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The show "Don't Forget!" premiered May 11th, 2004. Be sure to take a look at other episodes in the Frontiers Archive:

				Yesterdays Gone People with short term memory loss help Alan understand vital information about how we remember things.
		Select text to jump ahead in the clip: When I was 12, I went swimming alone in the surf down there. It was rougher than it is today. I was a strong swimmer, and for a while it was fun letting the waves pull me out to sea and tumble me over and over again under the surface. But when I tried to get out, I couldn't, and I started to panic and I realized I might drown. Eventually I was able to claw my way up the beach, grabbing at handfuls of sand. That was 55 years ago, and I still remember it vividly. I remember the waves pummeling me, taking me under, the wet sand under my fingernails, the roar of the waves. I remember the sting of the salt spray. So, where and what is memory? How is it tucked away in my brain, ready to come back in an instant? Tucked away along with, but separate from, hundreds of thousands of-- maybe millions-- of other memories? Where's the smell of the salt spray, the grittiness of the sand, the crashing on the rocks? In the next hour, we're going to find out how we create our memories, not just vivid ones like this, but where I left my car keys and the name of that familiar-looking person across the room there. And we'll be looking at how memories are lost, how as we grow older they become slippery and elusive sometimes vanishing forever, erasing our past and who we are. We're starting our exploration of memory a few miles up the coast from La Jolla, with a man whose own ability to create memories vanished almost entirely a decade ago. Ever since, he's been helping researchers from the University of California, San Diego. Hi. Good to see you, by golly. ALDA: Today, Larry Squire and Jen Frascino are on the latest of many visits the team has made to the man known to memory researchers everywhere as "E.P." Nice day today. FRASCINO: Oh, it's wonderful. We've got nice sun for the camera. ( all laughing ) We're going to go in. You're going to do some work with Jen. Good. ALDA: E.P. is now 82. In 1992, retired from a career in electronics, he suffered an acute virus infection that destroyed part of his brain. ...development, that's what I like. ALDA: Most of his thinking skills survived the damage virtually intact. Why should people pay taxes? To support your country and your counties and states to pay for things. FRASCINO: If you were lost in the forest during the day, how would you go about finding your way out? E.P.: I would find a river and follow the river down to wherever it may go-- ocean, lake... ALDA: E.P. can also copy complex drawings. About it, huh? ALDA: And he not only has no difficulty repeating back a list of words-- in this case, "dog," "raccoon," "lion" and "parrot"... Dog, raccoon, lion and a parrot. Good. ALDA: But even has a little sly fun with Jen along the way. What you got to add is about two more. Oh, really? Would that make it tougher? Then that would catch them. Maybe seven, you know. E.P.: "Leaf." "Medicine." ALDA: E.P. really hits his stride when the testing of his cognitive skills involves Jen's laptop computer. "Gold." E.P.: Having been in electronics over the years, I am amazed at all this. It's just wonderful, believe me. Little printed circuits, just, oh... You can't believe it. Used to be in a six-foot rack, and down to this, it's just wonderful. When I was in electronics, this would be in a six-foot rack... ALDA: But it's now that something odd about E.P.'s behavior becomes apparent. Printed circuits, diodes, triodes, and all that stuff in there, oh... Just amazing, believe me. When I was in electronics, this would be in a six-foot rack. This would be in a six-foot rack... This would be in a couple six-foot racks... Would be in six-foot racks... This would be in a six-foot rack, and now look at it, down to this, little printed circuits and... ALDA: So, he's not aware that he's told us three or four times that he used to be in electronics, that a computer used to fill a room and that now it's down to the size of a microchip... He's just not aware that he's said those things several times? No, he tells us the same stories again and again. We've heard these stories before, and we'll hear these stories again. The equipment that it takes... ALDA: How was it? How have you been enjoying this session? Oh, I enjoy this. Yeah. Absolutely. It is interesting, isn't it? Look at the work you guys are doing. You're getting wonderful, I believe. I'm sorry, I forget her name-- What's her name? Her name? Yeah. I don't remember. That's okay. Jennifer. BOTH: Jennifer. Jennifer. Jennifer. I'm sorry. Have you, uh... Have you met Jennifer before today? I think so. Yes. I'm not positive, though. I'm sorry, my mind... Oh, that's okay. We all have lapses. Oh, we all get that way. Oh, sure, sure. How much have you worked with him? We have probably visited his house 200 times. 200 times? And for him, is each time the first time for him? Well, you see, it's yes and no. It's clear that he does have a record of the experiences that are based on the habits of the interactions, the emotional values of the interactions, the fact that they've been positive and not negative. He certainly lets us in the door faster. I mean, like you saw, he couldn't tell you my name, he couldn't tell you if he saw me before. But there's definitely a rapport there that I think has been built, and he's aware on some level. I read you some words about 15 minutes ago. ( mutters ) Four of them. Four words. Do you remember me reading you four words? No, I can't recall. No? I'm sorry. No, that's okay, no need to apologize. My mind is getting old. That's okay. I read you four animals, and I want you to tell me "yes" if you think the animal was on the list I read you about 15 minutes ago, or "no" if it was not on the list. Okay? Cat. Yes. How sure are you? I feel reasonably sure on that. Cat. Uh-huh. Raccoon. No... no. I feel no. Giraffe. Yes. How sure are you that I read you that? I'm real sure on that. Real sure? They're a beautiful animal, believe me. Okay. Lion. No. Okay. ALDA: E.P.'s inability to remember things that happened just a few minutes ago can be traced directly to the damage the virus inflicted on his brain a decade ago. The areas destroyed were in his temporal lobes, most critically a structure called the hippocampus and the brain tissue immediately around it. Without a hippocampus, E.P. lives in a permanent present; anything new that happens to him simply doesn't get recorded. Do you remember drawing something for me today? No. Drawing something? About 15 or 20 minutes ago? No. Okay. No-- I'm sorry. Don't apologize. Thank you for trying. Thank you. ALDA: But although E.P. can't record new memories, old ones from the years before his hippocampus was destroyed are remarkably intact. He grew up in Hayward, California. How about your house on Castro Valley Boulevard to the Hayward Theater? Remember where the Hayward Theater is? Yes. I would leave the house and turn to the right to A Street. ( whispering ): This was in high school. ...to Castro Boulevard, then turn to the left and it's in the middle of the block. Hayward.... FRASCINO: Okay, and if you didn't go down to A Street, if you instead you took... you could take another street, what would you do? Oh, the center... Redwood Road-- Redwood Road would run right into it. ( whispering ): Unbelievable. How about the public library-- Hayward Public Library-- from your house? It would be the same thing-- going down A Street, and, uh... and, uh... A... you have to go to the left to B, and it's on the corner. ( whispering ): He's got that map in his head. He can see all these streets. ( whispering ): He used to ride his bicycle around. The last thing I want to talk to you about is the neighborhood that we're in now. Here? How about any of the streets around here? Can you tell me any of the street names in the neighborhood here? No, I... cannot. I... That's a tough one. Yeah. I'm sorry. No, you don't need to apologize. Oh... I know where Castro Valley Boulevard, but that's where I was born and raised. But right here, I have to say no, I'm sorry. No, I just live right here. Okay. Enjoy the world rather than... I enjoy our area right here. Okay. ALDA: You seem to enjoy your life. E.P.: Oh, I have... ALDA: The enthusiastic help of amnesics like E.P. has pinpointed the hippocampus as crucial for recording new memories. ...most places it was just... just wonderful. ALDA: At the same time, the fact that E.P. has vivid memories from years before his hippocampus was destroyed means the hippocampus can't be where they're permanently stored. We love it here. ALDA: It's to probe more deeply into how memories are formed that we're meeting another amnesic, but this time it's a man whose hippocampus, although badly damaged as a result of a heart attack five years ago, still struggles to put memories together. WOMAN: So, what I'd like to do is just show you some pictures and ask you what can you tell me about these pictures. Do they evoke any memory? What does it bring back for you? ALDA: Chuck's memory is being studied by Dr. Mieke Verfaellie. VERFAELLIE: This is something that you might have seen, oh, in any of the local newspapers in the last year. CHUCK: Well, it certainly has something to do with... people objecting to... ALDA: We're in Boston, where the recent sex abuse scandals in the Catholic Church have received intense media coverage. Um... people who are somehow hurting, abusing... not paying enough attention to others. VERFAELLIE: Good. Is that a picture that looks familiar to you? I believe this is a picture taken the day or days after the New York... the towers in New York were all... ALDA: Chuck? Do you remember where you were when that happened? CHUCK: Not at all. Um... I remember at the time being especially worried because my son was in New York and, obviously, the first thing... ALDA: As Chuck's wife remembersvery well, this isn't so. Their son lives in New York today, but he didn't on 9/11. Chuck taught English before his illness, and he's continued to write since, giving us a unique glimpse into a mind that knows only too acutely what it has lost. "I cannot remember my wedding day "or the celebration surrounding it. "I do not recall the birth of my sons, "my father's death, "or who most other family members are. And there are many." When we first came in here this morning, we actually started off with looking at some pictures. CHUCK: That's right. Do you remember... I knew you were going to tell me they were going to be there. Can I remember them? Um... Let me think, please. ( inhaling ) ( sighing heavily ) Hmm. I'm just getting glimpses. Not even any, uh... shapes or... actual depictions of anything that was there. Chuck certainly has severe damage to the hippocampus, but his hippocampus isn't gone completely. So there is still something working to some extent. And what happens is that some experiences-- some fragments of experiences-- may stick, but they're not linked in the correct way. They're not linked to other things that happened. They're not linked to the correct context. Sometimes they're not linked to the correct people. And so in that way we're left with fragments that are not integrated. Occasionally these fragments will pop up. They may pop up in seeing a picture. But, as he described it, he may also have sort of random thoughts and not know, "Is this really a memory or is it just a thought I'm having?" ALDA: Chuck's problem making a whole memory from fragments of his experiences fits with what Mieke Verfaellie and other researchers believe to be the main job of the hippocampus, not itself to store memories, but to link together the bits and pieces of an experience stored throughout the brain,-- sights, sounds, smells, even feelings-- so that they can later be recalled as a coherent whole. CHUCK: "I am missing pieces of a puzzle "completely incomplete. "I overflow, unfinished, "buzz hour by hour. "There is never a way to say "all I want to say. "Words buzzing around me "miss what should be. "Words: that hive of an alphabet, stinging me from 'A' to 'Z.'"

				Never Forget a Face Learn about the role of the hippocampus in storing memories.
		Select text to jump ahead in the clip: Let me give you a way to remember my name, okay? ALDA: So far we've learned about the role of the hippocampus from people whose memory is dramatically impaired. To probe deeper, we're turning to someone with the memory of a champion. ...something fell, right, okay? Add another l. ALDA: Frank Felberbaum worked with us a few years ago teaching a class how to put together a name and a face so we'd never forget them. So I've got a falling bomb now. All right, now, let's go... ALDA: Frank employs a method others in the memory business also use, making up highly visual stories that help glue together someone's name with a distinctive facial feature. What feature would you choose on my face? STUDENT: Your nose? My nose-- I knew he'd say that. ( all chuckling ) All right, so now, that's an easy one... ALDA: We wanted actually to peer into Frank's brain while he's remembering names and faces and see his memory in action. FELBERBAUM: ...all over my face, right? ALDA: How much time is he going to have in this test to remember names? He's going to have only two seconds per person. Which is a very short period of time. But can you actually do your thing in two seconds? I've never done it in that short period of time, so it's a brand-new experience for me. My new designer outfit... WOMAN: You look stunning. You look... I'm nude underneath. WOMAN: Well, you don't have to tell me that. ( laughing ): Okay? All right, so let's go ahead and bring you into the magnet room and make sure you're comfortable. ALDA: We brought Frank to a research scanner at the Massachusetts General Hospital in Boston. He's got a very young-looking brain-- it's beautiful. This view actually allows us to look at this folded-over gray structure, my favorite part of the brain, which is called the hippocampus. And you can see that in fact he does have what I'll call "plump" hippocampi, evidence that these are nice healthy hippocampi. For someone who's 66 years old, that looks great. You got to tell him he has plump hippocampi when he comes out. He's going to really... I mean... he'll just love it. It'll be a compliment. He won't even care what it means. Well, in this case, bigger is better. This is a size that matters, so his hippocampi look great. ALDA: It's Frank's plump hippocampi we're going to be checking on as he lies in the scanner and sees projected onto a mirror over his head a series of faces paired with names. He presses a button if he thinks the name and face go together, but the main purpose of this is simply to make sure he's awake and concentrating, because the task involves a staggering 455 face-name pairs, shown for only two seconds apiece. Meanwhile, the scanner is recording how hard his hippocampus is working. When you remember this morning and you remember being here outside the scanner and all of us, your hippocampus is putting together all of that information-- what it sounded like, what it looked like, who is talking, what you felt like. All of that gets formed in an associative or episodic memory. We're trying here to just tease that associative component out, of trying to say things that you haven't seen before-- that face and the name-- put them together. But that's just an example of what I think the hippocampus is always doing, which is putting together things into a cohesive memory. ALDA: So, the hippocampus turns out to be like a super-efficient file clerk, noting all the things that go into an experience as they're perceived in specialized regions of the brain and forming a network of associations between them. The question now is: How well did Frank's hippocampus work? Are you feeling okay? It's all right. Can you remove the bolts from my neck? ( laughter ) ALDA: After a half-hour rest, Frank is put back to work trying to remember which of two names actually went with the face he saw in the scanner. It's a long, arduous task, and for the first hundred or so faces, Frank seems to be cruising. ( no audio ) But as the faces parade by, Frank's success rate declines; after all, he'd had no time to use his own expert method to match face and name, and in the end he approaches the success rate of most of the subjects Reisa has run in her study, about 75%. SPERLING: So, that's somewhat amazing that you can remember three quarters of the face-name pairs you saw, 455, seeing each one of them for less than two seconds. That's amazing to me the brain can do that. ALDA: Even more amazing is what Frank's hippocampus was doing when he was in the scanner, because it lit up for face-name pairs he would later remember correctly, but stayed dark for those he'd forget. In other words, Reisa could, in theory, look at someone's brain while they're trying to memorize something and know whether they were going to succeed or not. It's now my turn to get my hippocampus scanned, this time while wearing goggles that project face-name pairs directly into my eyes. My task is a lot easier than Frank's. Here we go. ALDA: I get a full eight secondsinstead of two to look at each face-name pair, and Steve and Karen, it turns out, are going to become old friends, constantly cropping up among the new faces I'm seeing in the scanner. The idea behind this study is to find out if my hippocampus reacts differently when I'm trying to remember the new faces than it does when I'm confronted with dear old Steve and Karen again. SPERLING: That is not good here. WOMAN: Your hair-do looks great. You're a trouper. How was I? ( laughter ) ALDA: But first, the verdict on my brain. I've been scanned several times before for Frontiers, but you never know what's going to show up. SPERLING: Right here is the hippocampus, and you have no space around it. That's good-- very plump. I'm quite impressed. Whatever you're doing in terms of keeping your brain young, you're doing a good job. It looks great. Keep going-- this is Scott. It's not Sylvester. Okay... I don't know, maybe it is Sylvester. Wait a minute-- yeah, that's Sylvester. That's Sylvester. Yeah. ALDA: When it comes to recallingthe names and faces, my plump hippocampi seem to have been working pretty well back there in the scanner. ALDA: As it turns out, I get most of them right, though I had far more time and many fewer faces than did Frank. Brigitte. WOMAN: Excellent. And that is it. You're all done. Good job. ALDA: But the most interesting result again came from the scans. This time, my hippocampus lit up for all the face-name pairs, but as time went on, it increasingly failed to respond when Steve and Karen appeared. It's as if my hippocampus knew that I knew them, so it didn't bother to make the effort to remember. SPERLING: This is raw data, so it's quite messy, but if you look at it closely you can see that it started to go up during the first repeated face-name pair. You said, "Oops, I've seen this before," and it falls back down, saying, "My hippocampus doesn't really need to pay attention to this; I've learned this already." And we see this pattern very frequently. Again, it's most pronounced in young folks, and you've got a very young-looking hippocampus response there. FELBERBAUM: Me, too. Yes... absolutely.

				Why Memories Last Discover why we recall emotional memories more easily.
		Select text to jump ahead in the clip: ALDA: We've come to the campus of the University of California, Irvine to meet with one of the giants of memory research, Jim McGaugh. Jim has spent most of his long and distinguished career finding out why, among all the memories we form, some are vivid and indelible. Let's take the extremes-- extremes are easy. I'm sure that all Nobel Prize winners know exactly where they were and what they were doing when they got the news that they won the Nobel Prize, and they'll never forget that. I'm equally sure that people who pick up body parts after an airplane crash will remember forever having seen that, and when this is described by them, they call it... uh, "It's etched in my mind. "It'll be there forever. "I'll never forget this, it's ingrained. It's welded into my brain." These are the kind of expressions that are used. So at the extreme, whether it's highly joyful or whether it is terribly disgusting and annoying... Or frightening? Frightening, but it doesn't have to be frightening. It can be insulting, it can be insulting. I could say to you... which is not true, but I could say, "You know, "I read some of your stuff. "It's not as good as it used to be." You might give that some thought." Now, if you believed that I had said that, you'd remember that forever. I mean, what did I do? Was that frightening to you? As a matter of fact, every actor and probably every writer can remember every bad review he or she ever got word for word. Absolutely. I can tell you word for word my first bad review. ALDA: What makes these memories stick is their ability to arouse our emotions. Gun. ALDA: In this experiment, a volunteer is watching slides while her emotional response to each one is measured. WOMAN: An injured boy. ALDA: But the kicker will come after the slide show is over. TECHNICIAN: Can you name this slide? A decomposing dog. ALDA: The experiment was designed by Jim McGaugh's long-time collaborator, Larry Cahill. What does she know about this experiment? Uh, let's speak out here. She thinks this experiment is about emotion. So she thinks she's coming to an emotion lab where she's going to be shown a bunch of different slides of varying emotional content. Snake. And then immediately after she watches them, we're going to stick her arm in a tub of ice water. The reason we're going to do that is because this is a technique that's well known to activate the body's stress-hormone response. And we believe that the body's stress- hormone response acts to enhance memory. So by sticking her arm in ice water immediately after she views these slides, we should be able to enhance her memory. ( groans ) It's cold... How long can people take this? Many people, myself included, are wimps that can take it for about a minute. You know, what's amazing to me is that you're doing this thing with the ice after she looks at the pictures. She doesn't have to have her arm in there and be getting that... that burst of hormones during the time she's looking at the pictures. It's afterwards. Right now she's just recently acquired all this new information, 20 slides, but her brain is busy storing that information-- we call it consolidating, kind of like Jell-O setting. During the setting process, you have the opportunity to activate the body's stress-hormone response. And the stress hormones work on the newly forming memory to enhance storage of it. Go ahead and remove it. Very good, Malina. Just go ahead and put your arm here and rest it. You can take a three- minute rest period. During this time, I will continue taking measurements. ALDA: Malina endured the ice water for a full three minutes. How did the ice water feel? Horrible! Absolutely horrible. So you had an emotional response to it? Oh, yeah... yeah. ALDA: When subjects in the experiment are tested a week later for their memory of the slides, those who had the ice-water treatment, like Malina, remembered the emotional slides better than control subjects. Somehow the stress hormones had helped solidify the memories still forming in her brain. ALDA: Where does it take place in the brain? What do these stress hormones wash and activate? Well, we've done a lot of work in that regard, and in fact there's one region in particular that has been identified as absolutely crucial to these effects. It's a region called the amygdala. This person here would be facing towards you, and his-- or her-- amygdala is located about a half an inch in to an inch in either temporal lobe. It's the size and shape of an almond, and amygdala happens to be Latin for "almond." ALDA: Most of what we know about the amygdala comes from experiments with rats. McGAUGH: The animal's going to be put in the water for an opportunity to find a platform. It's never been in this water before, so it's going to swim around randomly. It'll be taken out after a while, and each time it's put back in, it's put back in at a different edge. Okay, so he ran into the platform, but it doesn't know that that's a platform. ALDA: From the rat's-eye view, the platform is invisible. The only way this rat is going to find it is by bumping into it. No, I'm not going to help you. ALDA: Most of the naive rats spend a lot of time swimming around the edges, looking in vain for a way out. So he's going to get a little clue. ALDA: It's a big clue. There is a platform here. When he looks up like that... Oh, he's looking. Is he using smell or wind or... Oh, yeah, he's using everything. He's sampling. He's sampling the environment. ALDA: Most rats learn to find the platform within a minute or so. But then some rats get an injection directly into the amygdala of a drug that switches it on just as stress hormones do. And now we're going to test for retention. Remember, it took him about 60 seconds on the very first trial. Wow. There-- that's memory enhancement. Wow! ALDA: So, by directly stimulating its amygdala, the drug caused the rat to have the equivalent of a deeply emotional experience, firmly fixing the memory of how to find safety. It's no coincidence that the amygdala in both rats and humans is nestled right next to the hippocampus. And it's the hippocampus, of course, that sets up the networks of associations in the brain that constitute a memory. The hippocampus is doing its job, and the amygdala comes in with a punch and says, "This was important. "Do more of what you're doing. Consolidate that more strongly." So, learning can occur without the amygdala, but it's not going to be very strong. And you would remember everything equally. You would remember everything equally, which is very bad. The death of your mother would be equal to where you put your car keys. Absolutely. Okay, and let's go. ALDA: But it turns out that not even all emotional events are necessarily remembered equally; it may depend on whether you're a man or a woman. Several years ago, Larry Cahill had subjects watch movies of emotionally arousing events. What I'd like to do now is to lay you down on this bed. ALDA: Immediately afterwards, their brains were scanned to see how their amygdalas responded. Recently, Larry re-analyzed the results of these experiments and discovered a puzzling pattern. In men, emotional events turn on only the right amygdala. In women, only the left amygdala is activated. Now, there's an old hypothesis that the right brain processes the gist of events while the left focuses on the details, so... Let's say a man and a woman are having an argument: "Did you pay that bill?" "I did pay that bill." "You never pay bills." "I do pay the bills." Whichever one is saying this about the other. The next day, if they said, "Let's go over what that was we had a problem with..." is it possible that we might expect the two of them to have a different way of remembering either the gist of it or the details of it? I would say it's entirely possible that while they were in the middle of that argumen