Ep14 "Why do we have so little access to what’s happening under the hood?"

Published Jun 26, 2023, 10:00 AM

Who is doing the choosing when you make a choice? Is there someone in your head but it’s not you? What is a chicken-sexer, and what do they have to do with British plane spotters during WWII? Do we have free will or don’t we? Dive in to discover the ways in which you typically operate with no conscious access to your behaviors.

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

Inner Cosmos with David Eagleman

Neuroscientist and author David Eagleman discusses how our brain interprets the world and what that  
Social links
Follow podcast
Recent clips
Browse 99 clip(s)