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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