BBC Sounds Music Radio Podcasts Hello and welcome to Made of Stronger Stuff with me, Kimberley Wilson. And me, Zand van Tulleken. I'm a medical doctor by training and Kimberley is a psychologist. And in this podcast, we take a tour around the human body. We're picking out a single body part each time and asking how we can understand it better, ourselves more, and how we can use that knowledge to create positive change. This time we are back in the brain and that is great news if you love complicated things because we're going to be looking at a little almond called the amygdala. Can I just tell you what I know about the amygdala? Sure thing. Okay, good. So I think the amygdala is our lizard brain. It's the bit, this is the... Oh, don't start shaking your head already. I said I was willing to be wrong. Okay, so here's the common story about the amygdala. It's an ancient part of our brain that is involved in fear and immediate responses that are sort of fight or flight. It's dinosaur brain basically. And that is the sum total of what I think I know about the amygdala and I think it's probably wrong. Well, we get into a little bit of trouble at the idea of a lizard brain to start with. So that what you're describing, that triune theory of the brain, that there are three parts of the brain, an old, middle and young part, doesn't really stack up in terms of modern neuroscience. And actually most of modern neuroscience has thrown away that triune theory of the brain. So I'm willing to give it up. So we relinquish the triune theory of the brain and then we have the amygdala or the amygdalae because there are two of them, these almond shaped little clusters of nuclei, either the side of the temporal lobes on the side of your brain. So if you point to it, it's just sort of just behind your eye where your temple is, if you know where that is, right? Yeah. It's one of the few areas of the brain that people kind of talk about much more colloquially and that if the amygdala is involved, it's probably to do with fear. That is our big common association of the amygdala in terms of our emotional life, that it's about fear, stress, trauma, and lots of the research literature has found these associations, like differences in morphology, so the shape or size of the amygdala in different populations of people. So people who might have had experiences of trauma in the past, people with anxiety disorders, there are lots of correlations between the size, the kind of relative size of these people's amygdala and their diagnosis or their diagnostic category. So I'm wrong that the brain has evolved by sort of building more bits around the amygdala, but it does seem to genuinely be associated with fear, anxiety, anger, aggression, and kind of reactions to those sorts of things. It's even more complicated than that. It's involved, but probably not in the way that most of us think. And I think that's really what we're going to get into the nitty gritty of in the rest of this episode. All right, so notepads at the ready. We'll meet our first guest now who has a unique window into their amygdala and a very unusual relationship with fear. I was probably 25, 26, driving home from school and thinking, oh, I am going to die. I am going to die one day. Like that's really going to suck. This is Jodi Smith from New York. And for the next 24 hours, barring a few hours of sleep, I was just stuck on this loop of I'm going to die one day and there's nothing I can do about it. Like the next day in class, I'm like, oh, OK, so algebra three squared, I'm going to die. Four, I'm going to die. I mean, that's how I feel when I do algebra. But OK. I'm going to die. This is killing me. Certainly, people become very aware of it in midlife. It's what we call the midlife crisis, that kind of facing of your mortality. I feel like we all have it. But even the thing you're describing, which I've definitely had probably since I turned 40, an evaporation of the belief that I was going to live forever, which is what I previously secretly believed. Whereas Jodi is saying something that's obviously true but seems to have a very disproportionate engagement with it. Yeah, he can't get this idea out of his head. And we often get that and often we can brush it off and just go back to our normal activities, the other things that distract us from this constant awareness of our mortality. But for Jodi, things started to change and his fears would occasionally feel really intense. And he would have this sense of impending doom. And then one day, Jodi was alerted that something was definitely wrong. At my grandma's July 4th party, which is not a rowdy event, we're all just sitting in a circle and I start feeling that something's about to go wrong, something is wrong. So I get up and start walking. And that's the last thing I remember, just kind of like darkness and my mom saying something. But I don't remember any of it until the emergency medical services come by. Jodi was diagnosed with epilepsy. He'd been having regular seizures and after seeing doctors and getting several scans, they decided it would be safest for him to remove the parts of his brain that were causing the issues. That's when they decided that right hippocampus had to go, the right amygdala had to go, and the front half of the right temporal lobe would be the right amount to take out, not too much, not too little. So there's a lot going on here. There are parts of the brain that are involved in lots of different processes, memory, emotionality. And of course, Jodi was understandably nervous. I am my brain. You cut out a piece of my brain, I'm going to wake up as like a different person maybe. Fully, understandably terrifying. So after a lot of deliberation, he decided in the end it was worth it because the seizures were, they're going to be damaging his brain anyway. So he went through with the surgery. And the size of the pieces that they took out was about a half pack of cigarettes worth of brain. That's quite a bit, isn't it? It's more than I would want to lose. So what happens then? So as you might expect, Jodi did notice some changes when he woke up. I very quickly realised that my speech inhibition was through the floor, gone. I was just talking everyone's ears off and I knew it. It was really strange to me because the urge to talk was so powerful. It was like I needed to pee, but peeing was talking. So there were the immediate changes, but Jodi also noticed some major differences a few weeks later. I'm just watching a movie and I see the reference of like, life begins as one cell. This in the past would have been something that sent him spiralling into thoughts of death and his mortality. But this time... My feelings about that had changed. To accept that dying isn't a big deal. It was just a purely just emotional mindset or perspective change. Paradigm shift is the right word. I mean, I remember being excited and writing like 2,400 words thinking I just solved death as a problem. And it wasn't until later that I realised I had thought of all these things years ago and it wasn't enough for me. So what he's saying is nothing had changed about his understanding of death, the concept of it. But what had changed were his feelings, his emotional reaction to it. It just wasn't upsetting for him anymore. And this got him thinking about the amygdala and he set out to see if his fear was changed in any other ways. So one day going hiking, I was like, all right, I know this cliff. I know that I actually once when I was like 16 leaned a little too close to that cliff and was like scared that I was going to fall off. And I was like, hey, what's going on? I don't want to fall off. I feel forms of aversion, like people are going to think I'm really dumb if I fall right now. But I didn't feel that sort of cascade of this is really bad idea, you're going to hurt yourself feeling. So it sounds like he had a rational interpretation of the situation. He could think about it in a kind of, what would you say, like an intellectual way? Yeah. And he doesn't say either that he was drawn to the edge of it or that it meant nothing to him. He said there was a normal aversion. This wouldn't be a great idea. I'd look a bit silly if I kind of just ended up falling. But that internal sense of terror or what he would perceive as terror wasn't there. And this lack of the physical component was consistent even when he thought he might actually truly be in danger. My car breaks down in Newark, New Jersey, which some parts are okay, but the part that I was in wasn't. Okay, so he's in a rough part of town and he meets a friend and they go for a walk while they wait for his car to be fixed. I'm a little bit on my toes because I see a bunch, a huge group of people and they all turn towards us and fan out across the sidewalk. And so I immediately think to myself, oh, I'm going to lose my phone, I guess. And he had been in situations like this before, but this time his reaction had been completely different. There was no feeling of like dropping into my body, looking around for the escape routes, just certain like threat, threat, threat detection moment. It was just sort of a casual like, oh, hey, a Sudoku puzzle, let's go. How do we fix this? I find that really fascinating. I imagine that fear inhibits a huge amount of my behaviour in day to day life. We avoid lots of things for that feeling of fear or even awkwardness. Lots of people avoid conversations because they just don't like the feeling in their body that is evoked by that. You might avoid going into a certain shop if you don't think you know what you're looking for. You know, the intimidation you get from going into new environments, that sensation, whether you're calling it fear or nervousness, anxiety, you know, in that kind of cluster of experiences does limit us in lots of very subtle but everyday ways. And in fact, he says, apart from a few memory problems, he's actually very happy with this new version of himself. It's changed the way that I've treated other people in a very positive way. I look back on the pre-surgery me with a lot of regret and a lot of pity, like, oh, wow, Jodie, you were really anxious and you didn't see it as anxious. You just saw it as logical. If he hadn't said about how he felt about his former self, I think I'd be reluctant to say this, but I feel a little envious of him. I mean, brain surgery is a massive deal. Chopping out parts of people's brains is not a thing that you would ever undertake lightly. But there is an appeal, right? The idea that you could dig into someone's brain and remove the bit, removing fear, it has a kind of Wizard of Oz quality. Well, this is kind of some people's literal wishes or desires for therapy. You know, they want to go in and they say, can you take away the part of me that's scared of this? Or can you take away the part of me that feels sad about that? There is this kind of wish to have that piece removed, whether it is a physical piece that could be taken out or just an experience or a memory that might be removed or erased. As a doctor, it's not uncommon to remove stuff from people's bodies, whether it's an infected appendix or a tumour, something like that. I'm familiar with that idea. As a therapist, you've gone and removed an emotion. Do you feel maybe a bit, not irrelevant, but like I feel like this is not the normal way you think about human emotions. Is this challenging to your view of the brain and the mind and things like this in some way? I think similar outcomes can be achieved without the brain surgery. But I think we might get to that a bit later. So Jodie's story is a fascinating one, but what does it mean? Is the amygdala really the home of fear? Let's get to the heart or the brain of the matter. There are other people who have almost complete amygdala damage who have no problems experiencing or perceiving fear. And in fact, there are certain cases where people are hyper vigilant to fear fall stimuli. This is Professor Lisa Feldman Barrett. Certainly when I was studying, we were talking about case studies like SM, a woman who due to a genetic disease called Erbach-Weif disease had calcified amygdalae. So they kind of atrophied, they stopped working and she seemed to lose what we would consider to be her fear response. And the psychologist took her to all sorts of strange situations. So they took her to an exotic pet shop and had her handle snakes and tarantulas. They took her to a haunted house, all these things which we presume should have frightened her. And she was just like, no, not so much. But actually it seems in real terms that it's not quite that clear cut. You know, she has a really painful experience at the dentist and then she never wants to go back to that, to not just that dentist, but any dentist. So what's interesting about her is that she just doesn't learn to experience fear in response to subtle things. So Professor Felbenbarrett thinks after all of this, that we might have the amygdala all wrong. The amygdala isn't the harbinger of fear or it doesn't, you know, it's not the home of fear. It just doesn't work like that. Okay. So I want your concentrating face because although the amygdala has this label of being the fear centre, Lisa is actually going to take us through a much more nuanced understanding of what the amygdala is all about. At this point, you know, it's really clear that the neurons in the amygdala are not for fear. They're not for emotion in any way. In fact, if I took your head and I stuck you in a brain scanner and I showed you images that you had never seen before, or maybe played you music that you had never heard before or speech that you'd never heard before. In fact, if I show you anything novel or uncertain, where you're uncertain of the meaning of the material, you will see increased engagement of amygdala neurons. So yes, the amygdala is important for processes like fear and emotion and anxiety. But the reason for that seems to be its role in signalling novelty. In general, what we could say is that the amygdala's function, if you could say that it had a single function, generally would be like a sentinel to sort of signal that you've encountered something which is novel or which is ambiguous. And so the rest of the brain has to marshal its resources to try to learn what that thing is so that you can basically predict its value to you and its meaning the next time you encounter it. So when Jodie sees the gang of people on the street, there's an ambiguous, it's novel, he doesn't know them, the amygdala rings the bell and goes, something's up here. Can the other bits of the brain try and figure out what's going on and make some assumptions? Is that what I'm understanding it? When you're going to your first day at school or your first day in a new job, there's that understanding that you're going to be in a novel environment with new people, new processes, new expectations. So the amygdala says, hey, everybody, wake up, make sure we're alert. We're going to have to learn lots of new things here. Whenever you're faced with something that is novel, that is ambiguous, or that your brain predicts might be harmful to you, your brain is going to release chemicals that will allow it to learn about the situation better. And some of those chemicals lead you to feel high arousal and unpleasant high arousal. You know, your heart will race, you'll sweat and it's unpleasant. So arousal in this context is a level of physiological alertness, kind of that energised feeling you get in your body. And Lisa says that this is also why the amygdala is important in anxiety. Your brain is always attempting to make sense of the sensory cues that it gets from the sensory surfaces of your body. And in our culture, the go-to way we make sense of high arousal and pleasant feelings is anxiety. Really what we're feeling is arousal that's unpleasant and then we make sense of it as anxiety. Can I see if I've understood it? So I'm in a new environment, a new day at school. I don't know I'm going to be beaten up. It's not necessarily dangerous, but it's the first day at a new school. And my brain raises my levels of physical and mental arousal. So I have adrenaline and all sorts of other hormones and chemicals released. I'm alert, I'm looking around, I'm more twitchy. And that is kind of tiring and not necessarily pleasant. My brain gets signals from my body that my heart is beating faster, that I'm breathing faster. And then my brain says, I will decide to interpret this as an emotion, probably anxiety, but you might interpret it as excitement. If you were really excited to go to a new school, you might interpret it totally differently. Yeah. So if for me, I grew up with lots of very anxious relatives who are always talking about their anxiety and their worry and their concern and so and so is a worrier, then the most relevant concept for me or my brain is anxiety. But if, for example, I grew up doing team sports, and I had a coach who was saying that feeling is being pumped, I'm ready to go. This is it, you know, this is the kind of battle cry, then I would interpret that my most available concept for those same physiological sensations is anticipation, excitement, preparation. And the concepts that I choose then are going to influence my performance. If I feel anxious, often the associated behavioural components of anxiety are retreat, fearfulness, worry, self-consciousness, that's going to distract me from my performance. Yet, if I think, oh, actually, I'm capable, I'm ready to go, that's going to have a completely different effect on how I perform. I really like that. That's really cool. And so we can start to reframe what's happening in our bodies in the way that's much more helpful for us. Many people experience test anxiety, and they experience test anxiety to such an extent that it doesn't just keep them from passing a course, they sometimes will drop out of school, drop out of university. And a university degree has a huge impact on someone's future earning potential for the rest of their life. Now, you can train people to, instead of making sense of their increased arousal when they're facing a test, instead of making sense of it as anxiety, you can train them to make sense of it as determination, for example. Now I want to make the point that their arousal isn't going down, so their amygdala activity isn't diminishing. And you wouldn't want to diminish amygdala activity in that case, because even though the arousal is unpleasant, you have to remember that the amygdala's function, to some extent, is to mobilize resources to allow you to learn better, to perform better. So in this case, you really wouldn't want to reduce amygdala activity, but you would want to change how a brain makes sense of that activity. And in fact, there's really good research to show that if you do, the arousal doesn't go down, but their performance goes up and they pass tests, and that has a really big impact on their future earning potential. I just feel like this is so personally useful. How do you go about reframing arousal as something more positive? Is it a thing where I can literally go, the next time I'm giving a talk or the next time I'm taking an exam, I can go, nope, come on, your fast heart rate, your breathing, your sweaty palms, that's all good, that's all okay, reframe it and go into the exam, or do I need to do weeks of work with a therapist to try and get there? Well, anecdotally, that's kind of what I've done. After I read Lisa's research, I thought I would give this a go. And what I've found really helpful is to literally say to myself, when I get those physiological signs, oh, this is just a sign that my body is preparing me. Thank you, body, let's go. So to not over-interpret it, to not go into a spiral of, am I anxious or worried? Do I need to hide how nervous I am? Just to say, well, this is normal. This is my body working perfectly well, preparing me for this new thing that I'm about to do. And it just takes the edge off quite a bit and allows you to get on with it. I think that that arousal doesn't have to be fear. Instead, if you understand it as uncertainty, that will dictate your choices that you'll make in terms of your behavior a little differently. And that can have an impact in your relationships, that can have an impact in your education. It's even important for maintaining a democracy. It turns out there are all kinds of complicated ways that understanding how your brain works can allow you to live a better life. So the amygdala isn't just about fear. And it has this much more, I think, much more interesting role in our emotional experiences, in this signaling of novelty, ambiguity, and uncertainty. And I think that reframing for a lot of people, not everyone, of course, but for a lot of people who do, I think, interpret uncertainty as anxiety and terror, would just give them a little bit more breathing space and give them the opportunity, I think, to have a bit more faith in themselves. Because often people think that confidence is everything. I should feel confident all the time. And if I don't feel confident, then it's a sign of some sort of failing. You know, maybe I have imposter syndrome. Maybe it's not imposter syndrome. Maybe you are just rightly unsure or uncertain about this thing that you're about to do. And that's fine. Okay, if all this is stressing you out a little bit, then take a deep breath, relax, and let's meet our next guest. So a lot of people ask me how I got involved in this research. And back when I was in graduate school, I developed a sports injury. And I went to see a physical therapist, and they told me that I needed to stretch. This is Dr. Sarah Lazar, a neuroscientist at Massachusetts General Hospital. As I was leaving the physical therapist's office, I happened to notice an ad for a vigorous yoga class. I thought this would be a great way to just stretch and, you know, stay in shape. This is 25 years ago now. At that point, yoga was a dirty word. You know, it was equated with healing crystals and tinfoil hats. It was just not well loved. But I went purely as a form of physical therapy. And I was very skeptical when the teacher made all sorts of claims about, oh, this pose will do this for you. And this pose will do that for you. I was like, yeah, yeah, yeah, I'm here to stretch. But it started having an impact on me. And I had been a runner for many, many years. So I knew it wasn't just exercise. I knew it wasn't just stretching. There was something different about yoga. And so I decided when I finished my PhD to switch. And I've been doing research on yoga meditation ever since. Sarah found that after yoga, she was less irritable, more forgiving. And when she looked into the literature, she couldn't find anything to back this up. So she began to look into it. And that meant looking all over the brain. But some areas seem to be more important than others. So the amygdala is involved in a lot of emotions. It's also a part of the brain that regulates stress hormones. And we know that yoga and meditation are really good for dealing with stress. So definitely the amygdala was a region of interest for us. And it's probably been one of the most well-studied brain regions in the context of meditation. So to find out if the meditation affected the amygdala, Sarah ran a study. So one of our first studies, we looked at people's brains before and after an eight-week mindfulness-based stress reduction program versus the controls we just scanned eight weeks apart. And they didn't do anything in between those eight weeks. And what we found was that the amygdala got smaller and that the change in the amygdala correlated with the changes in stress. So the more stress reduction people reported, the smaller their amygdala became. Something was going on, which meant that people in the group that meditated had a smaller amygdala at the end of the sessions. And this was really cool because often before that, there was a lot of research showing that people reported being less stressed after going through these programs. But the critics were always saying, well, you know, two months have passed. And so whatever was stressing them out at the beginning was no longer stressing them out. And so this really demonstrated that no, that there was a neurobiological reason why they were feeling less stress. The amygdala was actually being rewired and that that was what was causing them to feel less stress. This is one of the components of what we call neuroplasticity. And a very famous example is that London taxi drivers who spend three years doing the knowledge, driving around the many, many streets of London on a very complex layout, you know, we don't have the grid system, have bigger hippocampi. And that's the part of the brain that is most associated with memory and organizing spatial information. And so it's the stress of learning, the good stress of learning that causes the hippocampus to expand and grow to accommodate all of this new information and all of these new processes. So you can literally reshape your brain. I mean, your brain is always reshaping in response to experience, but you can direct that reshaping by where you direct your attention and the things that you put your mind to. So since then, we've done two more studies where we compared meditation to exercise and another study where we compared meditation to yoga and to a talk therapy program. And in all three studies, what we're finding is this correlation between stress and the amygdala size is only in the meditation group. So it's not in the yoga group and it's not in the exercise group. And so although both of those are good for reducing stress, they're doing it to some other mechanisms. They're not doing it through the amygdala. So it really seems like this change in the amygdala really is specific to meditation. So if you meditate, you may be actively changing your brain, not just during the meditation itself and maybe immediately afterwards, but actually rewiring it for everyday life. Showing that the actual brain structure changes and the wiring is changing, it really has this implication that it's not just that you're calming down while you're meditating, that there really will be spillover effects throughout the rest of your day. There's been a huge amount of hype around meditation and mindfulness and a lot of mission creep. So a lot of people, I think, started in Silicon Valley, didn't it? When all the big tech heads of the tech companies were deciding that meditation was going to make them more efficient and proficient and calm and great leaders. And there's been a lot of spillover. And I think it is important to distinguish the difference between the, I guess, the evidence base and the hype. I think what happened, and I saw this myself, was that, you know, because I got a lot of media interviews, right? And so often the way the stories were written, the story starts off with someone who has had a lot of medical problems and they go to the doctors, nothing works. They turn to meditation, all of their problems have been solved. And so what we know is that actually the changes in the brain are actually pretty modest. Not everyone has the brain changes, you know, and that results very tremendously. And so some people with meditation will have really profound life-changing experiences with meditation, but a lot of people don't. And so I think it did get overhyped, right? And that there was this idea that, oh yeah, it didn't matter what you had, just start meditating, all of your, you know, ills will be cured. And it's really clear that it's not that. It's that there's a handful of people that's true. There's also people who have absolutely no benefit and most people it's somewhere in between, that you get some modest benefit, you know, with some practice. So there's definitely benefits for most people, but it's not the miracle cure. That just seems like such a terrible standard to hold meditation to. I think it speaks to how desperate we are to feel better or to have something that we can do that will make us feel better. I think it speaks to the way that people feel tired and they feel sad and they feel put upon and they feel powerless to do very much about it. So I think when something new comes in, especially if it's something new that it also has an evidence base, then you think, well, maybe this is it. This is the thing that I've been waiting for. This is the thing that's going to turn life around and make me feel like I can manage. I think there are a lot of people that just don't feel like they're managing very well. So is there something I can do if I wanted to start meditating now? Where would I begin? Can you give me a thing to do or is it more complicated? Do you think you need it? I think that's the thing. It's do you think you need it? And then it's worth knowing that there are different ways to meditate. So for some people, it's sitting still and focusing on breath. For some people, it's going for a walk and focusing on sensation. It's worth knowing there's more than one way to meditate or be mindful if that's what you want. So try a few, find what works for you. Give it a go for a bit because the brain needs a little bit of practice for something to become a habit. But if you try and you really, really, really don't like it, then it might just not be for you. And there might be another better way for you to get some of those benefits elsewhere. That's so interesting. I thought you're going to tell me to breathe in for five and out for seven. I mean, you can if you want to. I think this reformulation or this reimagining of what the amygdala is all about is powerful in a very subtle way, because what it means is that in those several dozen a day situations where you might feel a slight pang of anxiety, like, oh, someone's calling me, do I pick up the phone or do I just text them? Or, oh, I need to ask somebody for a favour. All of these little moments that we might avoid or delay or somehow make a meal of. If we can reformulate that experience, those feelings as not a sign that anything is wrong, not a sign that we're incapable, but a sign that this is novel or this is just demanding a little bit more energy, it's a bit ambiguous, you don't know what the other person is going to say, but you can still go ahead and do it. Then I think you begin to have more faith in yourself. That builds confidence, confidence breeds more confidence and more people feel more able to do everyday things. It's so good. You're so clever and wise. It's so great. I get to sit in a booth with Kimberley Wilson and she tells me how to live and it's great and I always feel better. On that note, that is it for this episode. Hopefully you have come away like me with a more nuanced understanding of your amygdala and also how to approach your life and how to make better emotions in your head. Hopefully you're at peace with how complicated our brains are. Thank you so much to our guests, Sarah Lazar, Lisa Feldman Barrett and Jodie Smith. And that's it for this episode and sadly the end of the series. Thank you so much for listening. We hope you've enjoyed it and if you have, please don't forget to give us a rating and a review. Tell all your friends, call your auntie, your cousins, make a banner and with a bit of luck, we'll be back for another series. Thank you so much for listening. We do hope you've enjoyed it. We hope you've learned something from it. It's changed us and I hope it's changed you. Thank you so much to our amazing producers. We literally could not do it without them. Georgia Mills and James Tyndale. The associate producer was Leonie Thomas and the executive producer was Bob Nicholson. I'm Zan van Tulleken, she's Kimberly Wilson and this was a Whistle Down production for BBC Radio 4. Since the war began, my inbox has been flooded. People from Ukraine, Russia and Britain are getting in touch with me. They're telling me about a very different battle, but one that's also having real consequences for the people caught up in it. I'm Marianna Spring and in this new podcast for Radio 4, War on Truth, I'll be reporting on the extraordinary information war being waged over Ukraine and hearing from the ordinary people sucked into it. This blatant denial of reality is being waged by trolls, state media, influencers, online and beyond. From BBC Radio 4, War on Truth. Subscribe now on BBC Sounds.