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Welcome to the recording of my first attempt at Facebook Live. I'm afraid that you will probably find this recording a little disappointing. In fact, I will not be offended if you start listening and you decide to turn it off. However, if you can take the time to listen and give me feedback, that would be greatly supported. The future success of this project is going to partly depend on listeners like you submitting questions ahead of time, even if you can't listen live. So the main thing that you need to remember is that moving forward, although the show is going to be recorded on the first Thursday of every month at 8pm Central Time, the topic is always going to be three months back. In other words, in April we were discussing January's episodes. In May we will be discussing February's episode, which was episode 142 with Michael Graziano about peripersonal neurons. And in June we will be discussing Elkanan Goldberg's discussion of creativity and so on. So I'm hoping that as time goes on, as people will be listening and knowing that this discussion is going to be coming up in the three months in the future that they will be, start submitting questions and I will also start paying attention to my emails more carefully for questions and comments that will help to create more interesting Facebook Live sessions. Thanks again for your support. Hi, this is Dr. Ginger Campbell. Welcome to our first Brain Science Facebook Live. Today we're going to be talking about episode 141, which went online in January of 2018. First of all, since I'm new to Facebook Live, I appreciate your feedback and suggestions on how to improve the experience. Obviously you can post your comments on Facebook, but you can also send me feedback@brainsciencepodcastmail.com I don't have a feel for how many people are going to join us in this live broadcast, but to give people time to tune in, I'm going to depart from my usual practice of saving announcements until the end. I'm going to give some announcements at the beginning to get people to sign on. But do go ahead and post your questions and comments. I will deal with them in a few minutes. Like I said, I'm trying to give people a chance to sign on. We are going to be talking about memory. That will be our focus today. I'm assuming that most of you are here because you're a fan of my podcast Brain Science, but for those of you who have never listened, I will take a few minutes to give you some background. Back In December of 2006 I launched two podcasts the Brain Science Podcast and Books and Ideas the goal of the Brain Science Podcast was to explore how neuroscience is unraveling the mystery of how our brains make us human. I was motivated by a desire to provide an accurate but accessible account that goes beyond the superficial hype one tends to find in the mainstream media. So I started out by reviewing the books I happened to be reading. But I soon discovered that interviewing scientists who wrote about their work was much more satisfying. So here we are 11 plus years later, and I'm hoping that Facebook Live will stimulate a new level of interaction between me and my listeners. But I expect that it's going to take a few months for word to get out. That's why we're starting today by discussing January's episode, which was 1:41. My hope is that many of you will have already had a chance to listen to that episode and be able to ask questions accordingly. Next month in May, we will talk about Michael Graziano's episode and his book the Spaces Between A Story of Neuroscience, Evolution and Human Nature. And then in June, we'll do episode 143, which was an interview with Dr. Elkanan Goldberg, author of Creativity the Human Brain in the Age of Innovation. So just a reminder, if you're listening now, please go ahead and put in your comments and questions and I will address them shortly. So what I'm going to start out today with, before I start doing listener questions and comments to help people catch up who might not be familiar with the episode, I'm going to highlight a few of the key ideas. We were talking with Dr. Rodrigo Quion Quiroga, who wrote a book called the Forgetting Memory Perception and the Jennifer Aniston Neuron. And the focus is, of course on memory. So the first thing that I emphasized at the end of this episode was that the principles that Dr. Quiroga writes about are those that we have discussed with several other recent guests. And one of the important principles is that our brain constructs our experience. Now, this is easiest to grasp when we think about vision because it's straightforward to document the gap between our perception and the information that reaches the visual cortex from the retina. If you're into numbers, you'll enjoy what he calls his back of the envelope calculations, where he says there's about 126 million photoreceptors in the retina of the eye that have their information funneled into about 1 million retinal ganglion neurons. Those are the ones that send the signals to the visual cortex. So that means at the Very beginning. The information that goes to the visual cortex has been limited compared to what actually hit the retina to start out with. He explains how this works in the book. And he also reminds us that at any one moment we only see a very small area clearly, even though we feel like we see all around us clearly. And he reminds us it's not the eye that sees, but the brain. Or to use the language of Lisa Barrett, it's the brain that constructs our perception of the world. Vision is the most studied, but the evidence is mounting that this process applies to everything we experience, including memory. Kiroga estimates that the average 35 year old has about 10,000 memories. But the key idea is that this is much, much less than the brain's theoretical capacity. During the interview, we spent a lot of time talking about why this is the case. The bottom line is that our brain is using its resources to determine meaning rather than to store irrelevant details. There's several famous clinical cases of people who could remember everything, but they had seriously impaired ability to think. For example, they could remember every detail of a story, but they couldn't tell you what the story meant. Talk about not being able to see the forest for the trees. The major focus of Quiroga's book is the discovery of the so called Jennifer Aniston neuron. Of course, he also found other neurons that responded to other specific people, including himself and other people working in the lab. He found a neuron that responded to pictures of Luke Skywalker and Yoda. But there are a few important things to remember about these neurons. One, where are they? They're in the hippocampus, which we know is important to memory. They're multimodal, which means they respond both auditory and visual inputs. And they're plastic, which means they can learn new things. So these neurons could learn new people. In the lab, it wasn't just old memories. The discovery of what he calls the concept neurons, which is what he would prefer to call the so called Jennifer Aniston neuron. The key idea is it should change the way we think about how memory works. Because we used to think that the role of the hippocampus is to be a sort of temporary storage until the memory gets transferred to the cortex. But these concept neurons suggest something else. They suggest that when one of these concept neurons is triggered, then that's what triggers the details in the cortex. Now, we can't test this directly because there's not a non invasive way to record from the cortex, but it does fit our current evidence. And if you think about it, it does fit our daily experience. So if I hear the word Jennifer Aniston, the name Jennifer Aniston, I might think about other characters on the show. Friends. But if you didn't ever watch Friends, her name might trigger covers of People magazine talking about her latest boyfriend. I don't know. Whatever. Another very important concept is that there's overwhelming evidence that our memories are repeated dynamically every time. And this is something we've discussed before. This episode does not make this new information, but it is important. Our memory is not as reliable as we like to think, and it's incredibly easy to create false memories. So, as he emphasized, our memories are not like a videotape. Instead, we store key associations that allow us to fill in the details as needed. It's very sobering to realize how incomplete and fragile our memories really are. But he emphasized that a better knowledge of how memory really works could inspire useful changes in our education system. Starting with focusing on a few key concepts rather than the quantity of material covered. That is just a few highlights out of this episode that I thought would be just a good way to introduce the subject. I do want to open it up now to questions from listeners. And I have one question that I got by email from Sue Choi was the most forms of meditation involve working with attention. Have you or anyone else studied the effect of attention on the function of these concept cells? Does the neuron get recoded, or is a new neuron encoded? Or do these concept cells coordinate differently with other neurons? These are great questions, which I unfortunately do not know the answer to. I can say something about the first part about attention, which is that there is a lot of evidence that attention is important to memory. In other words, if you're not paying attention to something, you're probably not going to remember it. This is something that those of us who are older are painfully aware of, because it seems like when you're young, that your brain's like a sponge and you remember everything that happens. And as you get older, it seems like things slip by and you realize, well, I wasn't paying attention, and I did not make a single memory in terms of whether or not a new neuron is encoded. I'm not sure the practical way of answering that would be very. It would be very hard because, as you may recall, the work of Quiroga. Well, let's just go back and talk about how Quiroga's work was done. He was working in concert with physicians doing epilepsy surgery, where they remove parts of the brain that are thought to be foci of epilepsy. So they have electrodes deep in the brain that are making these single cell recordings. They do this for about a week before surgery. The goal is to make sure that they don't accidentally destroy something important. And most of these people basically have volunteered to do these other experiments while they're waiting for their surgery. So it's a very short period of about a week that they make these recordings. This does teach us some things. For example, they learned that they could get responses to people in the lab that the person hadn't known at the beginning. So they learned that within a week, new memories or new concept cells, you might say, became active. They started responding to new things. So in that sense they were able to determine a certain amount of time course. But they are limited to the fact that this is a one time deal. They can't continue to make recordings from that same person even over weeks or months, let alone longer periods. So there's a lot of interesting questions that we don't know the answer to. For example, does a neuron get recoded? That is, let's say you're never thinking about Jennifer Aniston anymore. Does that same neuron become responsive to something else? That's a really good question. So being able to study memory at the cellular level in people is very limited. Now, most of the study of memory in people is not done at the cellular level like that done by Dr. Quiroga and his colleagues. Most of it is done by psychologists doing various behavioral experiments. The psychologists have been studying memory for many years. And one of the things I got out of Dr. Quiroga's book was that there was actually a scientist way back in the 30s and I apologize, I can't remember his name. I should be more prepared. But my sister has brought this unhousebroken puppy into my house in the last few days. And my preparation is not what I had hoped it would be. But anyway, this scientist back in the 30s actually demonstrated how easy it was to install false memories. This surprised me because I had always assumed that this was new when Dr. Elizabeth Loftus did it in the 90s. But it turns out the evidence that we could get false memories goes back many decades. And this is an interesting principle, actually one that I think Dr. Elkanah Goldberg sort of mentioned in episode 143 when he said something to the fact that if you think you have a new idea, the first thing you need to do is a literature search, because you're probably going to find someone's already discovered it. And one of the things that's commonly seen in neuroscience, and I'm sure this is true in other fields of scientists too, that people will have ideas and they will do experiments that don't necessarily fit the current paradigm. And so their work is ignored. And then decades later, somebody else has got a new idea and uncovers the evidence that somebody did decades ago. This was certainly the case for the evidence for neuroplasticity. Common sense says that there had to have been evidence for neuroplasticity around forever. Yet until a few decades ago, we were being taught that the brain never gets any new neurons and. But it's not plastic. In the case of memory, the key idea really is that every time we remember something, our brain recreates that memory and it incorporates everything we've learned since the last time we thought about it. And we can't tell when we've put new facts in there. And I don't know how many of you were around back when I talked to Robert Burton, way back in episode 44, I think it was, and we talked about the famous Challenger study in which they talked to people right after the Challenger disaster and asked them to write down what they were doing and feeling at the time of the Challenger disaster. And then they interviewed them again two years later. And only about 25% of them had memories that matched their original accounts. There was this one guy who just looked at his own handwriting and said, well, I know that's what I wrote, but what I remember now is what really happened. This is a very important study, not only because it shows how fragile our memories are, but it shows that something that has an extremely strong emotional content is not necessarily remembered more accurately, which is not our intuition. Our intuition is that if we had a strong emotion, then surely what we remembered was true. And I think the fact that our memories are not so reliable as we like to think is the important take home point in terms of tolerance to other people. I mean, how many arguments and fights have been based on people having different memories of what happened in the past? And then of course, there's the whole issue of the reliability of eyewitnesses, which, based on the science, it seems like the only account that the police ought to be using is whatever the person tells them the very first time that they're interviewed, you know, before they have a chance to talk to anybody else. Which of course is exactly the opposite from the way that our justice system currently works. Okay, well, I'm probably going to be signing off soon since well, I'm not entirely surprised that there haven't been more people online during this session. Although it's ironic that the other day when I did just like a five minute trial, there were more people online. But that was because it was the middle of the day and that's okay. Maybe I need to change the time of this to during the day time. I don't know that I'm open to that. My original intention was that whatever time I picked, it would be relatively inconvenient to somebody and that what I wanted to do was provide content that I could record for listeners to enjoy later. For that reason, I would like to encourage you whether you're listening to this now and just didn't want to comment whether you listen to it later. To keep in mind that moving forward, what I'd really like is to have questions and comments that I can use for this show. I'm not trying to make an effort extra episode of the podcast. I'm trying to give supplementary material which would be to address questions and comments people have. And like I said, in May we will talk about Michael Graziano's interview and the idea of peripersonal neurons, the idea that we have neurons that are very aware of the area right around our body and why that is so very important. So if you're out there and you just haven't commented, I appreciate you being here. And the next real episode of Brain Science will be released on the fourth Friday of this month. I'm not looking at the calendar right this second. Let me see. On the 27th of April, there'll be a new episode of Brain Science. It is an interview with Angela Friederici and we're going to be talking about language in the brain, a subject that is one I've wanted to talk about for a long time. So I hope that you will subscribe to the Brain Science podcast and check that out until next month. Talk to you soon. Thanks. Brain Science with Dr. Ginger Campbell is copyright 2018 to Virginia Campbell, MD. You can copy this show to share it with others, but for any other uses or derivatives, please contact me at brainsciencepodcastmail. Com.