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"Make Up Your Mind" premiered October 15, 2002

				How Phineas Lost It Scientists use modern technology to study Phineas Gage's infamous 1848 head injury.
		Select text to jump ahead in the clip: ALDA: This is the skull of Phineas Gage who over 150 years ago became one of the most celebrated cases in the history of medicine, which is why he's still here in the Warren Museum at Harvard Medical School. A smart and likable young man according to his friends, Phineas was working as the foreman of a railroad construction gang in Vermont when a blasting accident blew this three-foot long iron rod through his left cheek and clear through the top of his head. The rod landed about 25 yards behind him and Phineas got to his feet and walked away. As a local newspaper put it the next day, "The most singular circumstance "connected with this melancholy affair "is that he is alive and in full possession of his senses and free of pain." But while he lived another 12 years with part of his brain destroyed, he was, as his friends said, "no longer Gage." He was described as "fitful" and "grossly profane," on the one hand "impatient and obstinate," and on the other, unable to make plans for the future-- unable, in fact, to make up his mind. Phineas Gage's fame stems not only from his simply surviving such a ghastly accident, but because he was the first patient to suggest a link between personality and the functions of the front part of the brain-- the frontal lobes. In this show, we're going to explore how our frontal lobes shape who we are and how we go about our lives. But first we're going to find out exactly what happened to Phineas's brain when that iron bar blew clean through it on September 13, 1848. ALDA: The Gage skull is easily the most prized possession of the Warren Museum. Only members of the Museum staff are allowed to lay hands on it. Recently, a specialist in trauma medicine at Harvard Medical School began wondering how Phineas could possibly have survived the accident. The researcher asked for permission to examine the skull with the latest diagnostic technology, fortunately available right next door to the Warren Museum at Brigham and Women's Hospital. Phineas's day trip has brought him to one of the hospital's state-of-the-art CT scanners, more usually employed checking for disease in living patients. The puzzle he's here to resolve is one that has tantalized Dr. Peter Ratiu from the moment he first saw the skull in the museum. How could the rod pass clean through the skull and cause so little damage? RATIU: We know where the rod went, so the problem is that the rod is about twice as big than the opening, so it was a miracle enough that he survived. That would have been a direct godly intervention to stick a 1-inch rod through a half-inch hole. Now, how has that been accounted for up until now? RATIU: Nobody bothered to measure. ALDA: Peter Ratiu suspects that to let the rod through, the skull must have cracked and opened like a door on its hinge. ALDA: So the rod went in through here? RATIU: The rod went through here and entered the skull, and this is the most obvious crack. ALDA: Today Peter is hoping the CT scan will reveal a pattern of cracks in the skull consistent with his explanation for Gage's survival... That the rod actually opened the skull as it passed through-- the skin and tissue of Gage's face and scalp stretching for an instant, then snapping the skull closed again. Is that something you've experienced before? RATIU: Absolutely not. This guy skipped about five ways to die. Really? Yes, and each one is sure shot, so never try this. It's amazing. ALDA: While Peter Ratiu is interested in how Phineas survived, what's made Gage famous is how he later behaved. What's the area of the brain that was affected during this accident? Well, I think the area that everybody focuses on is the frontal lobes. Now, there might have been some damage to areas a little bit outside the frontal lobes, wubut whatww makes this person and their case interesting to scientists is the fact that the injury was in the frontal lobes and as a result of the injury, Gage's personality changed. Can we tell what kind of personality change? I mean, was it an inability to make decisions, or... it's hard to tell. It's hard to tell, other than the fact we know it changed. He couldn't resume ?Ihis former position, although he did work afterwards. But he wasn't good as a foreman. He wasn't good as a foreman, which requires executive skills. ALDA: I brought a brain in a box here, and I wonder if you can show me where on the brain the accident affected him? So these are the frontal lobes of the brain; this is the right side and the left side. And the rod probably entered somewhere from the bottom of the frontal lobes on the left side and came out somewhere on the top of the frontal lobes. So all the tissue in between here to here, no doubt, was damaged, as well as some of the surrounding tissue. What was the thinking in those days about the relationship of the brain to the personality? How did they organize their thoughts about that? Well, there wasn't a lot of sophisticated thinking. Here's an example of such thinking. This is a phrenology skull, and you can see etched into the skull in different places are what might be called "faculties." ALDA: Phrenology was invented by a very bright fellow called Franz Joseph Gall, who thought that different parts of the brain did different things. His mistake was in believing bumps in the skull reveal what lies beneath. Has any one of these areas shown to... You don't even have categories like this. Alan, it was a crap shoot, you know? Yeah, I mean, "benevolence." Nobody's looking for benevolence in the brain, are they? We're all looking for benevolence, but not right now in the brain. Reasoning faculties, he's got over here. So that's probably not a bad place to have it. There's probably some relationship between the functions of the frontal lobe and your ability to do certain kinds of reasoning. ALDA: He's got language under the left eye. Is that possible? I mean, is there...? ( laughs ) I mean, I'm saying is that possible, why would he say that? Is there brain under the left eye? I don't know what kind of plaster casts he was studying in order to do that. There's no... under the left eye is your left cheek. ( both laugh ) ALDA: Gall may have been wrong in the details, but his concept of the brain as an organ with specialized regions has been vindicated. And of all the specialized regions, none is more important in distinguishing us from the rest of the animal kingdom and from our pre-human ancestors than the enormously enlarged front part of our thinking brain-- the frontal lobes or prefrontal cortex. It serves as sort of the central executive-- the chairman of the board of the brain-- and it helps guide our behaviors, it helps us plan. It helps us carry out plans. It helps us reason about difficult topics. It helps us make certain kinds of decisions. It helps us inhibit behaviors that are not really appropriate, more primitive behaviors. For example, let's say you want to be on a diet, and you love chocolate, and in front of you you see this wonderful, delicious chocolate cake, but you know you shouldn't have it. So the frontal... So the back of my brain is... Wants it. ...wants it, and th de front of my brain... Is saying, "Not good for me." And so you're able to put it off, because you have another goal. Maybe the goal is to lose weight. Maybe the goal is to live longer. So these goals are going to be much more important than this sort of short-term goal based on just seeing that chocolate cake in front of you. ALDA: For much of this show, we'll be peering into our prefrontal cortex to discover how it works and how it allows us to be ourselves in ways that Phineas irrevocably lost that day he became "no longer Gage." If you were to look at any part of the cortex and say, what makes us human? well, we always look to language-related cortices, but I happen to think that it's the prefrontal cortex and the anterior part that makes us most human. Did you ever notice I have a tremendous shelf right there? And I'm impressed by that. ( laughs ) I know it's back to phrenology, but I'm... Whatever works. ( both laughing )

				Why Kids Don't Get It Adele Diamond's carefully designed experiments reveal how the brain's pre-frontal lobes develop in children.
		Select text to jump ahead in the clip: ALDA: The first stop for my brain and me is at the Shriver Center in Waltham, Massachusetts, which houses one of the leading laboratories investigating the minds of children. In the cheerful basement is a large room where kids of all ages hang out with their parents. We all know that kids' brains work differently from grown-ups' and it turns out, from work here ddand at other labs, that while much of a child's brain is up and running from the start, the slowest to come on line is the prefrontal cortex-- which, as we're about to find out, accounts for a lot. These kids look very comfortable. What are they here for? We give them games to play, problems to solve, which teaches us how they're understanding the world and how their mind is working. Every time they do something and they do it differently than us, they did it that way because it made sense to them. So we're trying to figure out how they're understanding the world and how their mind is changing as they get older, and the relationship of that to how the brain is changing. Now, this is supposed to be boring... ALDA: Adele Diamond frequently plays games with babies like ten-month-old Alexandra which are spellbinding in what they reveal about the infant mind. Okay, Alexandra, watch. Alexandra? Okay, where'd it go? Where'd it go? Where'd the toy go? Good job! Yeah, good job. ALDA: Like most babies her age, Alexandra finds this part of the game child's play. DIAMOND: Okay, hold her hands again. ALDA: But now Adele hides the toy a second time. Watch where it's going. Watch... Alexandra? Hello, watch where it's going. Okay, Alexandra. Good, where'd it go? Where'd it go? Where'd the toy go, Alexandra? ALDA: Alexandra seems a little bemused, but not half as much as I am. DIAMOND: Where'd it go? Look, look, it's over here. Yeah. Okay, let's try again. Okay, hold her hands. Yeah. Are you watching? Are you watching? ALDA: Despite watching intently as the toy goes into the left- hand well for a second time... DIAMOND: She's so sure of herself. It's amazing. ALDA: Now, what's happening there? Why does that happen? Well, what I think is happening is she's got only a very fragile memory of it being here, and she got rewarded for going here, so I think you have a battle going on between the fragile memory of where the toy went and this very strong impulse to go to what was rewarded before. So they go back. They go back. ALDA: Monkeys with damaged frontal lobes make the same mistake, suggesting it's Alexandra's immature frontal lobes that cause her to keep going back to the same old well. Good, where'd it go? Let's play this again, shall we? ALDA: By the time she's Graylen's age, Alexandra will be having no problem with the well task. But she'll still be doing things that to an adult brain seem baffling. And in the color game, all the red ones go here. All the blue ones go here, right? ALDA: Graylen is three. EXPERIMENTER: Can you point and show me where the blue ones go? Yeah, perfect. Where do the red ones go? Perfect. ALDA: The cards can be sorted either by shape or by color. Graylen is first learning the color game. Thank you-- good job. Okay, she has to match up the cards with the color of the objects. DIAMOND: Now she's going to do the shape game, where she has to match them to the shapes. EXPERIMENTER: Can you show me where the stars go? Yay. Where do the trucks go? Oh, excellent. DIAMOND: Now they won't be red or blue, so she can only match by shape in the cards. See? It's a yellow star. This is training. So remember, stars go here and trucks go here. Here's a truck. Where are you going to put that? Okay, so now she's done color and she's done shapes. No problem with either. EXPERIMENTER: Can you point and show me where the trucks go? Good job. Where do the stars go? Good job. Here's a truck. Where are you going to put that? ALDA: That was a blue truck. DIAMOND: Yes. Now it's the testing. So now she's got the conflict. ALDA: In the shape game, the color doesn't count and Graylen has learned the game well. Can you point and show me where the stars go? Excellent. Where do the trucks go? Yeah. Here is a star. Where're you going to put that? Remember, all the stars go in this box and all the trucks go... Notice on every trial either the experimenter restates the rules or the child answers, restating the rules. Show me where the stars go. Good girl. What about the trucks? Where do they go? She's learning, in a way, to ignore the color during this part. Yes, and then she's got to undo that. You know what we're going to do now, Graylen. Now we are going to play the color game again, all right? Now, remember-- in the color game blue ones go here and red ones go here. Can you show me where the red ones go? Where do the blue ones go? Excellent. Here's a blue one. Hmm... Yeah. EXPERIMENTER: Okay, remember, red ones go herand blue ones go here. Here's a red one. Where does that go? Have a look, and show me where the blue ones go. Excellent. Where do the red ones go? Excellent. Here's a red one. Where does that go? Wow. ( laughing ) Where do the blue ones go? Where do the red ones go? Here's a red one. Star. Right. It's really remarkable. What I think is happening is before the child sees the card, the child has clearly in mind what the rules are and what she's supposed to do. She knows that red goes here and blue goes there-- she's got it. Then she sees this card that's relevant to both dimensions in incompatible ways and that creates a problem for her. Here's a red one. DIAMOND: What we call this is attentional inertia. They can't get their attention off of what had been relevant before. ALDA: So what you start with seems to get dominance in some way. Now, why is that? Is it because it's been reinforced many times? I think so, yes. You've got used to doing those rules that way. ALDA: The part of the brain that's good at sticking to the tried and true is down in the more primitive regions. In the adult brain, it's the prefrontal cortex that jumps in and overrules the ingrained response. EXPERIMENTER: What is that? ALDA: But in a three-year-old brain like Juliana's, the prefrontal cortex still isn't up to the job of switching her mind to the new set of rules. Can you point and show me where the stars go? Where do the stars go, Juliana? ALDA: Adele Diamond has an idea she's testing here that if the child herself names the color or shape it will help get her out of the rut. Truck. Where do trucks go? Before, the experimenter said, "This is a truck." Now she's saying, "What is it?" and having the child say, "This is a truck." That's the only difference. What color's that? Red. DIAMOND: I think that it provides a verbal scaffold to help her move her attention. When she's named it as something else, I think that it helps her get over the hump of moving her attention to what's newly relevant now. That's what I think is happening. What color is this? Red. Where do red ones go? ALDA: For a moment it looks as if Juliana's got it... A little indecision. EXPERIMENTER: The blue ones go here. ALDA: But even with the verbal cue helping out... Can you tell me what color this one is? Blue. Where do blue ones go? Okay, she made a liar out of me. So this is the adult version of the child card sort that you just saw, and it's computerized... ALDA: Well, here's the inevitable moment when my prefrontal cortex is going to be on public display. Shape-- star. Wait a minute. ALDA: The word tells me whether to respond to the shape or the color. Shape-- truck. Shape-- truck. Shape-- star. ALDA: So far so good. When they're all shapes, my frontal lobes have it easy. Color-- blue. ALDA: When the rule changes, things get trickier. Color-- truck. Ah! Color-- red. Color-- star. No. ( laughs ): Color-- blue. Color... red. ALDA: Now the heat's really on. Sometimes the rule is color, sometimes it's shape. Color-- truck. Oh! Color... shape-- star. ( laughs ) Color... red. ( muttering ) Shape-- truck. Color-- red. Color-- sha... truck! No, color-- blue. ALDA: The computer's been measuring my reaction time which in the mixed trial slowed drastically. I am all washed up. DIAMOND: The children make the mistake at the level of accuracy. They actually get it wrong. Adults make the same kinds of mistakes but now at the level of reaction time. We're slower to do the things that the children do wrong. Now, what is this telling us about what's happening in the brain? In an adult brain, now, it's supposed to be totally developed. Well, maybe I'm on the downside again, I don't know. The older part of the brain-- the part of the brain that's involved with habit and doing what comes naturally-- has had a lot more time to develop than prefrontal. So fragile prefrontal cortex can't always solve everything. It's hard to switch. It's hard to change what your system has gotten used to doing. ALDA: This time my system is getting used to pressing the button on the same side as the gray dot, which isn't too hard. But now, of course, the rule changes. When the dot's striped I have to press the button on the opposite side and I'm slower. Then when the dots are mixed... Ah! Ah! Ah! DIAMOND: Everybody makes mistakes. I'm pressing everything. ( laughing ) If it was a... if it was a... If it was a pinball machine, I'd have done fine. MAN: Go ahead and lie down. ALDA: At least I got to do my test sitting comfortably at a computer. There you go... ALDA: Ten-year-old Kevin is going to do the same test while lying in an MRI machine-- actually a mock MRI machine, or his braces and maybe his teeth would be yanked right out of his mouth. Are my credit cards okay during this? It wouldn't be if it was a real scanner because of the magnetic field. But this is just like the real thing except that there's no magnet here so your credit cards are safe. This is what we use to get people acclimated to the scanner. Oh, I see, I see. Okay, Kevin, here we go. Here's your box. Put your hands on that. Hold your thumbs just like that, okay? Okay, I'll slide you in a little bit. ALDA: Kevin's prefrontal cortex-- as his parents will no doubt discover in the next few years-- still has quite a bit of maturing to do. TECHNICIAN: How's that? Great. Okay, so we'll get started here. ALDA: But when he performed this task in a real scanner, the images revealed a critical part of his prefrontal cortex already hard at work. ALDA: This is your brain? KEVIN: Yes. Do you recognize it? Yeah. So first what I thought I'd do is show you some of the anatomy of his brain. You're going to see us go from the front to the back, and as we're doing that, you'll see what it looks like at each of those levels. Pretty neat, huh? So these are the slices, Kevin, that we took through your brain when we were looking at the functioning of your brain when you were doing our task. ALDA: The area that lit up the brightest was up over his forehead and near the surface of his brain called the dorsolateral prefrontal cortex. DIAMOND: So this is how much harder his dorsolateral prefrontal cortex had to work when he had gray dots and striped dots. ALDA: Were you aware that it was harder? Did you see yourself, like, trying to concentrate on it? Yes. Yeah, it's harder when they're mixed together than when you just have one. ALDA: Would you get them wrong and then realize it a second later? Yes. Yeah, that happened to me all the time. And then I'd go, "Oh, no!" I'd get real excited. And you tend to see almost across whatever task that the more difficult condition you get activation of dorsolateral prefrontal cortex. When you have to concentrate, when it's hard, when you need executive control, you need dorsolateral prefrontal. The more you can go on automatic, the more you don't have to concentrate as much, the less you need dorsolateral prefrontal. ALDA: So your dorsolateral prefrontal cortex is critical to helping you make up your mind. But as we'll see in our next segment, it doesn't work alone.

				Tough Choices Princeton researchers study the brain's of test subjects making tough ethical decisions to determine which part of the brain is the seat of morality.
		Select text to jump ahead in the clip: ALDA: Our next stop, as my brain and I try to make up our mind, is the campus of Princeton University, where inside the department of psychology another test of my prefrontal cortex awaits. All right, so name the color and ignore the word. Okay, name the color and ignore the word. Name the color and... Yellow. ( all laugh ) Red. Blue. Green. I did it. ( laughing ) I'm so ashamed. Well, as we said, we want to see control and we want to see failure of control, right? ALDA: A classic in psychology, this is called the Stroop test. Name the color, ignore the word. Green. Yellow. Red. Green... blue! ( all laugh ) Yellow. Yellow. You did it. But I probably took three times longer. Describe what you felt when you were doing that. I just tried to look at it as some symbols that had a color and I was trying to read the color. And then at one point, all I saw was... I mean, my... I heard myself speaking what was written there, even though I had decided to just think of it as a meaningless... You scratched the itch. Yeah, well, it just produced the word in me. I want to look at this on my brain, okay? ALDA: If I'd been in an MRI machine at the time, no doubt my dorsolateral prefrontal cortex would have been glowing like crazy. But Jonathan Cohen is more interested in another part of the prefrontal cortex deeper down in the brain, which also seems to get involved when we're faced with inner conflict. COHEN: It's this strip of cortex right along here lying just over the corpus callosum which is this white area right there. ALDA: This brain region is called the anterior cingulate, which Cohen believes is watching out for those times when it's hard to make up your mind, when you're struggling to say red while you're seeing the word "green," for instance. The anterior cingulate then signals the prefrontal cortex to focus, focus, focus. ALDA: There's an organization to this tissue that's built in, that works that way, that helps you do that, that takes a recognized mistake and then on the next trial, sends stuff in that makes things a little better. I mean, this is built that way, from what you're saying. That's the hypothesis. I mean, in some sense, it has to be, right? The question is "how." And what we're trying to understand is how that happens. Just as an aside, one of my favorite books as a kid was a book called How Things Work. I don't know if you ever saw that. But it was a book that basically showed the mechanisms underlying all these things that we interact with in daily life. So you have a ball-point pen and press the clicker once and the stylus comes out. You press it again... And it goes back-- same click. Yeah. That's magic, right? And what was great about this book is it demystified that magic. It said how that happened. There's not a little guy in there keeping track. "Oh, we pressed it last time, it went out, so I better pull it back in." There's no homunculus. There's some mechanism that explains it. And the joy of science is discovering that mechanism. ALDA: It's not just when the brain's having trouble saying red instead of green that the anterior cingulate yells to the prefrontal cortex for help. Consider this classic problem in philosophy involving a train, or in some versions a trolley. You're standing next to a railroad switch as a train approaches. If you do nothing, the train will surely kill five foolish but innocent people standing on the track. You cold save them by hitting the switch, diverting the train. The problem is that there's another foolish innocent standing on the second track. So the moral question is, is it okay to hit the switch so that you only run over one person instead of five? What do you think? Off the top of your head. Off the top of my head. It seems, uh, you would. It would be regrettable to kill anybody, but if you could save the five people then you would throw the switch. Well, that's what pretty much everyone we ask says. Okay, now here's a slightly different case. Trolley headed towards five people. This time, there's no other track. You're on a footbridge standing over the track. And you're standing next to this big person. And this time, the only way you can save those five people is to push the big guy off of the bridge. He'll land on the tracks. He'll get squashed by the train. He'll die, but the five people will live. Okay, so would I push him off the bridge? Well, it's so hypothetical... I mean, I don't even understand. First of all, I don't understand how he could... I'd have to be really convinced that it could stop the train. But I'd be-- as I'm sure most people would be-- less inclined to push the guy. But, um, uh... I don't know... it depends, it kind of depends. I mean, do I have anything against this guy? Would it matter to me if I lost him? COHEN: A lawyer is what you really want. The fact that you're looking for all these sort of angles and ways out and things to question is very telling. Because most people are made rather uncomfortable by that one. Right, taking an active role. Structurally, these are very similar cases. I mean, it's death by trolley to one person in order to save five people. Perhaps you can try to find a reason for why it's okay and why it's not, and this is what philosophers do. We put the philosophical question about what's right and wrong aside for a second, and say, "What's going on in the brain?" ALDA: What they found when people struggled with these problems in the scanner is that regions of the brain thought to be involved in emotion lit up when people thought about pushing the guy off the bridge. And just as I did, it took them longer to make that decision than the less personal one of throwing the switch. The Princeton researchers also borrowed a story line from the last episode of M.A.S.H in their exploration of how the brain wrestles with moral dilemmas. A bus full of people has to hide from enemy soldiers. Quiet, now nobody make a sound until they've passed us. ALDA: But a crying baby endangers everyone's life. In the M.A.S.H. story, Hawkeye urges the mother to keep the baby quiet, and she ends up smothering it. In the Princeton study, subjects were asked to decide if its okay to smother the baby in a case like this. They were also asked about a second moral choice. GREENE: A teenage mother gives birth in the locker room at school and she just doesn't want to deal with it. Is it okay for her to just throw the baby in the dumpster? Almost everybody says, "No, that's not okay," and they say no very quickly. That's a personal case, in the sense of having that up close and personal interaction. It's the same kind of action, killing your own child, as in the M.A.S.H. sort of case. But very different in terms of what's going on in people's heads. In both cases, according to our view, there's a pre-potent emotional response that says no, no, don't do it. In the case with the teenage mother, because, at least according to our moral views, there really is no... there are no strong countervailing rational considerations that would make that okay-- you could probably come up with some if you modified the case a bit-- but there the thought is that the emotion occurs and it just wins, because there's nothing to oppose it. Whereas in the M.A.S.H. kind of case you have that pre-potent emotional response, but then your reason kicks in and says, "Well, wait a second. If you don't do this, everybody could die including the baby." So there's this drawn-out conflict, and instead of people answering it in two seconds or three seconds, they take closer to ten seconds to give their answer. ALDA: Josh Greene is now looking at the brain scans of people wrestling with the M.A.S.H. kind of case to see if the anterior cingulate, which the Princeton group believes is monitoring conflict, is working overtime listening to all the different parts of the brain, both rational and emotional, clamoring for input before someone finally makes up their mind. How emotion and rationality compete in decision making is also the subject of an experiment that I'm about to be suckered into, along, apparently, with some dozen Princeton students. Our subject today is going to be Alan Alda, whom I'm sure you all recognize, and slightly different from our run-of-the-mill Princeton undergraduate. And so the way it'll work is that each of you in turn will play one round of the game. You'll be brought into a room and sat in front of a computer terminal. You'll play the game with Alan who's going to be downstairs in the scanner. Alan, if you just kind of shake people's hands. Maybe you can just briefly introduce yourself and give your name. I'm Peter Vincenters. I'm a junior in mechanical engineering. How do you do? Hi, I'm Kathleen Mirand. I'm a chemical engineer. ALDA: Now, all I know about the game so far is that I'll be asked to accept or reject various financial offers each of these fellow players will be making. Hi, I'm Rob Wurtz, senior economics major. Finn Colabra, I'm a senior electrical engineer. How do you do? I got to watch out for the economics guy. ALDA: I'll be having my brain scanned while each of the other players offers to split ten dollars with me. I can either accept or reject the offer, but if I turn it down, we both get nothing. Well, if they give me a ridiculous offer, then I lose money because I don't accept their ridiculous offer? That's correct. If you reject the offer, neither of you get anything. This game is like life. ALDA: So it's into the MRI machine I go-- a real one this time. I'm given a button box to respond to the offers, which I can see projected onto a mirror above my face. TECHNICIAN: Alan, are you able to read the words "Welcome to the Experiment" on the screen there? ALDA ( over intercom ): Yes. ALDA: I hadn't expecteda computer as a partner, but its offer seems what a reasonable machine would make, so, okay, I'll take it. Kelly seemed nice... and she is-- fine. Kathleen, let's see. What? No, that's ridiculous. No way. I'm beginning to wonder if this is a setup and if the people aren't actually playing, just lending their faces. Aw, another selfish oaf. Take that. Claire. Yeah, she, uh... ( muttering ) Yes, no... no. Ah, the heck with it. I'm now pretty sure I'm being manipulated by the experimenters, not by those nice, polite Princeton students. Oh, here's the computer again. Maybe I can teach this thing a lesson in manners, too. Zap. Okay, after about 30 minutes in the scanner wrestling with my outrage-- freedom. Was there somebody live at the other end? SANFEY: Well, um, no. ( laughter ) Not exactly, no. At one point, they were alive when you took their picture. Exactly. Well, that occurred to me somewhere in the middle of the first run, I think. And did that... do you feel that affected the way you played the game? No, I played it as if they were real people. You actually rejected a couple of offers from the computer where it made, you know, avowedly unfair offers, but nevertheless, there's no... presumably there's no... Well, the chances were better for me if I assumed I could move the computer around than if I just had an emotional reaction to it. Or a very dry response, which is, hey, it's just a computer, what do I care? I'll take the two bucks and run. There's no consequences down the road for what I get. And, hey, it was only a couple of bucks... We discussed that, too. And at first we thought that maybe this is an inconsequential part of your salary. But then we realized, this is PBS. Maybe this is more than you're getting. No, I did very well today. But I haven't paid you yet. I know, they cut it by a... Worst part of the experiment. SANFEY: You want this right now? Yeah, I'll take it. Forty dollars. I suppose you think I'll be giving this back to Princeton, huh? Forget it. What do I have? One, two, three... What did I make? Forty-eight dollars. Forty-eight dollars. Not bad, huh? Now, of course, you know, it has nothing to do with the science of it, but how did I do compared to other people? I'll let these guys answer, because they're the ones... Is that about average? That's actually low. Most people would be... would reject less offers. ALDA: They would, because? What do they report when they talk to you? Why would they reject? Typically around the seven-and-three mark, people have typically told us, "Uh, it's a little bit unfair, but it's not too bad." So they'll tend to accept that. They'll also tend to accept everything a computer offers them. They don't really draw a distinction between fairness and unfairness for a computer. ALDA: That's interesting. Most of them will reject a nine-and-one offer and about half will reject the eight-and-two and most will accept the seven-and-three. Yeah, I must say, it would be interesting to know what you recorded when I was offered seven-and-three, because I thought, "Well, gee, "that's being awfully particular, isn't it? Why don't you take the three?" You know, but I thought, "No, no." ALDA: Decisions that mix emotion with reason are awfully hard to make, and the longer it takes-- if the Princeton team is on the right track-- the more that little strip of brain called the anterior cingulate is calling on your frontal lobes to resolve the conflict and make up your mind.

				What Happened at Jamestown? Ancient cypress trees help solve the mystery of the ill-fated colonists in the early 1600's. Forensic scientists investigate a colonial murder.
		Select text to jump ahead in the clip: ALDA: I'm traveling with an archeologist and a climate expert, and we're about to cross the James River in Virginia. We're heading for one of the last untouched bald cypress swamps in America, with trees that can be a thousand years old. The swamp may contain the key to understanding the terrible death rate suffered in the English colony set up on Jamestown Island in 1607. From our ferry, we could see the island, which, for the colonists, was apparently very badly situated. One of the English writes of... "We took most of our drink from the river, which was very brackish and makes us sick." ALDA: There could be a simple explanation for the bad river water. In drought years with very poor flow, the brackish and salty waters intrude well upstream of Jamestown. When the Indians visited them that one time and said, "You better start praying to your gods for rain," did they start to put two and two together then? Did they say, "Why... why should we pray for rain? Is something wrong?" I think they were flattered by that comment more than anything, because, in fact, what this Indian cheif said-- and he lived just upstream from here-- was, "In the same way that your guns and your ships "are better than our bows and arrows and our dugouts, "your god may be more powerful than ours. "So please pray to him for rain, because our god is not sending any." ALDA: Jamestown Island is just 1,600 acres jutting out into the river. It's about 40 miles from the southern end of Chesapeake Bay. The ancient cypress swamp is here, and we'll get back to that later in the story. But first we'll head to the island. In 1994, there was a major breakthrough when the colony's original fort was unearthed. My interest in this particular pieceof land here was the church site. And what you see there is a reconstructed church, but in front of it is a church tower from the 17th century. Did you think that fort would be near the church? Yeah, the first description was that the church is in the fort, then it's at the center of the fort. These are from historical documents. ACTOR: "A low level of ground about half an acre "is cast almost into the form of a triangle "and so palisadoed. "The south side next the river contains 140 yards; "the west and east sides, 100 only. "In the middest is a marketplace, a storehouse, and a corps de garde, as likewise a pretty chapel." ALDA: It had always been thought that the fort had eroded into the river, but Bill Kelso reasoned that if the existing church-- right behind him here-- is on the site of the original chapel, then the fort should still exist. Okay, this way a little more. Am I excited? You better believe it! ALDA: A private group-- the Association for the Preservation of Virginia Antiquities-- acquired the site in the 19th century to preserve the church. They agreed to let Kelso dig. KELSO: Here's a musket ball... and a piece of pottery. ALDA: Kelso's first shovelfuls contained colonial artifacts, and over the next three years, the shadowy outlines of post holes and walls were revealed. The fort, abandoned and forgotten by about 1625, had been found. We found holes that were dug in the ground where there were supports, but they were very small supports, and we think it was this crude at first. ALDA: What would this have been? Probably a barracks... because here you have a military outpost. ALDA: Kelso's teamtried reconstructing the fort's palisade. The colonists built their fort over just a few weeks, without the modern conveniences, when they were attacked by Indians soon after arriving. ALDA: You don't have other supports? You just have this stuff going straight in 18 inches? That's it. When you put these posts side by side, they support each other. And we also found that we had dirt left over, which would have been a shot platform. This would have acted to support one of those huge muskets. Oh, I see, so you have a little backing here with the dirt. You could be standing here. And also, this obviously is a little problem if you're worried about arrows... What about that? You could get arrows and shot through there. Well, we figure that they probably put saplings in there-- just pounded them in at this point. But up here, they'd leave it open because... They can shoot out. ALDA: As I was looking around the site, I thought there was something about Bill Kelso's story that didn't quite fit. This fence doesn't seem to encompass the church. It seems to go at an angle that won't include the church. Aha-- right. We were wrong. ( laughing ) The church wasn't in-- this church, at least-- was not in the center of the fort. But it's... you know, so what? ALDA: It was pure luck that the present church had been close enough to lead Kelso to the fort. Even with just an eighth of the fort area excavated so far, they've been able to build a picture of Jamestown's early days. WOMAN: We have evidence of what was known as "the starving time." That was the winter of 1609-1610, and most of the men literally starved to death. ALDA: These deliberate cut marks in horse bones are just the beginning of an appalling story. They had six mares and two horses before that starving time. They must have been pretty hungry to eat their horses. I mean, you're eating an important part of your life. Exactly-- their transportation. It's like eating your Oldsmobile or something. ALDA: Even though they ate everythingin sight, only 50 people out of 500 survived the winter. It's why the Jamestown colonists have often been dismissed as lazy and incompetent. They were clearly desperate. ACTOR: "Nothing was sparedto maintain life, "and to do those things which seem incredible "as to dig up corpse out of graves and eat them, "and some have licked up the blood which hath fallen from their weak fellows." ALDA: But far from being lazy or incompetent, it now seems the colonists were well prepared and industrious. STRAUBE: It's really unfair to portray the gentlemen who came here as a bunch of lazy, good-for-nothing guys who didn't want to get their hands dirty or blistered, Because we found a lot of evidence of things that they were busy doing, such as making window glass to send back to London. They thought they'd make a profit. ALDA: The colony was a straightforward commercial venture. The main objective was gold. This is a metal refining still. They made their own pipes, and raising tobacco was another objective. Their plan for subsistence was simple and realistic: trade for corn, using jewelry made from sheet copper that they brought with them. They knew the local Powhatan Indians prized copper highly. Initially, this strategy worked, but something went wrong. Indians stopped trading. Some attacked the fort. There were constant skirmishes. ( gunshot ) The fort site is filled with the leftovers of fighting. A couple of items showed up just in the short time we were there. This is a piece of chipped stone that's been flaked. But it's very distinctive in that these are really straight cuts. If this was natural, this would be more rounded. Probably American Indians did it-- probably to get a piece of stone for a projectile point. GAMBLE: This is probably... Well, this is. This is a piece of flint that the... or English flint that the colonists would chip off bits and pieces to use for their weapons. This is not natural to the area, but this is a good find. This is a good find. ALDA: The excavations also uncovered a mysterious casualty whose remains are being analyzed at the Smithsonian's Museum of Natural History by Doug Owsley and Ashley McCowan, forensic anthropologists. From radiocarbon dating, it's believed that this could be one of the first colonists. They called it JR102C. You have no idea what his name was? No, I wish we did. You would think he would jump out in terms of the historic record, but the record for this time period is such a black hole. ALDA: Here's what they can tell from "J.R.'s" bones. The pelvis says he's male. The skull dimensions and the straight tooth edges say he's European. The growth line in the leg bone says he's young, and the healthy teeth say he had good nutrition when growing up, so he was probably a gentleman. And there's one more thing. OWSLEY: His right leg, his shinbone, is completely fragmented, and in place was this round ball. This is a lead ball right here. So he got shot, huh? He got shot. And it was essentially like a combat shotgun type of load, because when you look at the X rays of it, not only was there this large round ball, but there are a number of small, buckshot-type pellets and also lead fragments. It practically blew his lower leg off. ( gunshot ) ALDA: The Indians didn't have guns in the early days at Jamestown. So what happened? The project set up ballistics tests using a reproduction of the type of musket the colonists used. ( musket fires ) ALDA: The big ball landed there, right? Over here. Yeah, there is your main shot. I was aiming right about here. ALDA: They're using a shot-load matched to the X ray of the young man's leg bone. There's one large ball with about 25 fragments. Here's a shot from 20 yards. ( musket fires ) SCHOLPP: So we've got... really a massive spread here. If this is typical of the kind of spread you get at that distance, then J.R. had to have been shot much closer. Closer range, absolutely. ALDA: Next, a point blank shot. MAN: Aim... fire. ( musket fires ) ALDA: That looked an awful lot like you were too close to be the... to come up with the pattern that J.R. had. Yeah, let's see what we got here.w omWe got unpleasantry. ALDA: Wasn't his spread out more? SCHOLPP: Yeah. ALDA: Next shot, at a range of five yards. ( musket fires ) And that's just about right. So J.R. couldn't have shot himself by accident, but maybe someone else shot him by accident. Fred Scholpp, the firearms expert, thinks he knows how it could have happened. It was standard fighting procedure for soldiers to fire from the front rank and then retire to reload. Someone in the rear rank could have made a mistake while reloading. Present your piece, give fire, retire. SCHOLPP: Don't point that thing at me! ( Alda, Scholpp laughing ) This is sort of from the front. ALDA: But J.R. was shot from the side. The angles just don't work out with Fred's theory. Different plane. I don't know. ALDA: Well, now what? Now... where are you with the theory now? What do you think? That's his theory. Oh, that's not your theory? My theory is that... it was on purpose and that, you know, like they say, "One less mouth to feed." Right. In times of stress, people are starving to death, and you resort to some pretty animalistic behavior. ALDA: We made it to the swamp, 20 miles from Jamestown. Okay, I'm going to watch. If you disappear, I'm not taking your path. ALDA: These magnificent bald cypress trees contain the simplest explanation for all the colony's problems. It just takes a little work for David Stahle to find it. ALDA: You know, I'm sure glad that you're here today. Otherwise, they'd have me doing this. ( hollow knocking ) We're not going to get much, fellas, not out of this one. ALDA: We're looking for an old tree, but one that still has a solid center. David Stahle is part of a network of scientists who study cores @drilled from ancient trees in order to reconstruct the history of climate. The Jamestown colonists said their water was bad. The Indians said there was no corn to trade. Maybe the colonists were incompetent, or the Indians were playing politics. But no, says David Stahle, there really was a drought. The annual growth rings in these cypresses record what the climate was doing in this region for the last thousand years. It's in two pieces, but... xxxxxkxThere you go. You can see you get about ten, twelve inches there of ancient cypress. But it looks like you get about 20 to here. I would say that outer inch has probably got more like a hundred. ALDA: Really? Yeah, I'd really be surprised if it didn't. Yeah, I may need a new prescription, too. ALDA: Actually, you need a microscope. Each pair of dark and light bands represents one year of growth. In 1607, as the colonists arrived, the region began its driest seven-year period in 700 years. And 20 years earlier, the worst drought in 800 years simply wiped out an English colony set up at Roanoke Island in North Carolina. ALDA: You mean to say that they came over twice, and hit the worst droughts in hundreds of years two times in a row? STAHLE: Monumental bad luck. I mean, phenomenal bad luck. Yeah, both... the two first English adventures in the New World were both beset by drought. ALDA: But the second adventure-- Jamestown-- succeeded. By 1612, the drought was over, and the colony began to thrive. America's first representative assembly met at Jamestown in 1619. Around that time, the first Africans were brought in to work in the tobacco plantations, probably as indentured servants. In the rest of the program, we're going to look at the consequences of that fateful development.

				The Power of Half Born with half a brain after suffering a stroke in utero, Michelle Mack's brain is capable of much more than her doctors ever expected.
		Select text to jump ahead in the clip: ALDA: We began our show rrrrwith the story of Phineas Gage, who lived without a chunk of his brain. We're ending with the story of an equally remarkable young woman. This is the right side of her brain. This is the left side of her brain. And what happened was when she... inutero, she had a stroke. ALDA: Yeah. And the stroke-- not entirely-- damaged a large proportion of her left hemisphere. So that never developed? Never developed. What's the left hemisphere usually there for? Verbal processing, language processing. Not all aspects of language, by the way, but enough that we consider it the hemisphere that really dominates our language abilities. It also plays a fairly large role in recognizing objects. Our ability to look at objects, to know what they are and even how to use them. So if those functions of the brain were only to be found in that area, then you'd expect that a person without that part of the brain would have difficulty saying words or recognizing objects. But this is not the case with Michelle? This is not the case with Michelle. ALDA:W Missing almost the entire left side of her brain, Michelle Mack has an obvious problem controlling the right side of her body. WOMAN: He'll think... when he comes in, he'll think... ALDA: But at the Catholic Church where her mother works, it's equally obvious that Michelle has few problems either with language or recognizing objects. She regularly helps out =DA: MICHELLE MACK: I take them home and I update them on my computer at home, and I bring them back to my mother and I file them. ALDA: Recently Michelle's mother, Carol, contacted Jordan Grafman at the nearby National Institutes of Health outside Washington, D.C. I wonder what testing Dr. Grafman will be doing. ALDA: Every month or so now, mother and daughter drive to the NIH to join Grafman and his team in a study of how Michelle's right brain copes with a workload most brains share with the left. Today, Carol told the film crew of a skill even Grafman doesn't know about. ALDA: If I say a date, you can come up with what day of the week it is? Yeah, I think so, yes. Well, let me just pick a... let me just not go too far out. Let's... let's say, um... let's say this year, the year 2000, October 19. Okay, October 19 is going to be on a... um... Thursday. Okay, I don't have a calendar, so I can't check that. So far you're doing great. Okay, so let me go a year later. The year 2001, August 12. Okay. Sunday. They're all checking. Are you? MAN: They're both right. They're both right. MAN: Oh, I'm impressed. ALDA: Well, you... maybe we should stop at 100% correct, right? That's amazing. Great, I hope this is on tape. ( all laughing ) ALDA: Did you know she had this ability? Not until right now. ( all laughing ) And that's why it's fun to work with Michelle, because she's always surprising us. ALDA: Jordan's work with Michelle is only beginning. TECHNICIAN: All right, now draw the design as accurately as you can. ALDA: But already it's apparent not only that her right brain has taken on tasks usually done by the left, but that it's had to make some changes of its own. For instance, Michelle has problems with tests of her visual-spatial skills, even though her right brain, where these are normally tackled, is intact. ALDA: It's almost a question of geography. Like there's a whole bunch of word people, who have no place to live on the left side, and they're crowding onto the right piece of geography. That's right. And there's only a certain amount of land there. They're not asking permission. That's right, they're coming in, they're barging in and the folks who are living there who handle spatial stuff are getting crowded out. Not as many of them can do their spatial stuff. That's what it sounds like is happening. Couldn't have said it better. But that's... that's fascinating, isn't it? I mean... I mean, there's this old saying that you hear all the time, of, you know, "Oh, we only use ten percent of our brains." It doesn't... it sounds like we're all using every bit we've got. Every bit we've got, and we'd try to stake more out if we could. Right, and it's almost as if there were parts of our brains competing for... Exactly. ...for a place to work. Exactly. As you learn new things, there's a... there's always somewhat of a cost. There's a finite amount of space and a finite amount of tissue, and you can enrich that tissue, but you're also going to compete with adjacent territory as you learn new skills and have new abilities. And you use the whole brain, and the whole brain is a competitive organ. Each piece of that brain is competing with its neighbors to get more territory, to have more action. And it's happening now, in you, and it's happening in Michelle as she takes the tests and develops throughout her life. ALDA: That's it for our show on how our brains make up our minds. See you next time.

Also, take a look at these related stories from the Frontiers Archive:

				Grow Your Own Brain Does running grow new brain cells and make you smarter? Research with mice yields some surprising results.
		Select text to jump ahead in the clip: where of all the brains in the world few have been changed more than the one behind the wheel of a London taxicab. No one can drive a traditional black cab in central London without first demonstrating "the knowledge"-- a mental map of London's maze-like streets. Man: Can you take me from Winfield House, the American Ambassador's residence to Old Bond Street? Leave by gate, left Park Road bear right Baker Street through Portman Square left into Wigmore Street right Welbeck Street... Alda: Scientists recently scanned the brains of 16 volunteer London cabbies and discovered that they all possessed a larger than normal hippocampus the area of the brain used for packaging memories before they're stored. Only months before an even more astonishing discovery had been made about this same region of the brain. Man: So, this is the imaging room where we... Alda: Fred Gage here at the Salk Institute in California led a team that found brand-new neurons in the hippocampus of Swedish cancer patients. Before they died of their disease these patients had volunteered for a study that labeled any newborn cells in their bodies with a bright-green dye. This is a slice of brain tissue from the hippocampus. Gage: The green corresponds to the molecule that was injected into the blood of this patient two years before they died. Which means that that neuron was born when the patient, in this case, was 62 years old. And at some later time point it became a mature neuron in their brain. That was a clear indication there were cells dividing in this mature person. Yes, yes. Alda: This discovery has set the field of brain science on its head overturning the long-established dogma that once we're adults we only lose brain cells, never gain them. There were not only cells dividing but cells that were becoming neurons in the adult brain. Alda: Today research labs all over the world are scrambling to understand the implications of this discovery. The starting point for much of this work was a study of rats done at the University of Illinois. When rats were raised in an environment that's more interesting and challenging than the usual lab cage their brain cells made many more connections. But there had never been any hint that they also made new neurons until Fred Gage and his colleagues set up a similar study with mice. Not only did they find new neurons once again within the hippocampus but mice living a more interesting and active life had more new neurons than did mice sitting around being bored. The mice had running wheels, as well as toys in the cage. To find out if simple exercise had anything to do with growing new brain cells the Salk team gave some mice just a running wheel. Woman: To our surprise we found that the mice that were housed just with the running wheel had the same number of newborn brain cells as the enriched environment suggesting that just physical activity or exercise alone can generate new brain cells. Alda: Having new neurons sounds good. But do they do any good? This is his very first time in the pool. He's never been in the pool ever before in his life. Alda: Henriette tested her mice for their ability to find a platform hidden just beneath the surface of the milky water. He doesn't even know there's a platform, huh? He doesn't even know... He knows nothing. Has he found it? He's found it, but basically, he's been lucky. Usually, it takes about two or three days for the mouse to learn this task and seven days of training for it to learn it really well to reach this... for me to put him in the pool and he'll swim to it in one straight line in two or three seconds. Alda: Henriette compared the time it took for both the exercised mice and mice housed in standard cages to find the platform. Place it in the water. Alda: Do they tend to go around the outside and then start to look at paths? Yeah, yeah. Whoa, he found it. It actually turned out very well for the mice on the running wheel because they managed to escape from the water faster in a shorter amount of time than mice housed under the standard conditions. So, this suggests that these mice have learned better and that they're... that they are smarter. Alda: So, running mice not only grow more new neurons; they also seem to be benefiting from all that extra brain. Have you started running? I've started and stopped running. ( both laugh ) But that's... we all do that! What... what... I consider... Did you start because of this? And why did you stop? I started because of my experimental results and because of looking at my slides with this dramatic increase in new brain cells. But it's... you have to be pretty disciplined to keep it up and, you know... and keep running every day. ( laughs ) So, are you maybe hoping that further experiments will show that you don't actually have to run? Maybe... maybe just rocking in the chair is enough to do it, you know. Well, what worried me was that these mice were running, like, 12 hours every night. And I wondered how... how could we run enough to even compare to that. That's right, sure. So, we did one experiment where we brought down the time of running to four hours every night for five days and we already found a 30% increase in cell division just after that short period of time. So, I'm hoping that we can bring it down to a shorter... To something we can handle. Right. Good-- call me when you find out. Alda: The task now is to find out just how running or an enriched environment creates new neurons. Growing cells in a dish outside the brain is one way the Salk researchers are exploring this question. These are brain cells actually dividing under the microscope. The hope is to discover the chemical signals involved and then find ways to use these chemicals directly to grow new neurons, perhaps even in the brains of people such as Parkinson's or Alzheimer's patients who have lost their neurons to their disease. In the meantime, I'll never think of my own brain in quite the same way again. Alda: There must be, in my brain right now a lot of stuff going on; birth and migration of cells and all... all... Am I right about that? Should I have a new picture of my brain? I think almost more remarkable to me than just the fact, which is remarkable enough that there's all this movement and plasticity that that movement and plasticity and adaptation that's occurring all the time in the brain is regulated by the behavior that you emit as an individual. Our brain controls the behavior but our behavior can also affect the structure of our brain which, in turn, is going to change how we behave. Alda: Which brings us back to those London cabbies again. Perhaps the reason for their enlarged hippocampus is that they are adding neurons with all that enrichment they're getting navigating London streets. Now, just imagine how much extra brain a cabbie might grow if he ran 12 hours a night! Alda:

				Monastery of the Mind Scientists explore the meaning of consciousness at the Neurosciences Institute in California.
		Select text to jump ahead in the clip: It's a place he likes to compare to older institutions with a fondness for hilltops. Man: Take a look around and look at this surrounding here-- it's like a cloister. So when the architects asked me about the place I said I want it to be a scientific monastery. I don't want it to be like a church. I want it to be a place where you can contemplate and look ahead 20 years. Now, in science, ten years is about as much as you can try to look ahead. Otherwise you're a crackpot. But we try... So you have them looking ahead 20? ( both laughing ) Show a little discretion here, yeah. Alda: Gerry Edelman has looked beyond the horizon for all his nearly 50 years in science. ( applause ) In 1972, he won the Nobel Prize for Medicine having succeeded at a task that daunted most biologists at the time-- figuring out the structure of the antibody molecule. He went from that to working on how living things grow and develop. And then he switched fields again, to brain science. Five years ago, he conceived of the Neurosciences Institute a place that would take on the biggest scientific mystery of all-- understanding the human mind. Which meant I was a little unprepared for my first stop at the institute-- to visit a modest and very unhuman machine roving around an indoor pen. Alda: What is this little guy doing in here? Well, this little guy, whom we call Darwin after a very famous biologist and because he's based on a similar principle to that of natural selection that Darwin invented is a creature or a device that's intended to simulate how the brain and the body work together. How they work together? How they work together. And the idea is something like this: It looks like a robot, but it is not a robot. You mean it hasn't been programmed to do specific actions? That's exactly right. There is no computer program telling it, go three steps turn to the right, if you see this, do that. Instead, like an animal, it's born a certain way has a brain of a certain kind and when it make errors it corrects the errors until it gets something that satisfies it. Alda: Darwin's brain is actually much too big to be carried around in its body. The brain occupies a supercomputer in the basement and keeps in touch with its body by radio. When Darwin was born it knew next to nothing not even that there are two kinds of blocks in its world: one marked with blobs-- the other with stripes. But like a newborn, it does have sight-- and a liking for things that taste good. Edelman: There's a gripper in front. The gripper is a little bit like your tongue-- it's in a peculiar position-- and it will sense electricity and conductance. So when it grabs a block it will get a "taste. " If the taste is bad it will drop that block and there will be a change in the strength of its nervous connections and, therefore, it will learn, as it were to stay away from a block with that shape. Alda: In Darwin's world, it's the blobby blocks that taste bad while blocks with stripes taste good. With just this built-in taste preference Darwin gradually figures out what it needs to do to live the good life. The brain itself is modeled on a mammal's brain with a visual cortex to receive the camera image and a second specialized area that interprets what it sees. In the computer, simulated neurons form a network with a quarter of a million connections. As Darwin blunders naively around its pen these neuronal connections begin to become organized. Here are groups of neurons firing together when it sees stripes. Entirely different groups of neurons light up for a blob. These neurons are in turn connected to motor nerves that control Darwin's behavior. And the rule is very simple: neurons that fire together, wire together. So that when the nerve cells or neurons are strengthened after it gets a reward that's more likely to make its behavior similar the next time. Alda: Darwin's brain is intended as a model for our own-- except that we have trillions upon trillions of possible connections instead of a mere quarter-million. We become who we are through the strengthening of some of these connections-- between neurons that fire together-- and the weakening of others. To Edelman, the brain is the ultimate gooey plastic capable of near-infinite possibilities molded by its experience into one of them. Even as we watch, Darwin's experience is turning it into a creature that craves stripes and rejects blobs on sight. Alda: Do you hit the reset button every few months and let him be born again to see how he... Oh, yes. Since it's very expensive to make 20 of them we generally wipe them clean and start again. And then you see how he learns with this new life that he has. And each one does it differently. Alda: Each one does it differently because its individual experience in its world is different-- the blocks are in different places and it encounters them in a different order. Each incarnation of Darwin's brain is shaped by its own particular life-- just as is ours. This makes it very different from even the most sophisticated conventional computer. Edelman: If you are going hunting for birds in a swamp on a rainy day and I gave you an Air Force computer and it was friendly and spoke English in a teacup would you take that or would you take a dog? ( chuckles ) That's... Right. That's what we're trying to understand. How does the dog recognize novelty? How do some dogs behave better than others when it comes to certain kinds of stimuli? And how does that relate to our very being as human beings which is the key question, of course, of neurobiology because it's at the center of human concern. Our brain and body are us. Alda: Lately, Gerry Edelman has been turning his thoughts to a mystery so profoundly personal that it has always seemed beyond the reach of science-- the unique world within our own heads we call consciousness. Edelman: We all know what consciousness is without having to ask a philosopher. It's what you lose when you fall into a deep dreamless sleep and what you regain when you wake up. So we have a sense of it, even if we can't put it into words. And so the problem is this: How do you make it a scientific subject? How do you actually investigate such a remarkable thing since it belongs to each individual to some extent privately. So is this an attempt to make it a scientific investigation? Exactly. Consciousness itself? It is indeed. It's to find what they call in the fancy language the "neural correlate" of consciousness-- what happens inside your brain when you become actually conscious of something. Well, Alan, let me introduce you to Lacey who is the lady who really knows how to work this thing. She's going to take you inside and expose you to this remarkable miracle of modern science. Okay, should I take my jacket off? Alda: I thought allowing scientists to eavesdrop on my dreams was pretty brave. Hello? Alda: But allowing a machine to peer into my consciousness? The plan here, as I understand it is to see what happens in my brain as my consciousness switches from an awareness of one thing to an awareness of another. What looks like a giant hair dryer is actually a machine for picking up the tiny magnetic signals my brain gives off as it busies itself interpreting the world. In this experiment my world is limited to the screen in front of me. To you it looks like a flickering plaid of blue stripes and red stripes. But the glasses I'm wearing limit my right eye to seeing only the blue stripes and my left eye to seeing only the red stripes. My brain can't handle these two different signals at the same time so it chooses to be aware of-- to be conscious of-- only one at a time. Every couple of seconds or so, it spontaneously switches. Now I'm aware only of horizontal blue stripes; now only vertical red ones. As I record which color I'm seeing the machine is recording which parts of my brain are responding. It turns out that neurons fire in response to both red and blue even when I'm conscious of only one. But there are many regions of my brain where the response to a color is much stronger when I am conscious of it. It's as if the blueness, say, is always there but springs vividly into my consciousness only when a vast network of neurons ignites together. So think of a kind of flame playing back and forth, back and forth. The flame is the consciousness, if you will but there's no one place where the consciousness is. Alda: The flame flicks between regions of the brain involved in memory as well as those processing new information from the senses. Edelman and his colleague Giulio Tononi have taken snapshots of this metaphorical flame in seven different subjects like me. At first glance, the flames look similar. But in detail, if you look at it, all people are different. Alda: The same thing is happening but it's happening seven different ways because you have seven different people. Like your seven different brain activity patterns when you are conscious. Seven different signatures when you sign something. And therefore... one of the remarkable conclusions we've come to is, I believe, non-trivial for human beings: individuality matters. Alda: There's an even more remarkable conclusion for non-humans. Having an idea of what consciousness is means you could in principle install one in an artificial brain like Darwin's. Now, when you synthesize it is it going to be like Alan Alda... certainly not. It doesn't have your body it doesn't have the same kind of structure. So it will be a consciousness. Now the question becomes: How do you check it? Yeah, I was going to say... If you can get Darwin... to be conscious How do you get a report from Darwin? You would have to have something like language. Higher order consciousness. Because otherwise you could only surmise that it was conscious. Alda: Knowing what consciousness looks like means you could also search for it in non-human animals. Edelman has little doubt that an animal such as a dog would turn out to possess at least the glimmerings of a consciousness flame. The difference between a dog and you, however-- or Giulio let's say-- is if you kick a dog the next time he may bite you or run away, but he doesn't sit around plotting to remove your professorship. ( chuckling ) Alda: We're ending our show on brain plasticity with a truly astonishing example. I'm with Jordan Grafman looking at the brain scans of a remarkable young woman.

				Decade of the Brain Frontiers stories which have probed the human mind over the past decade -- sleep research, memory, how kids think, and more.
		Select text to jump ahead in the clip: THE 1990s WAS THE OFFICIAL DECADE OF THE BRAIN AND ON FRONTIERS WE DID A LOT OF STORIES ON BRAIN RESEARCH: ON SLEEP, ON MEMORY, LANGUAGE, PHOBIAS HOW BABIES AND KIDS THINK AND LEARN. WE'RE STILL A LONG WAY FROM BEING ABLE TO SAY HOW THE BRAIN WORKS IN ANY COMPREHENSIVE WAY BUT WHAT HAS EMERGED IS A NEW APPRECIATION FOR HOW TREMENDOUSLY COMPLEX THE BRAIN IS WHILE AT THE SAME TIME BEING FLEXIBLE AND CHANGEABLE. IT DOESN'T SEEM TO BE LIKE A COMPUTER PROGRAM IN THERE THE WAY WE ONCE THOUGHT IT DID. ALTHOUGH MAYBE THAT'S JUST BECAUSE WE DON'T UNDERSTAND IT ALL YET. HERE'S JUST A SAMPLING OF WHAT WE FOUND OUT WHEN WE HAD OUR HEADS EXAMINED DURING THE FRONTIERS DECADE. ASKING THE QUESTION, HOW DO KIDS THINK ABOUT MAGIC OR ILLOGICAL THINGS, YIELDED SOME REVEALING ANSWERS. IS THAT HIGH ENOUGH? A LITTLE HIGHER UP ABOVE YOUR HEAD. HOW'S THAT?! Alda: IN ONE NOTABLE SERIES OF EXPERIMENTS BABIES UNDER ONE YEAR OLD WERE SHOWN ILLOGICAL EVENTS. EVEN MINDS THIS YOUNG SEEM TO HAVE MASTERED HOW THE PHYSICAL WORLD SHOULD WORK AS SHOWN BY AN ANALYSIS OF THEIR REACTIONS. ( crying ) WHAT'S IN THE BOX? Alda: IN CONTRAST, KIDS AS OLD AS THREE CAN'T YET RECOGNIZE HOW THEIR OWN MINDS WORK. LOOK AT THAT. WHAT ARE THEY? ROPES. Alda: JACOB CALLS THEM "ROPES" BUT THE POINT IS HE'S NOW SURE HE ALWAYS KNEW THEY WERE THERE. WHAT DID YOU THINK WAS INSIDE THE BOX BEFORE I TURNED IT OVER? ROPES. ROPES. PAUL, READY FOR THE INJECTION. Alda:: THE DECADE SAW TREMENDOUS ADVANCES IN WAYS TO LOOK DIRECTLY AT THE BRAIN'S ACTIVITY. PET SCANS WERE USED WIDELY REVEALING HERE, FOR EXAMPLE, LOWER BLOOD FLOW IN THE LANGUAGE AREA OF A DYSLEXIC'S BRAIN. I TRIED OUT THE LATEST OF THESE BRAIN EXAMINATION METHODS-- A FUNCTIONAL M. R.I.-- IN A STUDY LOOKING AT MEMORY AND AGE. Alan: HOW WAS MY BRAIN? IT ACTUALLY LOOKS VERY YOUNG. YES? YES. WHAT COULD YOU SEE? YES, WE WERE ADMIRING IT. Alda: THEY IDENTIFIED AN AREA THAT'S ACTIVE IN MEMORY WITH YOUNG PEOPLE, BUT NOT OLD. DRAWING TWO SHAPES WAS THE TASK IN A LESS HIGH-TECH, BUT NO LESS REVEALING, STUDY. NOTHING WRONG WITH THAT! Alda: NORMAL BRAINS CAN'T DO THIS BECAUSE SIGNALS TO THE TWO HANDS GET MIXED UP. WELL, WE'RE SEEING THE FACT THAT... THAT ALAN'S HEMISPHERES ARE CONNECTED. BUT A SUBJECT WHOSE HEMISPHERES HAD BEEN SURGICALLY SEPARATED TO TREAT EPILEPSY, CAN DRAW AS IF HE HAS TWO BRAINS. WE PUT ON THIS PIECE OF THEATER TO ILLUSTRATE SOME IMPORTANT RESEARCH ON THE UNRELIABILITY OF MEMORY. WHEN LATER I WAS SHOWN PICTURES OF THE PICNIC I COULDN'T REMEMBER WHAT I'D REALLY SEEN. Alan: UH... THAT'S A LITTLE... UMBRELLA? NO UMBRELLA, NO. Alda: I GOT THAT RIGHT... YES, I THINK I REMEMBER HER FILING HER NAILS. ALTHOUGH... BUT I GOT THAT WRONG. THE PICTURE IS ALSO VIVID IN MY MIND. BUT I THINK I REMEMBER HER FILING HER NAILS, TOO. I HAD A LARGELY SLEEPLESS NIGHT IN A SLEEP LAB SO WE COULD REPORT ON A STUDY OF DREAMS. I FINALLY SETTLED DOWN AT 6:00 IN THE MORNING. Man ( whispering ): THESE ARE REALLY GOOD EYE MOVEMENTS-- THESE ARE FAST AND THEY'RE BIG. Alda: THE RAPID EYE MOVEMENTS SHOWED I WAS DREAMING SO, OF COURSE, THEY WOKE ME UP TO TAKE A WORD ASSOCIATION TEST. IT TURNS OUT WE'RE REALLY FAST AT ASSOCIATIONS DURING DREAMING SUGGESTING THAT'S HOW WE MAKE DREAMS IN RESPONSE TO RANDOM SIGNALS IN THE BRAIN. Alan: NO, NO, I'M FALLING ASLEEP HERE. Alda: RECEIVING DIRECT SIGNALS INTO THE BRAIN WAS HOW DOWSERS CLAIMED THEY WERE ABLE TO FIND WATER. COMING UP ON SOMETHING. HERE WE ARE. 342 FEET DEEP. IT'S 26 GALLONS PER MINUTE. Alda: WE CHALLENGED SEVERAL DOWSERS WITH SCIENTIFICALLY BASED TESTS OF THEIR ABILITIES BUT, IN OUR LIMITED SAMPLE AT LEAST, NOTHING WORKED OUT. YET SOMETHING THAT SEEMED EQUALLY FAR-FETCHED APPEARED TO WORK PRETTY WELL USING BRAIN WAVES PICKED UP BY ELECTRODES TO STEER A SAILBOAT. ( electric drive humming ) AND, IN PERHAPS THE MOST UNEXPECTED STORY OF THE FRONTIERS DECADE IT TURNED OUT THE AIR FORCE WAS LOOKING AT THE SAME METHOD TO CONTROL FIGHTER JETS. IT'S SIMPLY A MATTER OF DESIRING THIS THING TO GO TO THE RIGHT OR DESIRING IT TO GO TO THE LEFT. AND THEN MY BRAIN AUTOMATICALLY PRODUCES THE SIGNALS NECESSARY IN ORDER TO MAKE IT HAPPEN FOR ME.