you're rested.
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And we'll get back to this, but when you are rested,
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and we'll define rest very clearly,
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you are able to direct your attention
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in very deliberate ways.
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And that's because we have something in our nervous system
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which is sort of like a two-way street.
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And that two-way street is a communication
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between the aspects of our nervous system
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that are reflexive and the aspects of our nervous system
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that are deliberate.
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So we all know what it's like to be reflexive.
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You go through life, you're walking.
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If you already know how to walk,
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you don't think about your walking, you just walk.
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And that's because the nervous system wants to pass off
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as much as it can to reflexive action.
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That's called a bottom-up processing.
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It really just means that information is flowing in
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through your senses, regardless of what you're perceiving,
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that information is flowing up
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and it's directing your activity.
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But at any moment, for instance,
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let's say a car screeches in front of you around the corner
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and you suddenly pause,
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you are now moving into deliberate action.
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You would start looking around in a very deliberate way.
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The nervous system can be reflexive in its action
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or it can be deliberate.
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If reflexive action tends to be what we call bottom-up,
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deliberate action and deliberate perceptions
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and deliberate thoughts are top-down.
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They require some effort and some focus,
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but that's the point.
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You can decide to focus your attention and energy
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on anything you want.
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You can decide to focus your behavior in any way you want,
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but it will always feel like it requires some effort
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Whereas when you're in reflexive mode,
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just walking and talking and eating and doing your thing,
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it's gonna feel very easy.
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And that's because your nervous system basically wired up
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to be able to do most things easily
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without much metabolic demand,
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without consuming much energy.
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But the moment you try and do something very specific,
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you're gonna feel a sort of mental friction.
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It's gonna be challenging.
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So we've got sensations, perceptions,
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and then we've got things that we call feelings slash
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And these get a little complicated because almost all of us,
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I would hope all of us are familiar with things like
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happiness and sadness or boredom or frustration.
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Scientists argue like crazy,
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neuroscientists and psychologists and philosophers
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argue like crazy about what these are and how they work.
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Certainly emotions and feelings are the product
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of the nervous system.
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They involve the activity of neurons.
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But as I mentioned earlier, neurons are electrically active,
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but they also release chemicals.
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And there's a certain category of chemicals
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that has a very profound influence on our emotional states.
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They're called neuromodulators.
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And those neuromodulators have names
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that probably you've heard of before.
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Things like dopamine and serotonin and acetylcholine,
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Neuromodulators are really interesting because they bias
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which neurons are likely to be active
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and which ones are likely to be inactive.
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A simple way to think about neuromodulators is
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they are sort of like playlists that you would have
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on any kind of device where you're gonna play
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particular categories of music.
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So for instance, dopamine,
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which is often discussed as the molecule of reward or joy
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is involved in reward.
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And it does tend to create a sort of upbeat mood
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when released in appropriate amounts in the brain.
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But the reason it does that is
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because it makes certain neurons and neural circuits
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as we call them more active and others less active, okay?
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So serotonin for instance, is a molecule that when released
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tends to make us feel really good with what we have,
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our sort of internal landscape
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and the resources that we have.
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Whereas dopamine more than being a molecule of reward
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is really more a molecule of motivation
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toward things that are outside us and that we want to pursue.
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And we can look at healthy conditions or situations
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like being in pursuit of a goal
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where every time we accomplish something
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in route to that goal, a little bit of dopamine is released
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and we feel more motivation, that happens.
link |
We can also look at the extreme example
link |
of something like mania,
link |
where somebody is so relentlessly in pursuit
link |
of external things like money and relationships
link |
that they're sort of in this delusional state
link |
of thinking that they have the resources that they need
link |
in order to pursue all these things when in fact they don't.
link |
So these neuromodulators can exist in normal levels,
link |
low levels, high levels.
link |
And that actually gives us a window
link |
into a very important aspect of neuroscience history
link |
that all of us are impacted by today,
link |
which is the discovery of antidepressants
link |
and so-called antipsychotics.
link |
In the 1950s, 60s, and 70s, it was discovered
link |
that there are compounds, chemicals,
link |
that can increase or decrease serotonin,
link |
that can increase or decrease dopamine.
link |
And that led to the development
link |
of most of what we call antidepressants.
link |
Now, the trick here or the problem
link |
is that most of these drugs,
link |
especially in the 1950s and 60s,
link |
they would reduce serotonin,
link |
but they would also reduce dopamine,
link |
or they would increase serotonin,
link |
but they would also increase
link |
some other neuromodulator or chemical.
link |
And that's because all these chemical systems in the body,
link |
but the neuromodulators in particular,
link |
have a lot of receptors.
link |
Now, these are different than the receptors
link |
we were talking about earlier.
link |
The receptors I'm talking about now
link |
are sort of like parking spots where dopamine is released.
link |
And if it attaches to a receptor, say on the heart,
link |
it might make the heart beat faster
link |
because there's a certain kind of receptor on the heart.
link |
Whereas if dopamine is released
link |
and goes and attaches to muscle,
link |
it might have a completely different effect on muscle.
link |
And in fact, it does.
link |
So different receptors on different organs of the body
link |
are the ways that these neuromodulators
link |
can have all these different effects
link |
on different aspects of our biology.
link |
This is most salient in the example
link |
of some of the antidepressants
link |
that have sexual side effects,
link |
or that blunt appetite, or that blunt motivation.
link |
You know, many of these which increase serotonin
link |
can be very beneficial for people.
link |
It can elevate their mood, it can make them feel better,
link |
but they also, if the doses are too high,
link |
or if that particular drug isn't right for somebody,
link |
that person experiences challenges with motivation,
link |
or appetite, or libido,
link |
because serotonin is binding to receptors
link |
in the areas of the brain
link |
that control those other things as well.
link |
So we talked about sensation, we talked about perception.
link |
When we talk about feelings,
link |
we have to consider these neuromodulators.
link |
And we have to consider also
link |
that feelings and emotions are contextual.
link |
In some cultures, showing a lot of joy
link |
or a lot of sadness is entirely appropriate.
link |
In other cultures, it's considered inappropriate.
link |
So I don't think it's fair to say
link |
that there's a sadness circuit or area of the brain,
link |
or a happiness circuit or area of the brain.
link |
However, it is fair to say that certain chemicals
link |
and certain brain circuits tend to be active
link |
when we are in motivated states,
link |
tend to be active when we are in non-motivated, lazy states,
link |
tend to be active when we are focused,
link |
and tend to be active when we are not focused.
link |
I want to emphasize also that emotions
link |
are something that we generally feel
link |
are not under our control.
link |
We feel like the kind of guys are up within us
link |
and they just kind of happen to us.
link |
And that's because they are somewhat reflexive.
link |
We don't really set out
link |
with a deliberate thought to be happy
link |
or deliberate thought to be sad.
link |
We tend to experience them
link |
in kind of a passive reflexive way.
link |
And that brings us to the next thing, which are thoughts.
link |
Thoughts are really interesting
link |
because in many ways they're like perceptions,
link |
except that they draw on not just what's happening
link |
in the present, but also things we remember from the past
link |
and things that we anticipate about the future.
link |
The other thing about thoughts that's really interesting
link |
is that thoughts can be both reflexive,
link |
they can just be occurring all the time,
link |
sort of like pop-up windows
link |
on a poorly filtered web browser,
link |
or they can be deliberate.
link |
We can decide to have a thought.
link |
In fact, right now you could decide to have a thought
link |
just like you would decide to write something out
link |
on a piece of paper.
link |
You could decide that you're listening to a podcast,
link |
that you are in a particular location.
link |
You're not just paying attention to what's happening,
link |
you're directing your thought process.
link |
And a lot of people don't understand
link |
or at least appreciate that the thought patterns
link |
and the neural circuits that underlie thoughts
link |
can actually be controlled in this deliberate way.
link |
And then finally, there are actions.
link |
Actions or behaviors are perhaps the most important aspect
link |
to our nervous system.
link |
Because first of all, our behaviors are actually
link |
the only thing that are gonna create any fossil record
link |
After we die, the nervous system deteriorates,
link |
our skeleton will remain, but it's in the moment
link |
of experiencing something very joyful
link |
or something very sad.
link |
It can feel so all encompassing that we actually think
link |
that it has some meaning beyond that moment.
link |
But actually for humans, and I think for all species,
link |
the sensations, the perceptions and the thoughts
link |
and the feelings that we have in our lifespan,
link |
none of that is actually carried forward
link |
except the ones that we take and we convert
link |
into actions such as writing, actions such as words,
link |
actions such as engineering new things.
link |
And so the fossil record of our species
link |
and of each one of us is really through action.
link |
And that in part is why so much of our nervous system
link |
is devoted to converting sensation, perceptions,
link |
feelings, and thoughts into actions.
link |
In fact, the great neuroscientist or physiologist,
link |
Sherrington won a Nobel Prize for his work
link |
in mapping some of the circuitry,
link |
the connections between nerve cells
link |
that give rise to movement.
link |
And he said, movement is the final common pathway.
link |
The other way to think about it is that one of the reasons
link |
that our central nervous system, our brain and spinal cord
link |
include this stuff in our skull,
link |
but also connects so heavily to the body
link |
is because most everything that we experience,
link |
including our thoughts and feelings was really designed
link |
to either impact our behavior or not.
link |
And the fact that thoughts allow us to reach into the past
link |
and anticipate the future and not just experience
link |
what's happening in the moment gave rise
link |
to an incredible capacity for us to engage in behaviors
link |
that are not just for the moment.
link |
They're based on things that we know from the past
link |
and that we would like to see in the future.
link |
And this aspect to our nervous system of creating movement
link |
occurs through some very simple pathways.
link |
The reflexive pathway basically includes areas
link |
of the brainstem we call central pattern generators.
link |
When you walk, provided you already know how to walk,
link |
you are basically walking
link |
because you have these central pattern generators,
link |
groups of neurons that generate right foot, left foot,
link |
right foot, left foot kind of movement.
link |
However, when you decide to move
link |
in a particular deliberate way
link |
that requires a little more attention,
link |
you start to engage areas of your brain
link |
for top-down processing where your forebrain works
link |
from the top down to control those central pattern generators
link |
so that maybe it's right foot, right foot, left foot,
link |
right foot, right foot, left foot
link |
if maybe you're hiking along some rocks or something
link |
and you have to engage in that kind of movement.
link |
So movement is just like thoughts,
link |
can be either reflexive or deliberate.
link |
And when we talk about deliberate,
link |
I want to be very specific about how your brain works
link |
in the deliberate way because it gives rise
link |
to a very important feature of the nervous system
link |
that we're going to talk about next
link |
which is your ability to change your nervous system.
link |
And what I'd like to center on for a second is this notion
link |
of what does it mean for the nervous system
link |
to do something deliberately?
link |
Well, when you do something deliberately,
link |
you pay attention, you are bringing your perception
link |
to an analysis of three things.
link |
Duration, how long something is going to take
link |
or it should be done, path, what you should be doing,
link |
If you do something for a given length of time,
link |
what's going to happen?
link |
Now, when you're walking down the street or you're eating
link |
or you're just talking reflexively,
link |
you're not doing this what I call DPO,
link |
duration, path, outcome type of deliberate function
link |
in your brain and nervous system.
link |
But the moment you decide to learn something
link |
or to resist speaking or to speak up
link |
when you would rather be quiet,
link |
anytime you're deliberately forcing yourself
link |
over a threshold, you're engaging these brain circuits
link |
and these nervous system circuits
link |
that suddenly make it feel as if something is challenging,
link |
something has changed.
link |
Well, what's changed?
link |
What's changed is that when you engage in this duration,
link |
path and outcome type of thinking or behavior
link |
or way of being, you start to recruit these neuromodulators
link |
that are released from particular areas of your brain
link |
and also it turns out from your body,
link |
and they start queuing to your nervous system,
link |
something's different, something's different now
link |
about what I'm doing,
link |
something's different about what I'm feeling.
link |
Let's give an example where perhaps somebody says something
link |
that's triggering to you, you don't like it,
link |
and you know you shouldn't respond.
link |
You feel like, oh, I shouldn't respond,
link |
I shouldn't respond, I shouldn't respond.
link |
You're actively suppressing your behavior
link |
through top-down processing.
link |
Your forebrain is actually preventing you
link |
from saying the thing that you know you shouldn't say
link |
or that maybe you should wait to say or say
link |
in a different form.
link |
This feels like agitation and stress
link |
because you're actually suppressing a circuit.
link |
We actually can see examples of what happens
link |
when you're not doing this well.
link |
Some of the examples come from children.
link |
If you look at young children,
link |
they don't have the forebrain circuitry
link |
to engage in this top-down processing
link |
until they reach age 22, even 25.
link |
But in young children, you see this in a really robust way.
link |
You'll see they'll be rocking back and forth.
link |
It's hard for them to sit still
link |
because those central pattern generators
link |
are constantly going in the background,
link |
whereas adults can sit still.
link |
A kid sees a piece of candy that it wants
link |
and will just reach out and grab it,
link |
whereas an adult probably would ask
link |
if they could have a piece
link |
or wait until they were offered a piece in most cases.
link |
People that have damage to the certain areas
link |
of the frontal lobes don't have this kind of restriction.
link |
They'll just blurt things out.
link |
They'll just say things.
link |
We all know people like this.
link |
Impulsivity is a lack of top-down control,
link |
a lack of top-down processing.
link |
The other thing that will turn off the forebrain
link |
and make it harder to top-down processing
link |
is a couple of drinks containing alcohol.
link |
The removal of inhibition
link |
is actually a removal of neural inhibition
link |
of nerve cells suppressing the activity
link |
of other nerve cells.
link |
And so when you look at people
link |
that have damage to their frontal lobes,
link |
or you look at puppies, or you look at young children,
link |
everything's a stimulus.
link |
Everything is a potential interaction for them,
link |
and they have a very hard time
link |
restricting their behavior and their speech.
link |
So a lot of the motor system
link |
is designed to just work in a reflexive way.
link |
And then when we decide we want to learn something
link |
or do something or not do something,
link |
we have to engage in this top-down restriction,
link |
and it feels like agitation
link |
because it's accompanied by the release
link |
of a neuromodulator called norepinephrine,
link |
which in the body we call adrenaline,
link |
and it actually makes us feel agitated.
link |
So for those of you that are trying to learn something new
link |
or to learn to suppress your responses
link |
or be more deliberate and careful in your responses,
link |
that is going to feel challenging for a particular reason.
link |
It's going to feel challenging
link |
because the chemicals in your body
link |
that are released in association with that effort
link |
are designed to make you feel kind of agitated.
link |
That low-level tremor that sometimes people feel
link |
when they're really, really angry
link |
is actually a chemically induced low-level tremor.
link |
And it's the, what I call limbic friction.
link |
There's an area of your brain that's involved
link |
in our more primitive reflexive responses
link |
called the limbic system.
link |
And the frontal cortex is in a friction.
link |
It's in a tug-of-war with that system all the time,
link |
unless of course you have damage to the frontal lobe
link |
or you've had too much to drink or something,
link |
in which case you tend to just say and do whatever.
link |
And so this is really important to understand
link |
because if you want to understand neuroplasticity,
link |
you want to understand how to shape your behavior,
link |
how to shape your thinking,
link |
how to change how you're able to perform in any context,
link |
the most important thing to understand
link |
is that it requires top-down processing.
link |
It requires this feeling of agitation.
link |
In fact, I would say that agitation and strain
link |
is the entry point to neuroplasticity.
link |
So let's take a look at what neuroplasticity is.
link |
Let's explore it not as the way it's normally talked about
link |
in modern culture as a neuroplasticity.
link |
Plasticity is great.
link |
What exactly do people mean?
link |
Plasticity itself is just a process by which neurons
link |
can change their connections in the way they work
link |
so that you can go from things
link |
being very challenging and deliberate,
link |
requiring a lot of effort and strain
link |
to them being reflexive.
link |
And typically when we hear about plasticity,
link |
we're thinking about positive
link |
or what I call adaptive plasticity.
link |
A lot of plasticity can be induced,
link |
for instance, by brain damage,
link |
but that's generally not the kind of plasticity
link |
So when I say plasticity, unless I say otherwise,
link |
I mean adaptive plasticity.
link |
And in particular, most of the neuroplasticity
link |
that people want is self-directed plasticity
link |
because if there's one truism to neuroplasticity,
link |
it's that from birth until about age 25,
link |
the brain is incredibly plastic.
link |
Kids are learning all sorts of things,
link |
but they can learn it passively.
link |
They don't have to work too hard or focus too hard,
link |
although focus helps, to learn new things,
link |
acquire new languages, acquire new skills.
link |
But if you're an adult
link |
and you want to change your neural circuitry
link |
at the level of emotions or behavior or thoughts
link |
or anything really,
link |
you absolutely need to ask two important questions.
link |
One, what particular aspect of my nervous system
link |
am I trying to change?
link |
Meaning, am I trying to change my emotions
link |
or my perceptions, my sensations,
link |
and which ones are available for me to change?
link |
And then the second question is,
link |
how are you going to go about that?
link |
What is the structure of a regimen
link |
to engage neuroplasticity?
link |
And it turns out that the answer to that second question
link |
is governed by how awake or how sleepy we are.
link |
So let's talk about that next.
link |
Neuroplasticity is the ability for these connections
link |
in the brain and body to change in response to experience.
link |
And what's so incredible
link |
about the human nervous system in particular
link |
is that we can direct our own neural changes.
link |
We can decide that we want to change our brain.
link |
In other words, our brain can change itself
link |
and our nervous system can change itself.
link |
And the same can't be said for other organs of the body.
link |
Even though our other organs of the body
link |
have some ability to change, they can't direct it.
link |
They can't think and decide,
link |
oh, you know, your gut doesn't say,
link |
oh, you know, I want to be able to digest spicy foods better.
link |
So I'm going to rearrange the connections
link |
to be able to do that.
link |
Whereas your brain can decide
link |
that you want to learn a language
link |
or you want to be less emotionally reactive
link |
or more emotionally engaged.
link |
And you can undergo a series of steps
link |
that will allow your brain to make those changes
link |
so that eventually it becomes reflexive for you to do that,
link |
which is absolutely incredible.
link |
For a long time, it was thought that neuroplasticity
link |
was the unique gift of young animals and humans,
link |
that it could only occur when we're young.
link |
And in fact, the young brain is incredibly plastic.
link |
Children can learn three languages
link |
without an accent reflexively,
link |
whereas adults, it's very challenging.
link |
It takes a lot more effort and strain,
link |
a lot more of that duration path outcome kind of thinking
link |
in order to achieve those plastic changes.
link |
We now know, however, that the adult brain can change
link |
in response to experience.
link |
Nobel prizes were given for the understanding
link |
that the young brain can change very dramatically.
link |
I think one of the most extreme examples would be
link |
for people that are born blind from birth,
link |
they use the area of their brain
link |
that normally would be used for visualizing objects
link |
and colors and things outside of them for braille reading.
link |
In brain imaging studies, it's been shown that, you know,
link |
people who are blind from birth, when they braille read,
link |
the area of the brain that would normally light up,
link |
if you will, for vision, lights up for braille reading.
link |
So that real estate is reallocated
link |
for an entirely different function.
link |
If someone is made blind in adulthood,
link |
it's unlikely that their entire visual brain
link |
will be taken over by the areas of the brain
link |
they're responsible for touch.
link |
However, there's some evidence that areas of the brain
link |
that are involved in hearing and touch
link |
can kind of migrate into that area.
link |
And there's a lot of interest now in trying to figure out
link |
how more plasticity can be induced in adulthood,
link |
more positive plasticity.
link |
And in order to understand that process,
link |
we really have to understand something
link |
that might at first seem totally divorced
link |
from neuroplasticity,
link |
but actually lies at the center of neuroplasticity.
link |
And for any of you that are interested
link |
in changing your nervous system
link |
so that something that you want
link |
can go from being very hard
link |
or seem almost impossible and out of reach
link |
to being very reflexive,
link |
this is especially important to pay attention to.
link |
Plasticity in the adult human nervous system
link |
is gated, meaning it is controlled by neuromodulators.
link |
These things that we talked about earlier,
link |
dopamine, serotonin,
link |
and one in particular called acetylcholine
link |
are what open up plasticity.
link |
They literally unveil plasticity
link |
and allow brief periods of time
link |
in which whatever information,
link |
whatever thing we're sensing or perceiving or thinking,
link |
whatever emotions we feel
link |
can literally be mapped in the brain
link |
such that later it will become much easier
link |
for us to experience and feel that thing.
link |
Now this has a dark side and a positive side.
link |
The dark side is it's actually very easy
link |
to get neuroplasticity as an adult
link |
through traumatic or terrible or challenging experiences.
link |
But the important question is to say, why is that?
link |
And the reason that's the case
link |
is because when something very bad happens,
link |
there's the release of two sets of neuromodulators
link |
epinephrine, which tends to make us feel alert and agitated,
link |
which is associated with most bad circumstances,
link |
and acetylcholine, which tends to create
link |
a even more intense and focused perceptual spotlight.
link |
Remember earlier we were talking about perception
link |
and how it's kind of like a spotlight.
link |
Acetylcholine makes that light particularly bright
link |
and particularly restricted to one region of our experience.
link |
And it does that by making certain neurons in our brain
link |
and body active much more than all the rest.
link |
So acetylcholine is sort of like a highlighter marker
link |
upon which neuroplasticity then comes in later
link |
and says, wait, which neurons were active
link |
in this particularly alerting phase
link |
of whatever day or night,
link |
whenever this thing happened to happen.
link |
So the way it works is this,
link |
you can think of epinephrine as creating this alertness
link |
and this kind of unbelievable level of increased attention
link |
compared to what you were experiencing before.
link |
And you can think of acetylcholine as being the molecule
link |
that highlights whatever happens
link |
during that period of heightened alertness.
link |
So just to be clear,
link |
it's epinephrine creates the alertness
link |
that's coming from a subset of neurons in the brainstem
link |
if you're interested,
link |
and acetylcholine coming from an area of the forebrain
link |
is tagging or marking the neurons
link |
that are particularly active
link |
during this heightened level of alertness.
link |
Now that marks the cells,
link |
the neurons and the synapses for strengthening,
link |
for becoming more likely to be active in the future,
link |
even without us thinking about it, okay?
link |
So in bad circumstances,
link |
this all happens without us having to do much.
link |
When we want something to happen, however,
link |
we wanna learn a new language,
link |
we want to learn a new skill,
link |
we wanna become more motivated.
link |
What do we know for certain?
link |
We know that that process of getting neuroplasticity
link |
so that we have more focus, more motivation,
link |
absolutely requires the release of epinephrine.
link |
We have to have alertness in order to have focus,
link |
and we have to have focus
link |
in order to direct those plastic changes
link |
to particular parts of our nervous system.
link |
Now this has immense implications
link |
in thinking about the various tools,
link |
whether or not those are chemical tools or machine tools,
link |
or just self-induced regimens of how long
link |
or how intensely you're going to focus
link |
in order to get neuroplasticity.
link |
But there's another side to it.
link |
The dirty secret of neuroplasticity
link |
is that no neuroplasticity occurs
link |
during the thing you're trying to learn,
link |
during the terrible event, during the great event,
link |
during the thing that you're really trying to shape
link |
and learn nothing is actually changing
link |
between the neurons that is going to last.
link |
All the neuroplasticity, the strengthening of the synapses,
link |
the addition in some cases of new nerve cells,
link |
or at least connections between nerve cells,
link |
all of that occurs at a very different phase of life,
link |
which is when we are in sleep and non-sleep deep rest.
link |
And so neuroplasticity,
link |
which is the kind of holy grail of human experience of,
link |
you know, this is the new year
link |
and everyone's thinking new year's resolutions.
link |
And right now, perhaps everything's organized
link |
and people are highly motivated,
link |
but what happens in March or April or May?
link |
Well, that all depends on how much attention and focus
link |
one can continually bring
link |
to whatever it is they're trying to learn.
link |
So much so that agitation and a feeling of strain
link |
are actually required for this process of neuroplasticity
link |
But the actual rewiring occurs during periods of sleep
link |
and non-sleep deep rest.
link |
There's a study published last year
link |
that's particularly relevant here that I wanna share,
link |
was not done by my laboratory,
link |
that showed that 20 minutes of deep rest,
link |
this is not deep sleep,
link |
but essentially doing something very hard and very intense,
link |
and then taking 20 minutes afterwards,
link |
immediately afterwards,
link |
to deliberately turn off the deliberate focused thinking
link |
and engagement actually accelerated neuroplasticity.
link |
There's another study that's just incredible,
link |
and we're gonna go into this in a future episode
link |
of the podcast, Not Too Long From Now,
link |
that showed that if people are learning a particular skill,
link |
it could be a language skill or a motor skill,
link |
and they hear a tone just playing in the background,
link |
the tone is playing periodically through the background,
link |
like just a bell, in deep sleep, if that bell is played,
link |
learning is much faster for the thing
link |
that they were learning while they were awake.
link |
It somehow cues the nervous system in sleep,
link |
it doesn't even have to be in dreaming,
link |
that something that happened in the waking phase
link |
was especially important,
link |
so much so that that bell is sort of a Pavlovian cue,
link |
it's sort of a reminder to the sleeping brain,
link |
oh, you need to remember what it is that you were learning
link |
at that particular time of day,
link |
and the learning rates and the rates of retention,
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meaning how much people can remember
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from the thing they learned,
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are significantly higher under those conditions.
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So I'm gonna talk about how to apply all this knowledge
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in a little bit more in this podcast episode,
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but also in future episodes,
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but it really speaks to the really key importance
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of sleep and focus,
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these two opposite ends of our attentional state.
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When we're in sleep, these DPOs,
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duration, path, and outcome analysis are impossible,
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we just can't do that,
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we are only in relation to what's happening inside of us.
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also key are periods of non-sleep deep rest
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where we're turning off our analysis
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of duration, path, and outcome,
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in particular for the thing
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that we were just trying to learn,
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and we're in this kind of liminal state
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where our attention is kind of drifting all over,
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it turns out that's very important for the consolidation,
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for the changes between the nerve cells
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that will allow what we were trying to learn
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to go from being deliberate and hard and stressful
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and a strain to easy and reflexive.
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This also points to how different people,
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including many modern clinicians,
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are thinking about how to prevent bad circumstances,
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traumas from routing their way
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into our nervous system permanently.
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It says that you might wanna interfere
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with certain aspects of brain states
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that are away from the bad thing that happened,
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the brain states that happened the next day
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or the next month or the next year.
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And also I wanna make sure
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that I pay attention to the fact that for many of you,
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you're thinking about neuroplasticity,
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not just in changing your nervous system
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to add something new,
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but to also get rid of things that you don't like, right?
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That you wanna forget bad experiences
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or at least remove the emotional contingency
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of a bad relationship
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or a bad relationship to some thing or some person
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or some event, learning to fear certain things less,
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to eliminate a phobia, to erase a trauma.
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The memories themselves don't get erased.
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I'm sorry to say that the memories themselves get erased,
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but the emotional load of memories can be reduced.
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And there are a number of different ways
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that that can happen,
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but they all require this thing
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that we're calling neuroplasticity.
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We're gonna have a large number of discussions
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about neuroplasticity in depth.
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But the most important thing to understand
link |
is that it is indeed a two-phase process.
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What governs the transition between alert and focused
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and these deep rest and deep sleep states
link |
is a system in our brain and body,
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a certain aspect of the nervous system
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called the autonomic nervous system.
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And it is immensely important to understand
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how this autonomic nervous system works.
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It has names like the sympathetic nervous system
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and parasympathetic nervous system,
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which frankly are complicated names
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because they're a little bit misleading.
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Sympathetic is the one that's associated
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with more alertness.
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Parasympathetic is the one that's associated
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with more calmness.
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And it gets really misleading
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because the sympathetic nervous system sounds like sympathy
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and then people think it's related to calm.
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I'm gonna call it the alertness system
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and the calmness system,
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because even though sympathetic and parasympathetic
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are sometimes used, people really get confused.
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So the way to think about the autonomic nervous system
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and the reason it's important for every aspect of your life,
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but in particular for neuroplasticity
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and engaging in these focused states
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and then these defocused states
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is that it works sort of like a seesaw.
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Every 24 hours, we're all familiar with the fact
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that when we wake up in the morning,
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we might be a little bit groggy,
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but then generally we're more alert.
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And then as evening comes around,
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we tend to become a little more relaxed and sleepy.
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And eventually at some point at night, we go to sleep.
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So we go from alert to deeply calm.
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And as we do that, we go from an ability
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to engage in these very focused
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duration path outcome types of analysis
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to states in sleep that are completely divorced
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from duration path and outcome
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in which everything is completely random and untethered
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in terms of our sensations, perceptions
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and feelings and so forth.
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So every 24 hours, we have a phase of our day
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that is optimal for thinking and focusing
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and learning and neuroplasticity
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and doing all sorts of things.
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We have energy as well.
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And at another phase of our day, we're tired
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and we have no ability to focus.
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We have no ability to engage in duration path
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outcome types of analysis.
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And it's interesting that both phases are important
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for shaping our nervous system in the ways that we want.
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So if we want to engage in neuroplasticity
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and we want to get the most out of our nervous system,
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we each have to master that both the transition
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between wakefulness and sleep
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and the transition between sleep and wakefulness.
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Now, so much has been made of the importance of sleep.
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And it is critically important for wound healing,
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for learning, as I just mentioned,
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for consolidating learning,
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for all aspects of our immune system.
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It is the one period of time
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in which we're not doing these duration path
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and outcomes types of analyses.
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And it is critically important to all aspects of our health,
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including our longevity.
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Much less has been made, however,
link |
of how to get better at sleeping,
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how to get better at the process
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that involves falling asleep, staying asleep,
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and accessing these states of mind and body
link |
that involve total paralysis.
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Most people don't know this,
link |
but you're actually paralyzed during much of your sleep
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so that you can't act out your dreams, presumably.
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But also where your brain is in a total idle state
link |
where it's not controlling anything,
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it's just left to kind of free run.
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And there are certain things that we can all do
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in order to master that transition,
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in order to get better at sleeping.
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And it involves much more than just how much we sleep.
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We're all being told, of course,
link |
that we need to sleep more,
link |
but there's also the issue of sleep quality,
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accessing those deep states of non-DPO thinking,
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accessing the right timing of sleep.
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Not a lot has been discussed publicly,
link |
as far as I'm aware, of when to time your sleep.
link |
I think we all can appreciate that sleeping
link |
for half an hour throughout the day
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so that you get a total of eight hours of sleep
link |
every 24 hour cycle is probably very different
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and not optimal compared to a solid block
link |
of eight hours of sleep.
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Although there are people that have tried this.
link |
I think it's been written about in various books.
link |
Not many people can stick to that schedule.
link |
Incidentally, I think it's called the Uberman schedule,
link |
not to be confused with the Huberman schedule,
link |
because first of all,
link |
my schedule doesn't look anything like that.
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And second of all,
link |
I would never attempt such a sleeping regime.
link |
The other thing that is really important to understand
link |
is that we have not explored as a culture
link |
the rhythms that occur in our waking states.
link |
So much has been focused on the value of sleep
link |
and the importance of sleep, which is great,
link |
but I don't think that most people are paying attention
link |
to what's happening in their waking states
link |
and when their brain is optimized for focus,
link |
when their brain is optimized for these DPOs,
link |
these duration path outcome types of engagements
link |
for learning and for changing,
link |
and when their brain is probably better suited
link |
for more reflexive thinking and behaviors.
link |
that there's a vast amount of scientific data
link |
which points to the existence
link |
of what are called ultradian rhythms.
link |
You may have heard of circadian rhythms.
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Circadian means circa about a day.
link |
So it's 24 hour rhythms
link |
because the earth spins once every 24 hours.
link |
Ultradian rhythms occur throughout the day
link |
and they require less time, they're shorter.
link |
The most important ultradian rhythm
link |
for sake of this discussion is the 90 minute rhythm
link |
that we're going through all the time
link |
in our ability to attend and focus.
link |
And in sleep, our sleep is broken up
link |
into 90 minute segments.
link |
Early in the night,
link |
we have more phase one and phase two lighter sleep
link |
and then we go into our deeper phase three
link |
and phase four sleep
link |
and then we return to phase one, two, three, four.
link |
So all night you're going through these ultradian rhythms
link |
of stage one, two, three, four, one, two, three, four,
link |
Most people perhaps know that, maybe they don't,
link |
but when you wake up in the morning,
link |
these ultradian rhythms continue.
link |
And it turns out that we are optimized
link |
for focus and attention within these 90 minute cycles
link |
so that at the beginning of one of these 90 minute cycles,
link |
maybe you sit down to learn something new
link |
or to engage in some new challenging behavior.
link |
For the first five or 10 minutes of one of those cycles,
link |
it's well known that the brain and the neural circuits
link |
and the neuromodulators are not gonna be optimally tuned
link |
to whatever it is you're trying to do.
link |
But as you drop deeper into that 90 minute cycle,
link |
your ability to focus and to engage in this DPO process
link |
and to direct neural plasticity and to learn
link |
is actually much greater.
link |
And then you eventually pop out of that
link |
at the end of the 90 minute cycle.
link |
So these cycles are occurring in sleep
link |
and these cycles are occurring in wakefulness.
link |
And all of those are governed by this seesaw
link |
of alertness to calmness
link |
that we call the autonomic nervous system.
link |
So if you want to master and control your nervous system,
link |
regardless of what tool you reach to,
link |
whether or not it's a pharmacologic tool
link |
or whether or not it's a behavioral tool
link |
or whether or not it's a brain machine interface tool,
link |
it's vitally important to understand
link |
that your entire existence
link |
is occurring in these 90 minute cycles,
link |
whether or not you're asleep or awake.
link |
And so you really need to learn
link |
how to wedge into those 90 minute cycles.
link |
And for instance, it would be completely crazy
link |
and counterproductive to try and just learn information
link |
while in deep sleep by listening to that information
link |
because you're not able to access it.
link |
It would be perfectly good, however,
link |
to engage in a focus bout of learning each day.
link |
And now we know how long
link |
that focus bout of learning should be.
link |
It should be at least one 90 minute cycle.
link |
And the expectation should be that the early phase
link |
of that cycle is going to be challenging.
link |
It's going to hurt.
link |
It's not going to feel natural.
link |
It's not going to feel like flow,
link |
but that you can learn
link |
and the circuits of your brain
link |
that are involved in focus and motivation
link |
can learn to drop in to a mode of more focus,
link |
get more neuroplasticity, in other words,
link |
by engaging these ultradian cycles
link |
at the appropriate times of day.
link |
For instance, some people are very good learners
link |
early in the day and not so good in the afternoon.
link |
So you can start to explore this process
link |
even without any information
link |
about the underlying neurochemicals
link |
by simply paying attention,
link |
not just to when you go to sleep
link |
and when you wake up each morning,
link |
how deep or how shallow your sleep felt to you subjectively,
link |
but also throughout the day
link |
when your brain tends to be most anxious,
link |
because it turns out that has a correlate
link |
related to perception that we will talk about.
link |
You can ask yourself, when are you most focused?
link |
When are you least anxious?
link |
When do you feel most motivated?
link |
When do you feel least motivated?
link |
By understanding how the different aspects
link |
of your perception, sensation, feeling, thought,
link |
and actions tend to want to be engaged
link |
or not want to be engaged,
link |
you develop a very good window
link |
into what's going to be required
link |
to shift your ability to focus
link |
or shift your ability to engage in creative type thinking
link |
at different times of day, should you choose.
link |
And so that's where we're heading going forward.
link |
It all starts with mastering this seesaw
link |
that is the autonomic nervous system
link |
that at a course level is a transition
link |
between wakefulness and sleep.
link |
But at a finer level, and just as important
link |
are the various cycles,
link |
these ultradian 90 minute cycles
link |
that govern our life all the time,
link |
24 hours a day, every day of our life.
link |
And so we're going to talk about
link |
how you can take control of the autonomic nervous system
link |
so that you can better access neuroplasticity,
link |
better access sleep,
link |
even take advantage of the phase
link |
that is the transition between sleep and waking
link |
to access things like creativity and so forth.
link |
All based on studies that have been published
link |
over the last hundred years,
link |
mainly within the last 10 years
link |
and some that are very, very new
link |
and that point to the use of specific tools
link |
that will allow you to get the most
link |
out of your nervous system.
link |
So today we covered a lot of information.
link |
It was sort of a whirlwind tour
link |
of everything from neurons and synapses
link |
to neuroplasticity in the autonomic nervous system.
link |
We will revisit a lot of these themes going forward.
link |
So if all of that didn't sink in in one pass,
link |
please don't worry.
link |
We will come back to these themes over and over again.
link |
I wanted to equip you with a language
link |
that we're all developing a kind of common base set
link |
of information going forward.
link |
And I hope the information is valuable to you
link |
in your thinking about what is working well for you
link |
and what's working less well
link |
and what's been exceedingly challenging
link |
and what's been easy for you
link |
in terms of your pursuit of particular behaviors
link |
or emotional states,
link |
where your challenges or the challenges of people
link |
that you know might reside.
link |
As promised in our welcome video,
link |
the format of the Huberman Lab Podcast
link |
is to dive deep into individual topics
link |
for an entire month at a time.
link |
So for the entire month of January,
link |
we're going to explore this incredible state that is sleep
link |
and a related state, which is non-sleep deep rest.
link |
And what they do for things like learning,
link |
resetting our emotional capacity.
link |
Everyone's probably familiar with the fact
link |
that when we're sleep deprived,
link |
we're so much less good at dealing with life circumstances.
link |
We're more emotionally labile.
link |
But most importantly,
link |
we're going to talk about how to get better at sleeping
link |
and then how to access better sleep,
link |
even when your sleep timing or duration is compromised.
link |
We're also going to talk about the data
link |
that support this very interesting state
link |
called non-sleep deep rest,
link |
where one is neither asleep nor awake,
link |
but it turns out one can recover
link |
some of the neuromodulators
link |
and more importantly,
link |
the processes involved in sensation, perception,
link |
feeling, thought, and action.
link |
It's sure to be a very rich discussion back and forth
link |
where I'm answering your questions and providing tools.
link |
And I'm certain you're also going to learn
link |
a lot of information about neuroscience
link |
and what makes up this incredible phase of your life
link |
where you think you're not conscious,
link |
but you're actually resetting and renewing yourself
link |
in order to perform better, feel better, et cetera,
link |
in the waking state.
link |
If you want to support the podcast,
link |
please click the like button and subscribe on YouTube.
link |
Leave us a comment if you have any feedback for us.
link |
And on Apple, you can also leave a review
link |
and comments for us to improve
link |
the podcast experience for you.
link |
Please also check out our sponsors and thank you so much.
link |
We'll see you on the next episode next week.
link |
We'll see you on the next episode.