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Brainpower and Human Society

Aired September 23, 2012 - 14:00   ET



UNIDENTIFIED MALE: Essentially the lesson of modern neuroscience is that you are inseparable from their brain. So when you see someone commit a senseless act like a school shooting or a massacre like the one in Colorado, we can see and we assume that there is something abnormal about that person's brain even before we know exactly what that is.


DR. SANJAY GUPTA, CNN ANCHOR: Whether he's in the mind of a mass murderer or spinning tales of the afterlife, David Eagleman is messing with some of the most profound questions of our existence.


UNIDENTIFIED FEMALE: There isn't an area that David doesn't know something about, isn't interested in. He's a true polymath.


GUPTA: What is time? What is consciousness? How does the human brain construct reality?


UNIDENTIFIED MALE: We dropped people from a 100-foot-tall tower.


GUPTA: He'll go to almost any lengths to test his theory. So strap in. You're about to meet neuroscience and bestselling author, David Eagleman. He's a wildly creative thinker that will blow your mind just by explaining how it works. I'm Dr. Sanjay Gupta, and this is THE NEXT LIST.


DAVID EAGLEMAN, PH.D., ATTORNEY: The brain is a massive network made of tens of billions of cells shooting information back and forth, many times per second, every single cell, and each one is connected to others in such density that there are hundreds of trillions of connections in there.

I'm David Eagleman and I'm a neuroscientist. The neuroscientist studies the brain. In particular, I study the human brain. I'm very interested in the perceptual machinery by which we view the world and how we make decisions, our beliefs, or our actions in the world.

My laboratory is at the Baylor College of Medicine, which is the middle of the Texas Medical Center, which is the largest medical center on the planet. I have a number of students here. We have about 50 different projects on the plate.

UNIDENTIFIED FEMALE: He's a very high energy person, always is excited about the science we're doing, always looking for new ways to look at problems and ideas.

EAGLEMAN: The main them is how do brains construct reality? And so for that, we look at things like time perception and how your brain is putting together your notion of how things are happening in the world.

We also look at how different brains construct reality differently. For that we study something called "Synesthesia," which is a condition where people have a blending of the senses.

HANNAH BOSLEY, RESEARCH ASSISTANCE/SYNESTHETE: So for me what it means to have "synesthesia" is that letters and numbers are associated in my mind with different colors.

EAGLEMAN: Finally, we look at how this all matters on a societal level that there are individual differences between brains. A directive on neuroscience and law, and that seeks to understand how what we're learning in modern neuroscience will navigate the way we build our legal systems and navigate social policy. At night time, that's when I write.

UNIDENTIFIED FEMALE: He's written fantastic books, the best of which is some of his fiction work, which is fascinating.

EAGLEMAN: I wrote a book of fiction called "Sum," which was a very private, intimate experience for me to write that over the course of seven years. "Sum" is a book of 40 short stories, and each one takes place in the backdrop of a different possible afterlife.

When it finally did get published, it became an international best seller. It's in 27 languages. Then in 2012, it was turned into a full opera at the Royal Opera House in London and that was done by the German composer, Max Rictor.

SARAH ISGUR FLORES, ATTORNEY: There is no part of the world, society, science or anything that David really isn't interested in finding more about.

EAGLEMAN: Yes, I never had any down time. I don't really understand when people say that they're bored or they have nothing to do. There is so much to be done in this world. So I'm finding ways to fill up my time.

And what we did is we dropped people from a 150-foot-tall tower, and they're going in freefall backwards and they're caught by a net below going about 70 miles an hour. (END VIDEOTAPE)



EAGLEMAN: I dropped out of college after my sophomore year because there was so much that I wanted to do in the world, so I left college with no intention of coming back. I did several things during my time off.

I pursued a film career in Los Angeles, and I went off and volunteered with the Israeli Army, and then I studied abroad at Oxford University. But eventually, I decided I would come back and finish up undergraduate so I could then go on to graduate school where I could study the brain and get into some real depth.

I did my post doctoral work at the Salk Institute in San Diego and it's one of the best places in the world to be. It's a very magical place to do science. One of the people I met at the Salk was Francis Crick. He became a very important mentor for me.

Crick was the co-discoverer of the structure of DNA, which was one of the great biological discoveries of the 20th Century, but he was so much more than that. He revolutionized molecular biology. He turned to the problem of consciousness. It was sort of a taboo subject.

Because it was imagined that this feeling of private subjective awareness is somehow just an illusion and it took people with the gravitas of Francis Crick to say, you know what, this is a real scientific problem.

When I got to the Salk Institute, I started studying illusions of time. These issues about how time can stretch and warp and cases reverse, and Crick was such a fan of what I was doing there because he saw that those were important questions about our private subjective experiences.

We all assume that time is just a river that's flowing past, but what I've been working on for the last 12 years is this understanding that it's not just a river that's passively flowing. It's an act of construction of the brain.

When I was a child, I was eight years old, and I fell from the roof of a house under construction. And I was watching the brick floor coming towards me and I was thinking about how this is -- this must have been what it was like for "Alice in Wonderland" to fall down the rabbit hole.

But the point is that it seemed to take a very long time. I seemed to have lots of clear thoughts. And of course, as I grew up and I listened carefully to other people around me, I learned it was very common.

UNIDENTIFIED MALE: I was on my bike down on a hill. My front wheel flipped and that's when I fall down. UNIDENTIFIED FEMALE: I couldn't think, but I just remember like everything.

UNIDENTIFIED FEMALE: It felt like it was 3 or 4 minutes, and it probably was less because I wouldn't be able to stay underwater for that long.

EAGLEMAN: So that got me very interested because we're trying to figure out how time is represented in the brain and this is a critical piece of the puzzle. How does it happen that things seem to get stretched out, and does it actually run in slow motion for you?

Can you actually see something tumbling through the air or is it just a retrospective illusion that you thought it was so clear. There was no study on this because you can imagine how difficult it is to try to figure out how can you capture a subject right in the life-threatening moment and measure something about them.

So we had to home brew our own innovation. What we did was we dropped people from a 150-foot-tall tower and they're going in freefall backwards and they're caught by a net below going about 70 miles an hour. It goes against every Darwinian instinct that you have to fall backwards like that.

And we built and patented a device that we strapped to their wrist that flashes information at them in such a way that we can measure how fast they're seeing the world. The idea is that as you're falling, if you're actually seeing slow motion in bullet time like neo in the matrix.

Then you would normally be able to see things too fast, now they would slow down so you could see them just fine. What we discovered is that even though people think the fall took a much longer than it actually did, they did not see it in slow motion.

They could not see the information flash to them any faster than in a normal situation. So what we learned was this is essentially a trick of time judgment, of duration judgment, and it's tied into memory.

So when you have a very scary situation going on, you have other parts of your brain coming online that write down memories essentially at a higher density. The reason all this matters is because how the brain constructs time is something about which there is very little study.

But what's become clear is that this is so fundamental to how we perceive the world that if those mechanisms go awry, one will have a very fragmented cognition. "Synesthesia" is a condition where people have blending of the senses.

BOSLEY: So when I encounter a letter or number, I associate it in my mind with a color. For example, the word dog is d-o-g. It's also yellow, clear and green to me.



EAGLEMAN: The brain is just a three-pound biological organ that's in the darkness of the skull. And it doesn't see anything, it doesn't hear anything. All it has are these little windows to the outside world through the eyes, the ears, the fingertips, the chemical senses and it gets all this information in, in the form of electrical signals, and it constructs the world.

It puts together this reality that we have. There are many diseases and disorders that change the way people construct reality. And this is, for example, what visual illusions demonstrate to us. It turns out that we can induce, in the laboratory, the illusion that something happened before you caused it to happen.

One of the experiments we did in my lab a few years ago is we had people hit a button and that causes a flash of light. So you're the one causing the flash of light. But we inject a very tiny delay, just one-tenth of one second, so when you hit the button, there is a tiny delay before that flash of light happens.

Now we remove that delay so the light happens instantly, and you will believe that the light happened before you pressed the button. It's an illusory reversal of action and effect. The reason it's so important is because when I saw that, I thought, my goodness, that's exactly what happened with schizophrenic subjects.

They have a credit misattribution. So in the laboratory, we are pursuing this hypothesis that schizophrenia fundamentally is a disorder of time perception, and it's why they have auditory experiences because they're hearing a self-generated voice before they realized that they've generated it and then they have to attribute that to somebody else.

"Synesthesia" is a condition where people have a blending of the senses. "Synesthesia" looks something like this. Here's an experience of "synesthesia." The key is that it's automatic and involuntary. It's unconscious. It's an experience where normal stimulation to one sense ends up triggering an experience in another sense.

And the thing is that people with "synesthesia" are not being artistic or metaphorical or poetic, they are actually having a mental experience because of a blending in their brain.

BOSLEY: So when I encounter a letter or a number, I associate it in my mind with a color. For example, the word dog is d-o-g. It's also yellow, clear and green to me.

EAGLEMAN: It used to be thought this was very rare. We now know that it's quite common at least four percent of the population has some form of "synesthesia." I immediately recognized that "synesthesia" is a very powerful inroad into understanding aspects of consciousness, in other words, our private experience of the world.

Because what happens in "synesthesia" is there is a very tiny difference in the brain and suddenly your reality is different from my reality so I built an online "synesthesia" battery. It's an uncheatable battery.

People from all over the world can come and take these tests and so the way this works is you come to the site. You tell us the kind of synesthesia you have. Let's say you have colored letter synesthesia.

We present you with letter of the alphabet and a color palette where there are 16 million different colors that you can choose from. You choose exactly the color that best matches your synesthetic perception.

And then we present you the next letter at random and then the next and the next, and the idea is that you see every letter three times each in random order.

If you're a real synesthete, you have no problem picking exactly the same colors every time you see that letter. If you're faking it, it's impossible to remember exactly which color you chose the last time you saw that letter.

In this way we're able to sensitively distinguish who is the real synesthete from who is not.

BOSLEY: The main project I'm really working on is the genetics of synesthesia. The reason we think it might be genetic is because it tends to run in families.

So lots of times if you meet someone who has synesthete, they will have a mother or father or cousin or a sibling who also has it, too. So what we are trying to do is determine how the genetic makeup of that person could be related to them having synesthesia.

EAGLEMAN: When we find it, it will be the first example of a genetic difference between people that changes the way they see reality, how do very tiny genetic changes between us change the way that you see the world and I see the world.

So one of the things that we find in neuroscience is there is a lot of individual variability even though we always have a picture of the brain and we talk about the brain.

In fact, brains are like fingerprints. They're different in every person. Even though we like to think we can put ourselves in other people's shoes, that's not always possible neurally speaking. People are very different from one another.




EAGLEMAN: Anything we do to change the chemistry of the brain changes how people act. That part is clear in modern neuroscience. I'm interested in neurolaw because it's really where the rubber hits the road in neuroscience.

It's where we can take all the things we learn about human behavior and how humans are different and translate that into social policy, how we actually are running the system here. So we talk about the reasonable man standard.

What would any reasonable person have done in this situation? Now we imagine that all brains are essentially equal if you are over 18 and have an I.Q. of over 70 that there is sort of a standard, reasonable man.

But the fact is brains are so different from one another that people are not the same in how they calculate risk, how they make decisions, how they control impulses and so on. So for example, there are people with psychosis, a deep disconnection with reality.

For example, John Hinkley when he shot President Reagan had a delusion that he would win the love of Jodie Foster by doing this. He was not connected with reality. You have a completely separate issue with people who are psychopath.

They can harm other people without compunction because they just don't have an internal model of what it's like to be somebody else. So psychopath is somebody like Jeffrey Daumer or Ted Bundy. There are many other reasons why people can commit crimes.

People will get a stroke and do antisocial behavior. People will get a traumatic brain injury. They will come back from the war in Iraq or Afghanistan and they'll be criminals. Sometimes a brain tumor is involved.

So for example, Charles Whitman who climbed the University of Texas tower in 1966 and massacred people at random, it turns out that he had a brain tumor. He was killed that day and in an autopsy they discovered he had a brain tumor.

Now that we have non-invasive brain imaging technologies, we will be able to detect this sort of thing much more often. At some point, there will be a crime committed, like the Virginia Tech shooting or the Columbine shooting or the Aurora movie theatre shooting.

And we will find that the perpetrator had a brain tumor. I'm not suggesting that any of those events were explained by brain tumors, but at some point that will happen, and then society is going to have to deal with this very difficult question about this relationship between brain and behavior and this question of culpability.

I think we should plot five years around those years. So 1975, 1985, 1995, just keep sliding that window. If the effect goes away, that suggests it's just a demographic shift.

So I founded the initiative on neuroscience and law, which brings together neuroscientists and lawyers and epithets and computer programmers to figure out how modern neuroscience will affect the legal system. How we think about criminal behavior and criminal punishment and how we view things. They're five times higher than they were three years or after.

PABLO ORMACHEA, ATTORNEY: So it's a melding of all different viewpoints to try to see if we can understand better what's happening in the criminal process.

UNIDENTIFIED MALE: Murder and capital murder. Those are the biggies.

ORMACHEA: These are the biggies we really care about.

FLORES: The neurolaw is really important because we're at a very unusual crossroads in our system where we have an enormous number of people in the criminal justice system.

And yet we don't know exactly what's causing people to recidivate, to come back to prison, and when we can put them back in society and expect them to complete the rest of their lives.

EAGLEMAN: What we do, we incarcerate everybody. We treat jail as a one size fits all solution. Some people would be better off in a mental health facility rather than incarceration.

For some people, incarceration is just right, and some people are addicted to drugs and there's ways we can help them to break that addiction. That's one of the things we're doing in my lab right now.

We're using something called realtime feedback to help people take control of their addictions and break them.

Mark, next you'll see pictures of cocaine and you're going to crave when it says crave.

We put them in the scanner. We showed them pictures of cocaine and asked them to crave, and that gives the ability to image the networks in their brain what's involved in that craving.

So in other words, what they do is figure out what they need to do to squelch that craving in their brain and we're giving them visual feedback and they can practice this over and over again.

If this works, it's going to be a game changer because it gives us a way of saying, look, instead of jailing somebody because they're addicted to cocaine, what if we gave them a way to break that?

My ultimate goal is to make changes to the legal system, and I'm not going to be satisfied until we have changes to policy. I always tell my students, there are a million questions we can ask from this data, but only ask the ones that will lead to social change.

BOSLEY: Dr. Eagleman is great at getting students to be really excited about what we're doing. Working with Dr. Eagleman, people would do almost anything for science.

EAGLEMAN: Francis Crick once said the dangerous man is the person who has only one idea because then he will fight and die for it. What you really want is to have about 10 ideas because then they are willing to let them go.

I think that's a critical part of doing science is having lots and lots of ideas most of which turn out to be succinct, but there are a few gems hidden in the pile there and then that's progress.


GUPTA: What we've shown you today is only a fraction of the work that's going on in the Eagleman lab, but with every project, David is striving to decipher how each brain creates its own reality, and then to use that knowledge to create a safer and more just society.

That's what earned him a spot on THE NEXT LIST. Thanks so much for joining us. I'm Dr. Sanjay Gupta.