Speaker 1: When you make a choice, who exactly is doing the choosing?
Speaker 1: Is there someone in your head but it's not you?
Speaker 1: What is a chicken sexer? And what do they have
Speaker 1: to do with British plane spotters during World War Two?
Speaker 1: Do we have free will or don't we? Welcome to
Speaker 1: enter cosmos with me, David Eagleman, I'm a neuroscientist at
Speaker 1: Stanford and one of my big interests has always been
Speaker 1: understanding all the stuff we do that we don't have
Speaker 1: access to why we did it, or the stuff we
Speaker 1: believe is true, but we don't have access to why
Speaker 1: we believe it. So this is going to be a
Speaker 1: two parter. In today's episode, I'm going to dive into
Speaker 1: all the things that your brain is doing around the
Speaker 1: clock that the conscious you has no insight into and
Speaker 1: really no acquaintance with all this activity that lives within
Speaker 1: what we call the unconscious brain. You're only conscious of
Speaker 1: a tiny bit of what's happening under the hood. So
Speaker 1: today we're going to see how all this unconscious activity
Speaker 1: drives so much more of your life than you would
Speaker 1: have imagined. And then in the next episode, I'll talk
Speaker 1: about what all this means for our legal system. If
Speaker 1: your behavior and your choices are driven by parts of
Speaker 1: your brain that you have little or no control over,
Speaker 1: what does that mean if you commit a crime, can
Speaker 1: you help that you did it? Did you have a
Speaker 1: choice or does your brain get formed by your genetics
Speaker 1: and your childhood experience, neither of which you had any
Speaker 1: choice over? So what does that all mean for the
Speaker 1: notion of fault and blame worthiness in our legal system?
Speaker 1: What would that mean for our courts? Because you can't
Speaker 1: just let everyone off the hook, even if they didn't
Speaker 1: have a choice and who they are right. So next
Speaker 1: week we'll dive into what happens at the intersection of
Speaker 1: neuroscience and the legal system and how we can build
Speaker 1: a system moving forward that gets bad actors off the
Speaker 1: street and is compatible with insights of modern neuroscience. So
Speaker 1: let's start at the beginning. Ours is an incredible story.
Speaker 1: As far as anyone can tell. We are the only
Speaker 1: species on the planet that has grown so complex that
Speaker 1: we have thrown ourselves headlong into this game of reverse
Speaker 1: engineering ourselves. Imagine that you plugged some peripheral devices into
Speaker 1: your laptop and it began to control those and removed
Speaker 1: its own cover and pointed its webcam at its own
Speaker 1: circuitry and tried to figure out how it runs. That's us,
Speaker 1: that's our species. And what we have discovered by peering
Speaker 1: into the skull ranks some among our most significant intellectual developments.
Speaker 1: What we found is that all the facets of our behavior,
Speaker 1: our thoughts, our experiences, these are inseparably yoked to this vast,
Speaker 1: wet chemical electrical network called the nervous system. And this
Speaker 1: machinery is totally alien to us, and yet somehow it
Speaker 1: is us. When we look at the brain, this is
Speaker 1: the most complex device we have ever found in our universe.
Speaker 1: The human brain is made up of eighty six billion
Speaker 1: specialized cells called neurons, and each neuron is as complicated
Speaker 1: as the city of New York. Every neuron contains the
Speaker 1: entire human genome, and it's trafficking millions of proteins around
Speaker 1: inside it. And every neuron is connected to about ten
Speaker 1: thousand of its neighbors. So that means you have something
Speaker 1: like five hundred trillion connections in your brain. So that
Speaker 1: means if you took a cubic centimeter of your brain
Speaker 1: and you examined that there are as many connections in
Speaker 1: there as there are stars in the Milky Way galaxy.
Speaker 1: It's totally impossible for any of us to understand a
Speaker 1: system of this complexity. But one thing is clear. This
Speaker 1: three pounds of wet biological stuff is you. All your thoughts,
Speaker 1: your hopes, your fears, the agony and the ecstasy. It's
Speaker 1: all happening right inside here in your brain, in the
Speaker 1: darkness of your skull. So, in other words, it's not
Speaker 1: that you have a brain, it's that you are your brain.
Speaker 1: So how do we know this, Well, imagine you were
Speaker 1: to get in a car accident and you hurt the
Speaker 1: tip of your pinky. You'd be sad about that, but
Speaker 1: you wouldn't be any different as a person. But if
Speaker 1: you were to damage an equivalently sized little chunk of
Speaker 1: brain tissue, that can change you entirely. That can change
Speaker 1: your decision making or your appetite for risk, or your
Speaker 1: ability to see colors or name animals, or understand music,
Speaker 1: or read signals from your body, or to understand the
Speaker 1: concept of a mirror, or one hundred other things that
Speaker 1: we see every day in the clinics when people get
Speaker 1: brain damage due to strokes or tumors or traumatic brain injury.
Speaker 1: Now here's the surprise. Almost all of this machinery of
Speaker 1: you runs under the hood, meaning you don't even have
Speaker 1: access to it or have any acquaintance with it. So
Speaker 1: think about moving your arm to get your coffee mug
Speaker 1: to your mouth. That feels very simple, but it's actually
Speaker 1: underpinned by a lightning storm of brain activity. Literally, hundreds
Speaker 1: of millions of neurons are popping off the chattering with
Speaker 1: these electrical spikes between tens or hundreds of times per
Speaker 1: second to allow you to grip the cup see the
Speaker 1: cup arranger. Grip on the handle, lift it with the
Speaker 1: right strength, bring it to your mouth, position it against
Speaker 1: your lower lip tilted, take a sip. Okay. The remarkable
Speaker 1: thing is you don't have any awareness of all these
Speaker 1: microscopic neurons and their massive dialogue that they're chattering away in.
Speaker 1: And by massive, I mean every neuron in your head
Speaker 1: is shooting off these little electrical spikes tens or hundreds
Speaker 1: of times per second every second of your life. And
Speaker 1: multiply that times these eighty six billion neurons. If you
Speaker 1: represented each spike by a single photon of light, the
Speaker 1: action inside your skull at any moment would be blinding.
Speaker 1: But the thing I want to zoom into today is
Speaker 1: that you don't have any awareness of this, any insight
Speaker 1: or consciousness of all the action going on. The only
Speaker 1: thing you know is whether you spilled the coffee on
Speaker 1: yourself or not. That's it. All the action is happening
Speaker 1: at the level of billions of biological cells, and you
Speaker 1: don't even know how you do it. Now, it's not
Speaker 1: just your cup of coffee. It's everything in your life.
Speaker 1: It's how you drive a car, it's how you recognize
Speaker 1: a friend's face, it's how you get a joke, it's
Speaker 1: how you fall in love. These are all underpinned by
Speaker 1: massive storms of electrochemical activity inside the darkness of your skull.
Speaker 1: So the conscious you is really the smallest part of
Speaker 1: what your brain is up to. Here's an example that
Speaker 1: got me thinking about this. When I was young. There
Speaker 1: was an old experiment at the University of Chicago. And
Speaker 1: in this experiment, men were asked to rate how attractive
Speaker 1: they found photographs of different women's faces. So the photographs
Speaker 1: were eight by ten photos and they would flip through
Speaker 1: them and they would rank each women from one to ten. Now,
Speaker 1: unbeknown to the men, in half the photographs, the eyes
Speaker 1: were dilated, and in the other half of the photographs
Speaker 1: the eyes were normal. So the result turned out to
Speaker 1: me that the men were consistently more attracted to the
Speaker 1: women with dilated eyes. But the important point is that
Speaker 1: the men had no insight into their decision making. None
Speaker 1: of them said, oh, I noticed that her pupils were
Speaker 1: two millimeters larger than her pupils, And presumably none of
Speaker 1: the men knew that dilated eyes is a biological sign
Speaker 1: of reciprocal attraction. But their brains knew it, and here
Speaker 1: they were making the right sorts of decisions, as carved
Speaker 1: by millions of years of natural selection, without having any
Speaker 1: idea why they were making those decisions. They simply felt
Speaker 1: more drawn towards some women than others for reasons they
Speaker 1: couldn't put finger on. So who was doing the choosing.
Speaker 1: It wasn't really like the men were choosing, but instead
Speaker 1: it was a choice of successful neural programs that had
Speaker 1: been burned deep into the circuitry over the course of
Speaker 1: hundreds of thousands of generations. Brains are in the business
Speaker 1: of gathering information and steering behavior appropriately, and it doesn't
Speaker 1: matter whether consciousness is involved in the decision making, and
Speaker 1: most of the time it's not. This is true whether
Speaker 1: we're talking about dilated eyes, or the sting of jealousy,
Speaker 1: or the pull of attraction, or your love of sugary
Speaker 1: cookies or the great idea that popped into your head
Speaker 1: last week. For all of these, consciousness is the smallest
Speaker 1: player in the operations of your brain. Your brain runs
Speaker 1: mostly on autopilot, and your conscious mind has very little
Speaker 1: access to the giant and mista furious factory that runs
Speaker 1: below it. And when you start looking around, you see
Speaker 1: evidence of this all around you. So think of when
Speaker 1: your foot gets halfway to the break of your car
Speaker 1: before you consciously realize that a truck is backing out
Speaker 1: of a driveway on the road ahead of you, or
Speaker 1: when you notice your name spoken in a conversation across
Speaker 1: the room that you thought you weren't listening to. You
Speaker 1: see this when you're in a conversation and you don't
Speaker 1: know the words that are going to spill out of
Speaker 1: your mouth, You the conscious you just sits in the
Speaker 1: back seat and waits to see what comes pouring out. Now,
Speaker 1: the brain is massively complex, but that doesn't mean that
Speaker 1: it's incomprehensible. Our neural circuits were carved by natural selection
Speaker 1: to solve problems that our ancestors faced during our species
Speaker 1: evolutionary history. So your brain has been molded by evolutionary pressures,
Speaker 1: just like your spleen and your eyes have, and so
Speaker 1: has your consciousness. Consciousness developed because it was advantageous, but
Speaker 1: only advantageous in limited amounts. So why do we have
Speaker 1: consciousness at all? Well, think of this as an analogy.
Speaker 1: Look at all the activity that's happening in the nation
Speaker 1: at any moment. You've got factories going and telecommunication lines
Speaker 1: and businesses shipping product and people eating, and police chasing
Speaker 1: criminals and schools running and lovers rendezvousing, and everyone's doing
Speaker 1: their thing, teachers and athletes and doctors. There's a ton
Speaker 1: of action going on in the nation. Now, you want
Speaker 1: to know what's happening in the nation, but you can't
Speaker 1: possibly take in all this information at once. It's too
Speaker 1: much to be useful even if you could take it in.
Speaker 1: So what you want is a summary. So you go
Speaker 1: to a news website and you won't be surprised that
Speaker 1: none of the details are listed there, because really you
Speaker 1: just want to know the bottom line. You want to
Speaker 1: know that Congress just signed a law that affects you,
Speaker 1: But you don't have interest in the detailed history of
Speaker 1: the bill, and you don't want to know all the
Speaker 1: details of the food supply of the nation. You only
Speaker 1: want to be alerted if there's something that affects you.
Speaker 1: You don't care how the garbage is produced and packed away.
Speaker 1: You only care if it's going to end up in
Speaker 1: your backyard. That's what you get from reading the news headlines.
Speaker 1: Your conscious mind gives you the headlines. Your brain is
Speaker 1: buzzing with activity around the clock, and just like the nation,
Speaker 1: everything is happening locally. You've got groups of neurons that
Speaker 1: are making decisions and sending out messages to other groups.
Speaker 1: And out of these local interactions emerge larger coalitions. And
Speaker 1: by the time you read a mental headline, all the
Speaker 1: important action has already transpired, all the deals are done.
Speaker 1: You have shockingly little access to what happened behind the
Speaker 1: scenes to lead you up to this moment. Entire political
Speaker 1: movements have gained ground up support and become unstoppable before
Speaker 1: you ever catch wind of them as a feeling or
Speaker 1: an intuition or a thought. That strikes you. You're the
Speaker 1: last one to hear the information. But strangely, you're an
Speaker 1: odd kind of newsreader because you read the headline and
Speaker 1: you take credit for the idea as though you thought
Speaker 1: of it first. Just think about when you have an
Speaker 1: idea and you say, oh, I just thought of something.
Speaker 1: It wasn't exactly you that thought of it. Your brain's
Speaker 1: been working on that behind the scenes for hours or
Speaker 1: days or weeks, consolidating information, evaluating options, and eventually it
Speaker 1: serves something up to your conscious mind and you say, oh,
Speaker 1: I'm a genius, but it wasn't really you. Right, you're
Speaker 1: taking credit without considering the vast hidden machinery behind the scenes.
Speaker 1: So the conscious you, which is the part that flickers
Speaker 1: to life when you wake up in the morning, that's
Speaker 1: the smallest bit of what's going on in your brain.
Speaker 1: It's a broom closet in the mansion of the brain.
Speaker 1: Most of what you think and do and believe is
Speaker 1: generated by functions of your brain to which you have
Speaker 1: no access. So the conscious mind is like a stowaway
Speaker 1: on a transatlantic steamship that's taking credit for the whole
Speaker 1: journey without acknowledging all the massive engineering that's underfoot, and
Speaker 1: it kind of has to be that way because really
Speaker 1: the conscious mind is acting like the CEO of an
Speaker 1: enormous organization. So think if you're the CEO of some
Speaker 1: huge international company, you can't possibly get involved with all
Speaker 1: the little tasks of knowing what software version is on employees' computers,
Speaker 1: or where the food for the cafeteria is coming from,
Speaker 1: or where the truck tires are being ordered from. The
Speaker 1: organization is just way too big. So your job as
Speaker 1: the CEO is to kick your feet up on the
Speaker 1: desk and wait for the phond erring if there's a problem.
Speaker 1: And this is essentially what the conscious mind is doing.
Speaker 1: So who exactly deserves the credit for the great idea
Speaker 1: that you have? This is a tough one that people
Speaker 1: have been wrestling with for ages. I was recently reading
Speaker 1: about the mathematician James Clerk Maxwell, who in eighteen sixty
Speaker 1: two developed a set of Sweet equations to unify electricity
Speaker 1: with magnetism. But on his deathbed he said that quote
Speaker 1: something within him unquote discovered the famous equations, not him.
Speaker 1: He had admitted that he had no idea how ideas
Speaker 1: actually came to him. They simply came to him. The
Speaker 1: author William Blake wrote the long poem Milton, and later
Speaker 1: he said, quote, I have written this poem from immediate dictation,
Speaker 1: twelve or sometimes twenty lines at a time, without premeditation,
Speaker 1: and even against my will unquote. Or the novelist Kurtis
Speaker 1: said that he had written one of his novellas with
Speaker 1: practically no conscious input, as though he were holding a
Speaker 1: pen that moved on its own. Or think about the
Speaker 1: British poet Samuel Taylor Coleridge. He started to use opium
Speaker 1: in seventeen ninety six, and originally it was for relief
Speaker 1: from toothaches, but after a while he was addicted and
Speaker 1: he wrote his famous poem Kubla Khan on an opium high.
Speaker 1: Now we give credit for that poem to Coleridge because
Speaker 1: it came from his brain and no one else's right,
Speaker 1: But he couldn't get hold of those words while so, so,
Speaker 1: who exactly does credit for the poem belong to? As
Speaker 1: Carl Jung said, in each of us there is another
Speaker 1: whom we do not know, Or as Pink Floyd put it,
Speaker 1: there's someone in my head, but it's not me. Almost
Speaker 1: everything in your mental life is not under your conscious control.
Speaker 1: And the truth is it's better that way. Consciousness can
Speaker 1: take all the credit it wants, but it's best left
Speaker 1: at the sidelines for most of the decision making that
Speaker 1: cranks along in your brain. When your conscious mind messes
Speaker 1: with details that it doesn't understand, the whole operation runs
Speaker 1: less effectively. So if you play the piano, you know
Speaker 1: that if you start to think about where your fingers
Speaker 1: are going, you're dead. You can't do it anymore. Or
Speaker 1: here's something to try. I want you to try this.
Speaker 1: Take two dry erase markers and go stand in front
Speaker 1: of the dry erase port. And what I want you
Speaker 1: to do is write your signature with your right hand
Speaker 1: at the same time that you're writing it backwards with
Speaker 1: your left hand. So you're writing your signature and its
Speaker 1: mirror reverse at the same time. So go ahead, try
Speaker 1: this for a moment if you are near a dry
Speaker 1: erase board, and you'll quickly find that there's only one
Speaker 1: way you can do it, and that is if you
Speaker 1: don't think about it at all. The moment you start
Speaker 1: thinking about what a backwards letter looks like, the whole
Speaker 1: thing fails. You stumble, and you stutter along and you
Speaker 1: just can't do it. But you actually can't do this
Speaker 1: if you simply don't think about it, if you just
Speaker 1: zen out and let your hands do the work. So
Speaker 1: you can only do it if you exclude conscious thought.
Speaker 1: Here's another example. Pretend you're driving, and what I want
Speaker 1: you to do is actually put your hands up on
Speaker 1: an imaginary steering wheel in front of you. So put
Speaker 1: your hands there, and if you're in a car while
Speaker 1: listening to this podcast, don't do this, okay. So imagine
Speaker 1: with your hands on the imaginary steering wheel that you
Speaker 1: are in the center lane going thirty miles an hour,
Speaker 1: and I want you to make a lane change into
Speaker 1: your right lane. So go ahead and turn the wheel
Speaker 1: in the way that you would to make a lane change. Now,
Speaker 1: if you're like essentially everybody who I've ever tried this with,
Speaker 1: what you do is you turn your wheel to the
Speaker 1: right and then back to center. Is that what you did, Okay?
Speaker 1: So that turns your car to the right, and now
Speaker 1: you bump over the sidewalk and you crash into the buildings.
Speaker 1: The way you make a lane change is by turning
Speaker 1: the steering wheel to the right, then back through the center,
Speaker 1: and just as far to the left and then you're
Speaker 1: back to the center again. So if you're in a car,
Speaker 1: pay attention to how you're doing this, and you'll see
Speaker 1: that's how you make a lane change, and you do
Speaker 1: it every day and you have no idea how you're
Speaker 1: doing it. Why. It's because your unconscious brain is taking
Speaker 1: care of all the details for you and you don't
Speaker 1: even have access to what you're doing. So you can
Speaker 1: do lots of things well with no consciousness involved. When
Speaker 1: I was younger, I used to play baseball and my
Speaker 1: coach would always say to us, I want you guys
Speaker 1: to think out there. And I would say to him, actually,
Speaker 1: you don't want us to think out there. You want
Speaker 1: us to train a sufficient number of hours so that
Speaker 1: we automatize all these behaviors and then we go out
Speaker 1: there and perform. But the last thing you want us
Speaker 1: doing out there is thinking, because we would never connect
Speaker 1: the bat with the ball or catch the pop fly.
Speaker 1: But he never believed me, so I had to go
Speaker 1: become a neuroscientist and write books to convince him that
Speaker 1: consciousness typically doesn't even get invited to the party. And
Speaker 1: by the way, when consciousness does get any insight, it's
Speaker 1: always the last one to hear the information. So think
Speaker 1: about hitting a baseball. In twenty ten, the Guinness Book
Speaker 1: of World Records clocked a fastball from the Cincinnati pitcher
Speaker 1: or all this Chapman, at one hundred and five point
Speaker 1: eight miles per hour. So if you work the numbers,
Speaker 1: what you see is that Chapman's pitch left the mound
Speaker 1: and cross the home plate in four tenths of a second,
Speaker 1: four hundred milliseconds. What that means is there's just enough
Speaker 1: time for light signals from the baseball to reach the
Speaker 1: batter's eye work through the circuitry of the retina. Activate
Speaker 1: these successions of cells along the loopy super highways of
Speaker 1: the visual system at the back of the head, cross
Speaker 1: the vast territories to the motor areas, and modify the
Speaker 1: contraction of the muscles swinging the bat. And amazingly, this
Speaker 1: entire sequence is possible in less than four tenths of
Speaker 1: a second. Otherwise no one would ever hit a fastball.
Speaker 1: But the surprising part is that conscious awareness takes longer
Speaker 1: than that, at least half a second, so the ball
Speaker 1: travels too rapidly for batters to be consciously aware of it.
Speaker 1: And when I was playing baseball, my experience of hitting
Speaker 1: the ball was always this. I would stand there ready
Speaker 1: to swing, and then I would become consciously aware that
Speaker 1: I had hit the ball and it was flying away
Speaker 1: from me, and then I would say to myself, you
Speaker 1: hit the ball, Now drop the bat and run. But
Speaker 1: the actual moment of hitting the ball with the bat
Speaker 1: was always moving way ahead of my slow consciousness, which
Speaker 1: was the last one on the ladder to get any
Speaker 1: of the news of what was transpiring. And all. This
Speaker 1: is the case because you don't need to be consciously
Speaker 1: aware to perform sophisticated motor acts. You can notice this
Speaker 1: when you begin to duck from a snapping tree branch
Speaker 1: before you are aware that is coming towards you, or
Speaker 1: you're already jumping up by the time you realize that
Speaker 1: your cell phone is ringing across the room. So these
Speaker 1: examples about writing your signature backward, or changing lanes, or
Speaker 1: hitting a baseball, these are a few among thousands. You
Speaker 1: are not consciously aware of the vast majority of your
Speaker 1: brain's ongoing activities, and nor would you want to be.
Speaker 1: It would interfere with the brain's well oiled processes. The
Speaker 1: best way to mess up your piano piece is to
Speaker 1: concentrate on your fingers. The best way to get out
Speaker 1: of breath is to think about your breathing. The best
Speaker 1: way to miss your golf ball is to think too
Speaker 1: much about your swing. And by the way, this wisdom
Speaker 1: is apparent even to children. We find it immortalized in
Speaker 1: poems like the Puzzled Centipede, which goes like this. A
Speaker 1: centipede was happy quite until a frog in fun said,
Speaker 1: pray tell which leg comes? After which this raised her
Speaker 1: mind to such a pitch she lay distracted in the ditch,
Speaker 1: not knowing how to run. So this ability to remember
Speaker 1: how to do motor acts like changing lanes is called
Speaker 1: procedural memory, and it's a type of implicit memory. Implicit
Speaker 1: means that your brain holds the knowledge of something that
Speaker 1: your conscious mind can't access, like riding a bike, or
Speaker 1: tying your shoes, or typing on a keyboard, or steering
Speaker 1: your car into a parking space while you're talking on
Speaker 1: your cell phone. These are all examples of implicit memory.
Speaker 1: You can execute these actions easily enough without having any
Speaker 1: idea of exactly how you do it. You would be
Speaker 1: totally unable to describe the perfectly timed choreography with which
Speaker 1: your muscles contract and relax as you do these things,
Speaker 1: or as you navigate around other people in a cafeteria
Speaker 1: while you're holding a tray. But you don't have any
Speaker 1: trouble doing any of these things. This is the gap
Speaker 1: between what your unconscious brain can do and what you
Speaker 1: can access consciously. To the extent that consciousness is useful,
Speaker 1: it's useful in small quantities and for very particular kinds
Speaker 1: of tasks. It's easy enough to understand why you wouldn't
Speaker 1: want to be consciously aware of the intricacies of your
Speaker 1: muscle movement, but this can be a little less intuitive
Speaker 1: when applied to your perceptions and thoughts and beliefs, which
Speaker 1: are also the final products of the activity of billions
Speaker 1: of nerve cells. For a good example of this, can
Speaker 1: consider chicken sexers. So what is a chicken sexer? Well,
Speaker 1: when little chicken hatchlings are born, large commercial hatcheries divide
Speaker 1: them up into males and females, and this practice of
Speaker 1: figuring out which is which, of distinguishing the two genders,
Speaker 1: this is known as chicken sexing. Now the hatcheries divide
Speaker 1: them up because the two genders get different feeding programs.
Speaker 1: The females who will eventually lay eggs are highly valued,
Speaker 1: but sadly, most of the males are disposed of because
Speaker 1: they don't produce eggs, and only a few males are
Speaker 1: kept in fatten for meat. So anyway, the job of
Speaker 1: the chicken sexor is to pick up each hatchling and
Speaker 1: quickly determine its sex in order to choose the correct
Speaker 1: bin to put it in. The problem is that this
Speaker 1: task is famously difficult because female and male chicks look
Speaker 1: exactly alike, well almost exactly. So the Japanese invented a
Speaker 1: method of sexing chicks known as vent sexing, by which
Speaker 1: expert chicken sexers could rapidly figure out the sex of
Speaker 1: one day old hatchlings. So, beginning in the nineteen thirties,
Speaker 1: poultry breeders from around the world traveled to the zen
Speaker 1: Nippon Chick Sexing School in Japan to learn the technique.
Speaker 1: The mystery was that no one could explain exactly how
Speaker 1: it was done. It was somehow based on very subtle
Speaker 1: visual cues, but the professional chick sexors could not report
Speaker 1: what those cues were. Instead, they would look at the
Speaker 1: chicks rear end where the vent is and simply seem
Speaker 1: to know the correct bin to put it in. And
Speaker 1: this is how the professionals taught the students. The master
Speaker 1: would stand over the apprentice and watch the student would
Speaker 1: pick up a chick, examine its rear, and put it
Speaker 1: in one bin or the other, and the master would
Speaker 1: give feedback yes or no. And after weeks on end
Speaker 1: of this activity, the student's brain was trained up to
Speaker 1: masterful levels that were totally unconscious. They could tell the
Speaker 1: sects of the chicken, but they had no idea how
Speaker 1: they were doing it. Meanwhile, a similar story was unfolding
Speaker 1: on the other side of the world during World War Two.
Speaker 1: Under a constant threat of bombings, the British had to
Speaker 1: figure out how to distinguish incoming aircraft quickly and accurately.
Speaker 1: Which aircraft were British planes coming home and which were
Speaker 1: German planes coming to bomb. So, as it turns out,
Speaker 1: there were several airplane enthusiasts who proved to be excellent spotters,
Speaker 1: so the military eagerly employed their services. These spotters were
Speaker 1: so valuable that the government quickly tried to enlist more spotters,
Speaker 1: but they turned out to be very rare and difficult
Speaker 1: to find. So what did the government do. They tried
Speaker 1: to get the spotters to sit down and train other spotters,
Speaker 1: but that turned out to be a total fail because
Speaker 1: the spotters tried to explain their strategies but failed. No
Speaker 1: one got it, not even the spotters themselves. Just like
Speaker 1: the chicken sextors, the spotters had no idea how they
Speaker 1: did what they did. They simply saw the right answer.
Speaker 1: But with a little ingenuity, the British finally figured out
Speaker 1: how to successfully train new spotters, and it was just
Speaker 1: by trial and error feedback. So the novice would hazard
Speaker 1: a guess and say I think that's a British plane
Speaker 1: or I think that's a German plane, and the expert
Speaker 1: would say yes or no, and eventually the novices became
Speaker 1: like their mentors, vessels of this mysterious, ineffable expertise. So
Speaker 1: there can be a really large gap between knowledge that
Speaker 1: your brain has and your conscious awareness. So when we
Speaker 1: examine skills that aren't available to introspection, like making a
Speaker 1: lane change, or hitting the baseball or chicken sexing, the
Speaker 1: first surprise is that your brain's unconscious memory for something
Speaker 1: your implicit memory is totally separable from things that you
Speaker 1: can talk about consciously or your explicit memory. You can
Speaker 1: damage one without hurting the other. So, for example, sometimes
Speaker 1: a person will get brain damage and get what's called
Speaker 1: antaro grade amnesia, which means they can't consciously recall new
Speaker 1: experiences in their lives. If you spend an afternoon trying
Speaker 1: to teach a person like this the video game Tetris,
Speaker 1: they'll tell you the next day that they have no
Speaker 1: recollection of the experience. They've never seen this deo game before,
Speaker 1: and most likely they don't have any idea who you
Speaker 1: are either. But if you look at their performance on
Speaker 1: the game the next day, you'll find that they have
Speaker 1: improved exactly as much as a person without amnesia. In
Speaker 1: other words, their brains have learned the game implicitly. The
Speaker 1: knowledge is there, it's just that it's not accessible to
Speaker 1: their consciousness. By the way, it's an interesting side note.
Speaker 1: If you wake up an amnestic patient during the night
Speaker 1: after they've played Tetris, they'll report to you that they
Speaker 1: were dreaming of colorful falling blocks, but they have no
Speaker 1: idea why. And of course it's not just checking sexors
Speaker 1: and plane spotters and people with amnesia who enjoy unconscious learning. Essentially,
Speaker 1: everything about your interaction with the world rests on this process.
Speaker 1: You probably would have a difficult time putting into words
Speaker 1: the characteristics of your father's walk, or the shape of
Speaker 1: his nose, or the way that he laughs. When you
Speaker 1: see someone who walks or looks or laughs like him,
Speaker 1: you know it immediately. Now, I want to return to
Speaker 1: this point that I mentioned at the beginning, which is
Speaker 1: that you are your brain and this is why things
Speaker 1: like brain damage can change you. But you don't need
Speaker 1: brain damage to prove this to yourself. Just look at
Speaker 1: the ways that you change when your biology changes. So
Speaker 1: consider alcohol. You pour these invisibly small ethanol molecules into
Speaker 1: your system, and that alters your perception and your behavior.
Speaker 1: Your social inhibitions are lower, you feel freer, you think
Speaker 1: your funnier at parties, you do more adventurous things. It's
Speaker 1: just a molecule of a particular shape that interacts with
Speaker 1: the membranes of your neurons. But it very slightly changes
Speaker 1: the way that information flows through these giant networks, and
Speaker 1: so who you are becomes slightly different. And drugs of
Speaker 1: all sorts influence our behavior this is obvious with narcotics.
Speaker 1: They slightly tweak the behavior of the network. And now
Speaker 1: you're talking to silver leprechauns. And I'll give you another
Speaker 1: interesting example of the influence of molecules. Take the professional
Speaker 1: wrestler Chris Benoit, who was this giant muscley guy who
Speaker 1: had a world heavyweight championship. And he went home one
Speaker 1: night in two thousand and seven and he murdered his
Speaker 1: wife and his son and he hung himself from one
Speaker 1: of the pulleys of his weight machines. Now, at the autopsy,
Speaker 1: they figured out he was on massive doses of the
Speaker 1: steroid testosterone and other anabolic steroids, and these can cause
Speaker 1: paranoia and violent outbursts, and it's known as roid rage.
Speaker 1: You change the exact balance of chemicals under the hood,
Speaker 1: and you change your decision making you change who you are.
Speaker 1: And by the way, these kinds of changes and who
Speaker 1: you are, these applied to prescription medications as well. Some
Speaker 1: years ago, physicians began noticing that some of their patients
Speaker 1: who had Parkinson's disease were becoming compulsive gamblers, and they
Speaker 1: were blowing their families money in Las Vegas or Atlantic
Speaker 1: City or online poker. Now, Parkinson's disease involves a decrease
Speaker 1: in a neurotransmitter called dopamine, and so the medications to
Speaker 1: help that they crank up dopamine levels and that makes
Speaker 1: the tremors and the rigidity go away. But dopamine also
Speaker 1: plays a second role in your brain, not just involving
Speaker 1: how your muscles work, but also in your reward systems.
Speaker 1: So it turns out that by ratcheting up the level
Speaker 1: of dopamine it was changing the decision making of the patients.
Speaker 1: It gave them a much bigger appetite for risk taking,
Speaker 1: and one of the ways this expresses itself is with gambling.
Speaker 1: So nowadays these Parkinson's medications come with a warning on
Speaker 1: the label that if you notice an increase in gambling
Speaker 1: or other risk taking behavior, then the dosage should be
Speaker 1: turned down. So what's clear is that the soul I'm
Speaker 1: total of your neurochemistry, whether from alcohol or drugs, or abuse,
Speaker 1: or steroids or clinical medications, whatever, these modify your behavior.
Speaker 1: So nowadays, what this all means is that when we
Speaker 1: talk about morality and decision making, what we're really talking
Speaker 1: about is the neural basis of this and this leads
Speaker 1: us to the very deep question about freewill. Is the
Speaker 1: mind separate from the brain or are they the same thing?
Speaker 1: And because of all the cases we have of brain
Speaker 1: damage and narcotics and disease states, and how people's behavior
Speaker 1: changes when their brain changes, it's a very reasonable hypothesis
Speaker 1: that you do not have free will. You are your brain.
Speaker 1: And although it's a mind bogglingly complex system, it's nonetheless
Speaker 1: a machine, a giant machine whose complexity we could never capture,
Speaker 1: but a machine nonetheless. As far as we can tell,
Speaker 1: every neuron that we measure is driven by the activity
Speaker 1: of other neurons, and those are driven by the activity
Speaker 1: of other neurons. So it's not even clear where that
Speaker 1: extra bit of free will would even live, what would
Speaker 1: make the whole machine not a machine. So try this.
Speaker 1: Whatever your sexual orientation is, go ahead and switch it.
Speaker 1: So if you're straight, become gay, and if you're gay,
Speaker 1: go become straight. Go ahead, I'll wait, Okay, good luck, right,
Speaker 1: Because free will isn't really what you might into it.
Speaker 1: It's not like you just make a decision about something
Speaker 1: consciously and then that's where things go. And this is
Speaker 1: the same with addictions and cravings and temptations. You can't
Speaker 1: just say, look, I'm the kind of person who doesn't
Speaker 1: like cookies or sex or food or whatever, and then
Speaker 1: that's how things go. There's a lot running under the
Speaker 1: hood that you have no access to and no acquaintance with. Now.
Speaker 1: I'm going to cover the free will question in much
Speaker 1: more depth in future episodes, but for now, I just
Speaker 1: want to say it's a bit of a difficult one
Speaker 1: to answer. Do we have absolutely no free will? Do
Speaker 1: we have a little bit of it? I think it's
Speaker 1: fair to say that most neuroscientists land on the position
Speaker 1: that we probably have none. Because every neuron in the
Speaker 1: brain is driven by other neurons, then it's not clear
Speaker 1: where you get the extra bit. I just want a
Speaker 1: flag that, given the available data, I think it's probably
Speaker 1: too early for us to conclude on this point with
Speaker 1: absolute certainty, because our science is still quite young. But
Speaker 1: what is absolutely clear is that if we have any
Speaker 1: free will at all, it is just a bit player
Speaker 1: in the system. The unconscious brain is the one in charge,
Speaker 1: and the conscious you is not driving the boat. So
Speaker 1: even if there is just a little bit of free will,
Speaker 1: just about everything you think and do and act and
Speaker 1: believe is generated by parts of your brain that are
Speaker 1: doing their own thing. Okay, so let's wrap up. What
Speaker 1: we've done in this episode is set up some foundational
Speaker 1: issues about how little we have access to what's running
Speaker 1: in our brains, all the activity that determines who we
Speaker 1: are and how we act what we believe. So join
Speaker 1: me next week for part two, where we'll ask how
Speaker 1: all this could or should affect the legal system. If
Speaker 1: we don't have free will or very little of it,
Speaker 1: what does that mean for the notion of culpability? In
Speaker 1: what sense are we responsible for our actions when there's
Speaker 1: so much running under the hood and so little conscious choice.
Speaker 1: We can't not take bad actors off the street, but
Speaker 1: how do we reconcile these two fields of neuroscience and
Speaker 1: legal theory. To find out more and to share your thoughts,
Speaker 1: head to Eagleman dot com, slash Podcasts, and you can
Speaker 1: also watch full episodes of Inner Cosmos on YouTube at
Speaker 1: inner cosmospod subscribe to see new episodes every week until then.
Speaker 1: This is David Eagleman signing off from the Inner Cosmos