David Eagleman: Brain over mind?

so as far as we can tell were the only species that has thrown ourselves headlong into this game of trying to decipher our own programming language and so it would be as though your computer started to control its own peripheral devices and pull off its cover and pointed its webcam and its own circuitry and try to figure out what it was made out of that's the situation that were it that we're in now and what we have found under the hood is the most complicated thing we have ever found in the universe so the human brain is three pounds it contains tens of billions of neurons neurons are the specialized cell types in the brain and every neuron is about as complicated as the city of New York it contains the entire human genome in it and its trafficking millions of proteins and these are connected to each other in such density that it bankrupts our language and we have to invent new types of mathematics to even address this there are so many connections between these neurons that numbers in the hundreds of trillions and it means that if you took just a cubic centimeter of brain tissue there are as many connections in there as there are stars in the Milky Way galaxy so it's a tremendously complicated system but the part that's really strange is that somehow this vast wet biological network is you it's all of your hopes and your dreams and your aspirations it's the agony and the ecstasy it's all contained in this stuff that's kind of alien to us right and the reason we know this is true and it's not contained and let's say your pinky is because if you were to damage your pinky in a car accident you would be sad about it but you'd be no different as a person but if you damage an equivalently sized chunk of brain tissue that can change you entirely that can change your decision-making you risk aversion your capacity to simulate possible futures and evaluate them or your ability to see colors or name animals or understand music or 100 other things that change when your brain changes and that's how we know from hundreds of years of witnessing mother nature's cruel experiments with with stroke and tumor and brain damage of various sorts this is how we know that this is the densest representation of you it is the basis of your decisions in your personality and how you act in the world and who you are now even stranger is that essentially the entire operation of this the most complicated system we found runs entirely under the hood of conscious awareness it runs invisibly to you so so when I pick up a cup of coffee that's actually underpinned by a lightning storm of brain activity to make that happen to get the grip force right and the muscles and the joints I'm not aware of any of that all I'm aware of is whether I spilled a coffee on myself or not and the rest is totally invisible and in fact the early neuroscience pioneers pointed out that if it weren't for our study of the brain you wouldn't even have any reason to suspect the existence of electrical signals and nerves and tendons and muscles and so on because it's completely invisible of course it's not just lifting a cup of coffee it's everything that we do in life it's getting a joke recognizing a friend's face or falling in love driving a car anything we do is running underneath the hood and we have very little idea about how we're doing it and this is what leads to the idea of the unconscious brain and it turns out that the conscious mind the part of you that flickers to life when you wake up in the morning that's the smallest bit of what's happening in your brain that's the broom closet in the mansion of the brain so so think about when you have an idea and you say oh I just thought of something it wasn't actually you that thought of it right I mean your brains been working on that behind the scenes for hours or days consolidating information evaluating things trying things out at some point it's ready it serves it up to your conscious brain and you say oh I'm a genius it wasn't really you right so it turns out that the conscious mind is like a stowaway on a transatlantic ship that's taking credit for the whole journey without acknowledging the massive engineering that's underfoot as Carl Jung put it in each of us there is another whom we do not know and as Pink Floyd said there's someone in my head but it's not me so let me give you an example of this there was a study some years ago where men were asked to it to rate the attractiveness of women's faces and photographs so they would look at the photos and from 1 to 10 they would rate how attractive they thought they were what the men didn't know is that in half of the photographs the woman's eyes had been dilated with some eye drops and it turns out that the men uniformly ranked the pictures with dilated eyes as more attractive but the important part is that none of the men said oh yeah I noticed that her pupil was a millimeter larger over here none of them noticed that consciously and presumably none of the men knew that dilated eyes is a biological sign of sexual readiness and women but their brains knew it group and here they were running the right sorts of decisions running these deep evolutionary programs that steered their behavior in the right way without them having any conscious access to what was going on there and it turns out the unconscious mind has tremendous influence on all the decisions we make in life as an example if your name is Dennis or Denise you are statistically more likely to become a dentist now you can prove this to yourself you can prove this by going through the professional dental registries in any state and showing that there's an over-representation this is because of what psychologists call implicit egotism we like things that remind us of ourselves it turns out you even like people better who share your birthday even though that's totally arbitrary anyway you'd agree that this is a terrible reason to choose a life profession right but there it is and if you ask any of these Dennis's or Denise's why they chose dentistry they would have some sort of conscious narrative about how it's a good profession and they like teeth and so on but what their narrative would be missing would be these unconscious influences and it's not just things like life professions it's even who you choose as your lifemate you can prove to yourself by going through the marriage registries in any county that you are statistically more likely to marry someone whose first name begins with the same first letter as your first name so Joe and Jenny Alex and Amy Donnie and Daisy it's a small statistical effect but totally verifiable and it's a terrible reason to choose a life mate right and if you ask them they're conscious narrative about how they chose this person that's probably would not be included but there it is it turns out they're influences on all sorts of very important things we do in life and and these can be pulled out in the laboratory very easily for example if you're holding a mug of hot coffee you will describe your relationship with your mother as closer than if you're holding an iced coffee strange but true and it turns out there are these unconscious signals all the time to change how we perceive our relationship with the world so there's this enormous gap between what our mind has access to and what the brain is actually doing under the hood and the circle back around to the main point the issue is that when we look at the wetware under the hood it's completely alien to us it's it's made up of the strange alien landscape of neurons and synapses and chemicals of all sorts and yet somehow that strange material maps on to the decisions that we make and our behavior and our personality what we take to be reality that's the situation that we find ourselves in and so this simple fact this equivalence between this alien stuff that we don't have access to and the way we behave in the world leads us right into the heart of some very deep ethical questions which I want to address here so let me give you a few examples of this and we'll go right into the landscape here so many of you are probably familiar with the story of Phineas Gage for those of you who aren't he was a young railroad worker in the 1880s and there was an explosion that blew and iron rod through his head and the rod clattered to the ground 50 yards away and the reason it became a famous medical case is first of all because he didn't die which was unusual he didn't even lose consciousness but it's because his personality changed entirely that's why I became a famous case instantly as soon as this part of his prefrontal lobe was stripped away he became a different person and people who knew him said gage is no longer gage used to be a sweet young man that everyone liked now he cusses and he's a pathological gambler and he sleeps with prostitutes and he's just a completely different person so this is one of the first very clear cases where people said wow when your biology changes you change also you are somehow irrevocably yoked to this three pounds of tissue who you are what people love about you how you make decisions it's all tied into this now that was 130 years ago and in the meantime we've had a lot of Phineas gages I'll give you an example some of you may remember in 1966 Charles Whitman who climbed to the top of the tower at the University of Texas at Austin and he began to indiscriminately open fire on on people below he shot pedestrians he shot the people that came to help them he shot the ambulance drivers who came to help them and in total he killed 14 people and wounded 39 others that day and the police finally were able to make it to the top of the tower and kill him and the first thing they wanted to know is who is this person and they went to his house in Austin and discovered that the night before he had killed his wife and his mother and he had sat down at the typewriter and written what has amounted to a suicide note so the only thing that was stranger than this incredibly random act of violence was that there was nothing about Whitman that priests aged his sort of behavior he had been an Eagle Scout he was he was high IQ he was an engineering student at the University of Texas he worked as a bank teller there was nothing in particular about him that would have indicated he would have ever done something like this and so everybody wanted answers and it turns out when they read his suicide note they discovered that Whitman also wanted answers he described in his note and also in his diary that he'd kept carefully for the last year that something inside of him had been changing and that he felt that he was victim to all sorts of angry thoughts and and and urges that he'd never had before and he wanted to do something about it he went to a psychiatrist in 1966 but it didn't do any good it didn't help him and he said in his suicide note when this is all over I want an autopsy to be performed and that's exactly what happened and they lifted his brain out of the vault of his skull and they discovered that he had a brain tumor it was brain tumor that was pressing on a part of his brain called the amygdala which is involved in fear and aggression and it was another example that when the brain changes you can change also here's an example from more recently this was in the medical literature it was a 40 year old man who had a normal sexual appetite and started becoming a pedophile he started collecting up child pornography becoming obsessed with this at some point he made an inappropriate move on his prepubescent stepdaughter in the house and his wife had him arrested and the night before sentencing he was having these worsening headaches so he went to the emergency room and they did a brain scan on him and what they discovered was that he had a massive prefrontal tumor he had a tumor it was it was growing and it was changing his personality they removed the tumor in an emergency surgery and his sexual behavior returned completely to normal and the story has an interesting PostScript because about eight months later he started showing signs of pedophilia again his wife took him back to the doctors it turns out they had missed a part of the tumor which was now regrowing so they resected the tumor a second time and his sexual behavior returned to normal a second time so what these demonstrate to us is you are tied to your biology and there's no way you can escape that and when you think about who you are the kind of decisions you make it is a function of what's going on under the hood and of course people have always known this I mean all over the world people will pour ethanol over their mucosal membranes to make themselves funnier to party and things like that and people use drugs of all sorts which changed their personality this is Chris Benoit who was a worldwide worldwide Wrestling Federation champion and he went home one night and killed his wife and his son and then hung himself from one of the pulleys of his weight machine it turns out that his doctor had conspired with him to give him eight times the normal levels of testosterone that a man is supposed to have and and he was having a roid rage it completely changed his cognition some of you may know the story of what's happened with Parkinson's medications several years ago it was noticed that some of these patients who are on Parkinson's medications were starting to become pathological gamblers and they were blowing their family's fortunes in in Las Vegas and upon investigation it came to be understood Parkinson's involves a neurotransmitter system called dopamine and dopamine is involved in the motor problems with Parkinson's but it's also a molecule that serves a double duty in the reward systems in the brain and when you change the levels of dopamine that changes people's risk aversion and it can turn people into pathological gamblers and so now it's one of the warnings on the label it says if you become a pathological gambler you know you just titrate the dosage here so if you ever think about if you ever think about okay well I'm the kind of person who you know who makes terrific decisions and I'm not a gambler you have to understand that it's a matter of what's going on in your biology and what I think all this comes down to is that nowadays when we're talking about morality and decision making what we're really talking about is the neural basis of this and this leads to a very deep question which is the question about free will are we free to choose how we act or are we as the is the mind equal to the brain well I think what's clear it's it's not it's not known whether we have free will or not this is a hotly debated topic but what is very clear is that the unconscious mind is the one that's in charge and the conscious bit on top is not the one driving the boat and that most of how you feel and how you act and how you behave and what you believe to be true all this stuff is being generated by systems under the hood that you have no access to and very little acquaintance with even that's the situation when we look at when we look at things like what you're attracted to and how you feel about other people and the kind of personality you have the kind of decision-making you do and hundreds of things like this what seems clear is that if Free Will exists it is a small player in the system you're tied to your biology if you don't believe it use your free will to to change your sexual orientation so go ahead good switch it right good luck good luck because you're tied to your biology and we don't have as much play in the wheel as we like to believe we have when it comes to free will now all of this leads to a really deep question which is if so much stuff is running under the hood what does this all mean for our responsibility in the world and what does it mean for the way that we run our social policy well the legal system is we have it now rests on two main assumptions the first one is that we are practical reason errs this is the term of art that means that we are free to choose how we act in the world we get to walk into a situation and use our freewill to navigate our behavior around and the second assumption is that all brains are equal meaning if you're over the age of 18 and you have an IQ of over 70 then it's assumed that all brains are the same in terms of capacity for decision making impulse control the ability to simulate possible futures and evaluate them and so on and that's a very charitable assumption but it's demonstrable false because along any axis that you measure brains you find there's a very wide variety and this is because brains come about as an interaction of genetics and environment every environmental experience you ever have and this sends brains off on very different developmental trajectories and as a result all brains are very different just like faces in the room just like fingerprints everybody's gaana but they're very different from one another and so neuroscience suggests that these are not very good assumptions and the problem with these assumptions is that it's led us to treat incarceration as a one-size-fits-all solution and as a result of that America is the number one country in the world for the percentage of our population that we put behind bars this is concerning because Prison is provably criminogenic which means it causes more crime you put people in jail you break their employment opportunities you break their social circles they have high chances of coming back around and the estimates now are that 30% of our prison population has mental illness which means that our prison system has become our de facto mental health care system this isn't the right place for us to be putting our mentally ill and you know this kind of system of putting everybody in jail it's not cost-effective and it has very low utility for solving anything now it turns out one thing I need to make very clear is that as we get deeper biological insight into the differences between people and why they behave differently this does not excavated is the capacity to do rational sentencing to do customized rehabilitation and to do realistic incentive structuring instead of imagining that everyone responds the same to the same sort of deterrence in fact people's brains are different and people respond in very different ways and the thing is we all talk about and agree on things like tailored education so why not have tailored social policy it turns out it's so much more cost-effective to front-load at the beginning and understanding of why very different people may have committed the same crime and how to navigate intelligently through the system into the future from there there's a real need for understanding this this is from Whitman's suicide note he said if my life insurance policy is valid please pay off my debts donate the rest anonymously to a mental health foundation maybe research can prevent further tragedies of this type very haunting I think and this is what led me to start some years ago the initiative on neuroscience and law which brings together neuroscientists and judges and lawyers and decision-makers to to understand what's happening at the intersection of neuroscience and the legal system and I'm just very briefly going to mention the kind of things at the intersection here for example drug addiction we put drug addicts in jail now we spend 40 billion dollars a year on the war on drugs and it's totally unwinnable because we're attacking drug supply and if you press supply down in one place it's going to pop up somewhere else if you want to address drug problem you have to address drug demand which is the brain of the addict and we know so much about the circuitry in pharmacology at this point of drug addiction my colleagues and I all over the world we're doing a lot of work to figure out how to help drug addiction in a way that we don't have to put people in jail for it but instead we can help them the insanity defense is something that's at the intersection of these fields is always in flux lawyers and legislators need a better understanding of the reality of mental illness brain death is another point of intersection part of the brain can die while part is alive and then the legal system has to make this question this this is this decision about when you declare somebody dead and modern technologies with brain imaging are allowing us to look into the brain and answer that question in a better way eyewitness testimony one of the worst technologies we allow in the class in the courtroom and yet it has the most sway on jurors and then the other thing we're studying is the effect on jurors brains and how jurors make decisions which is the other half of the equation and why they're hardwired for attributive ISM and when it makes sense to try to override that so if anyone's interested in more on this go to new law org I just want to say one thing in closing here which is that sometimes when we look at the brain and we and we realize that it's a little scary that we're not the ones at the center anymore we're not the ones driving the boat that feel scary to us but in fact I think there's a nice historical analogy here which is in 1610 when Galileo discovered the moons of Jupiter and discovered we weren't the ones at the center of the orbits that was decried as a dethronement of man from his position at the center of things but these Romans have an upside which is we came to understand that the whole universe is so much more grand and wondrous and subtle that we could have ever imagined back when we thought we were at the center and I think exactly the same thing is happening in cognitive science which is that as we sail into this inner cosmos and discover all these alien life forms what we realize is that what's happening there is so much more grand and wondrous and subtle than we could have ever imagined and the bottom line is that we have found the most amazing thing in the universe and it is us thank you very much for attention fantastic

Channel: poptech

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Keywords: PopTech 2012, brain, mind, neuroscience, science

Id: UWBtT-Gl4vQ

Length: 22min 25sec (1345 seconds)

Published: Fri Apr 19 2013