Challenges in Replicating Findings in Literature and Finding Objective Measures of Emotions Transcript: Speaker 1 And in the course of doing the research that I was assigned to do at the outset of my PhD training, I attempted to replicate some existing findings in literature. I tried eight experiments that I tried to replicate and wasn’t able to do so. My first reaction was, okay, so I’m probably not cut out to be a scientist, obviously. But then, you know, when I calmed down and I kind of looked at my findings, I realized, well, the one thing that was replicating over and over and over again was the fact that the emotion Measures were not performing the way that they should have, you know, that they seem to be problematic. And so I just assumed I was using the wrong measures and that what I really had to do was find objective measures of anger, sadness, fear, disgust, and so on, and that it would be super easy To do this because, you know, everybody knows that there are, you know, each of these emotions has a universal facial expression that everyone around the world can make and recognize. But then, soon I found, well, that’s actually not true. When you look at the scientific evidence, there’s really no evidence that scowls are universally made in anger and that pouts are universally made in sadness. And that even smiles are universally made in happiness. (Time 0:04:03)
The Search for Objective Measures of Emotions Transcript: Speaker 1 And so I just assumed I was using the wrong measures and that what I really had to do was find objective measures of anger, sadness, fear, disgust, and so on, and that it would be super easy To do this because, you know, everybody knows that there are, you know, each of these emotions has a universal facial expression that everyone around the world can make and recognize. But then, soon I found, well, that’s actually not true. When you look at the scientific evidence, there’s really no evidence that scowls are universally made in anger and that pouts are universally made in sadness. And that even smiles are universally made in happiness. And they’re certainly not universal, we recognized around the world. So I thought, okay, well, you know, maybe Darwin was just wrong about that one thing. So, but everybody knows, you know, that each emotion has its own pattern of physical response. William James said so. But then when I scratched the surface of that black hole, I realized very quickly, well, actually William James didn’t say that. William James being one of the fathers of American psychology. In fact, he said the opposite. And in fact, the evidence doesn’t really bear out the idea that we, that each emotion has a single physical fingerprint in the body. And so basically, for me, it’s just been this long odyssey of trying to understand the biological basis of emotion. (Time 0:04:48)
The Puzzle of Understanding Emotions with No Single Expression or Fingerprint Transcript: Speaker 1 Yes, it does. And instead, what you’re left with is an incredibly interesting puzzle that if there’s no single facial expression that people make when they’re angry or sad or afraid and so on, if There’s no single autonomic nervous system fingerprint, so it’s not the case that when you’re angry, your heart is doing one always doing the same thing, your breathing rate always Changes in the same way and so on and so forth. If it’s the case that the pattern of brain activity in different instances of anger, let’s say, looks different, then how is it that all these different varieties of experience of anger, We know as anger and how is it that we’re able to look at each other’s faces and bodies and listen to each other’s voices. And in the blink of an eye, it feels to us as if we’re reading people’s emotions the way we read the way we read words on a page. So this is a really interesting puzzle. And sometimes in science, as you know, when you fail to replicate something or you fail to support a hypothesis, what is laid before you is the opportunity for great scientific discovery. Speaker 2 I’m looking forward to talking about the new theory that you have and I guess your coworkers have come up with. But we need to back up to the basics and just ask, you know, what is the, what you call in your book, the classical theory of emotion. Speaker 1 Well, the classical view of emotion, I think, will be familiar to many of your listeners. It’s the idea that in the brains of all of us, we have buried deep in the animalistic parts of our highly evolved brains. We have emotion circuits, one for anger, one for fear, one for sadness, one for disgust, and for happiness, and so on and so forth. (Time 0:07:11)
Metaanálisis demuestran que emociones no están localizadas Transcript: Speaker 1 So originally, scientists thought that perhaps there was a single region of the brain that was most important for particular emotions. So they would try to localize the circuitry for fear, for example, in a brain region called the amygdala or the circuitry for disgust in a brain region called the insula. And so one of the first things we learned is that emotions can’t be localized to particular brain regions. So we have done a number of our own experiments in this regard, but we’ve also done what are called meta-analyses, which is summaries of hundreds and hundreds and hundreds of studies, Brain imaging studies, where we combine them statistically and this gives us a lot of power to search for the evidence to test these hypotheses, these ideas. So when it became clear that emotions couldn’t be localized to particular brain regions, then we tested the hypothesis. Many people had the hypothesis, well, maybe an emotion can be localized to a network. So there’d be one network for anger and one network for sadness and so on. And again, we did a number of studies and we also did meta-analyses and showed pretty convincingly that there are no individual networks for emotion either. (Time 0:16:28)
cerebro emociones localización neurociencia
cerebro emociones localización neurociencia
No hay lugares en el cerebro que sistemáticamente se asocien a emociones específicas. Transcript: Speaker 1 So originally, scientists thought that perhaps there was a single region of the brain that was most important for particular emotions. So they would try to localize the circuitry for fear, for example, in a brain region called the amygdala or the circuitry for disgust in a brain region called the insula. And so one of the first things we learned is that emotions can’t be localized to particular brain regions. So we have done a number of our own experiments in this regard, but we’ve also done what are called meta-analyses, which is summaries of hundreds and hundreds and hundreds of studies, Brain imaging studies, where we combine them statistically and this gives us a lot of power to search for the evidence to test these hypotheses, these ideas. So when it became clear that emotions couldn’t be localized to particular brain regions, then we tested the hypothesis. Many people had the hypothesis, well, maybe an emotion can be localized to a network. So there’d be one network for anger and one network for sadness and so on. And again, we did a number of studies and we also did meta-analyses and showed pretty convincingly that there are no individual networks for emotion either. Something now that people researchers do is they’ll look for a pattern of activity that’s distributed across the whole brain to try and find the pattern that summarizes what an emotion Like anger looks like in the brain. And what’s really interesting is what we see in these studies is what we see elsewhere as well, which is that you can find a pattern across the brain, the entire brain, which in a given Study distinguishes anger from sadness from fear. But when you look at another study, which also uses a whole brain pattern, it can find patterns to distinguish anger and sadness and fear. The patterns aren’t the same. So there’s a lot of, again, variability is the norm. (Time 0:16:28)
cerebro emociones evidencia
Identifying Anger through Brain Activity Patterns in Neuroscience • Patterns of brain activity can identify emotions like anger. • A pattern classifier can diagnose emotions with almost 100% accuracy. • The classifier works by finding which pattern of brain activity is closest to known emotional patterns. • Understanding brain patterns is similar to how Darwin understood species. Transcript: Speaker 1 And what we found in our simulation was that we could identify anger. So we could look at somebody’s activity pattern in their brain, and we could, with almost 100% accuracy, use our pattern classifier, our pattern to diagnose whether or not somebody Was feeling angry in that moment, yet not a single voxel was shared in common between that person’s pattern of activity in their brain and the pattern itself. So basically, the way that these things work is the mathematics is basically asking, when you look at someone’s pattern of brain activity, you’re asking which pattern is it closest To? Is it closer to the anger pattern in that study or the sadness pattern in that study? And so it’s just more like a similarity judgment. And the really cool thing here is that this way of understanding these patterns is very much in line with how Darwin understood a species. So before Darwin came along, natural historians, which is what biologists used to be called, really (Time 0:20:32)
Las emociones son categorías biológicas en donde la diversidad es la norma. Transcript: Speaker 1 And the really cool thing here is that this way of understanding these patterns is very much in line with how Darwin understood a species. So before Darwin came along, natural historians, which is what biologists used to be called, really they understood a species of animal to be kind of a classical category where, let’s Say a cockerspanial, there was a perfect ideal cockerspanial with the perfect ear length and the perfect tail length and the perfect nose length and the perfect thickness of coat and Color and so on. And everything around that was thought to be error mistakes. So all the variability in the individual cockerspanials that you could see were thought to be error because there was one platonic perfect form of a cockerspanial that God made. I mean, that was the original idea. And Darwin, so it’s like the way I think of it as like the dog show version of a species, right? So there’s like a perfect dog. And Darwin came along and said, wait a minute, you know, this variation that we see in nose length and ear length and tail length and so on is really meaningful. And it’s meaningful in relation to the environment. That is, without this variability, the environment can’t select which individuals are going to live and which individuals are going to not survive. And without this variability, the species itself would die off very quickly. So variation is really important to the survival of the species because you want a species, a group of animals that’s really robust to changes in the environment. And that’s what variability buys you. And so, you know, Darwin’s at the core of all of Darwin’s insights, the most important insight that he shared in on the origin of species, his most famous book, is the idea that a biological Category like a species is actually a highly variable category. In fact, you’d call it a conceptual category in the sense that the category, the instances, the individuals in the category are highly variable. No individual looks exactly the same as any other. But yet you have the ideal form, which is just kind of like the symbol or the stereotype of the category. And it doesn’t even have to exist in nature. It’s just a good symbol, symbolic representation of the category. And so to some extent, that’s the way we understand emotions, exactly the way that Darwin understood a species, that each emotion category, anger, sadness, fear, and so on, is a highly Variable set of instances that are tied specifically to the situation that you’re in. Your brain is able to not make one anger, but a whole variety of angers, each one tailored to the situation that you’re in. And so from a brain imaging standpoint, what this shows, how this, what this looks like, is that you see a lot of variability, but you also within an individual experiment, you can find A summary pattern that summarizes all this variability. Even if nobody actually in their brain, nobody has a pattern, which is identical to this summary. The summary still works pretty well within a given experiment. Unfortunately, the pattern doesn’t generalize across experiments because of all this variability. (Time 0:21:27)
categoría emociones especie variabilidad
Variability and Degeneracy in Biology • Biologists use the term ‘degeneracy’ to describe the phenomenon of multiple mechanisms producing the same outcome. • Degeneracy is not redundancy, but rather the existence of multiple ways to achieve the same result. Transcript: Speaker 2 This variability, would you say, ties to this other idea that you talk a lot about in your book on degeneracy? Yes. Speaker 1 So one of the things I learned, as I said, I read pretty widely. And one of the things I learned is that biologists have this fantastic idea that they’ve, it’s not just an idea, it’s actually a real phenomenon that they’ve discovered. Unfortunately, they gave it a really horrible name. You know, degeneracy is the name of the phenomenon. And degeneracy means basically there’s more than one way to skin a cat. The idea is that there’s more than one set of mechanisms that can produce the exact same outcome. So it’s not redundancy. It’s actually, you know, think of it, for example, on a map as multiple paths that you (Time 0:25:15)
Understanding the Similarities in Categories: A Cognitive Science Perspective Transcript: Speaker 1 You’re able to look at somebody else and even though sometimes they might be laughing, sometimes crying, sometimes in a stony silence that you will understand in the right context, All of those are sadness. Experience that person is sad during all of these expressions. How could that be possible? And so I turned to the cognitive science literature, for example, on concepts and categories. And I learned there’s a whole history of the study of concepts and categories. So a category is a group of things that are not necessarily that look the same or that sound the same, but are similar for some purpose or some function. So we’re used to thinking of categories as things that always are exactly identical. They’re similar to each other in their physical properties, but actually a category is a set of things which are similar to one another in their functional properties. So for example, you can have a category of things that protect you from the rain, for example. And lots of things can protect you from the rain that don’t look the same, don’t sound the same, don’t feel the same, don’t have the same structure. And it turns out that we don’t have categories stored in our brains. When someone asks us about a category, we kind of conjure up an instance of that category. (Time 0:30:28)
Understanding the brain as a set of networks Transcript: Speaker 1 Researchers tried to do that for a long time, but it’s become very, very clear that the billions of neurons that are networked together that to make up your brain can be understood as A set of networks, smaller networks. These networks are not independent of one another, first of all. So it’s not like the networks in your that make up your big brain are like Lego blocks which fit together that they’re independent of one another. They actually share neurons with one another. So a better example would be like Pittsburgh airport, for example, has a lot of different terminals, but all the terminals share a common hub and it turns out in your brain, your brain Has a bunch of networks, but they overlap. They share these hubs, basically, or these very connected regions of the brain and each network performs more than one function. So you can think about these networks a little bit like ingredients in your kitchen. So just in the same way that if you look in most American kitchens, you’ll find flour and water and salt. And you can make a lot of different recipes with flour and water and salt. And you can even make some recipes that are not even food like recipes, like you can make glue out of flour and water and salt. (Time 0:35:23)
Brain networks perform multiple functions like ingredients in a recipe Transcript: Speaker 1 They share these hubs, basically, or these very connected regions of the brain and each network performs more than one function. So you can think about these networks a little bit like ingredients in your kitchen. So just in the same way that if you look in most American kitchens, you’ll find flour and water and salt. And you can make a lot of different recipes with flour and water and salt. And you can even make some recipes that are not even food like recipes, like you can make glue out of flour and water and salt. And so the same networks that are involved in making a motion also make thoughts and memories and perceptions. Even when you look at the visual system, for example, and you look at the primary visual cortex, which is like the earliest part of the visual system when information from your retina Makes it so the retina in your eye makes it all the way to your brain. And it goes through a series of sub-cortical regions up to the cerebral cortex. The first place that it arrives is this place called primary visual cortex. But those neurons don’t just code information about vision. They also code information about hearing and about touch and so on. So even the sensory regions of our brains are not, they don’t just have one function. (Time 0:36:12)
The Importance of Metabolic Efficiency in Electrical Signal Processing Transcript: Speaker 1 And so these are the exact same networks, right? We’re not talking about different parts of the network. We’re talking about the exact same networks. So that was also, I think, one piece of the puzzle. And the final piece of the puzzle for me came when I realized that after reading a lot of anatomy, and then I started to work with some engineers who got me really interested in the physiology And physics of electrical signal processing because the way that neurons communicate with one another is partially electrical. And so when I started to read this literature, I realized a couple of really important things. One is that all systems in your body, including in your brain, have to be metabolically efficient. This is something that’s really, really important to the normal functioning of your nervous system, actually, of your body in general. But in particular to your nervous system because your brain takes up about 20% of your metabolic budget. And so that’s, it’s a really expensive organ. And so it has to be really, really efficient. (Time 0:38:09)
The Brain’s Efficient System: Prediction vs Reaction Transcript: Speaker 1 And so that’s, it’s a really expensive organ. And so it has to be really, really efficient. The other thing which is really interesting is that the most efficient way to run a system is not to have that system lie around dormant, doing nothing, and then be stimulated and then React. That’s actually a highly inefficient system. The most efficient systems actually are predicting. They’re kind of like running a model, kind of predicting what’s going to happen, and then using input to correct those predictions. So this is very counterintuitive because there’s nothing in our experience of ourselves or the world that would ever lead us to this hypothesis. However, when you look at the structure of the brain and how neurons are connected to each other, when you look at the physiology of how things work, when you look at the electrical signal Processing properties, what you see really clearly is that the brain is organized to predict not to react. So it feels to us, when we’re happy or sad or angry, like we’re just reacting to things that are happening in the world. (Time 0:39:19)
Ejemplo de cómo el cerebro funciona en base a predicciones. Transcript: Speaker 1 If I ask you, for example, right now to keep your eyes open, maybe listeners will do this too, keep your eyes open. And in your mind’s eye, try to conjure the image of a green granny Smith apple. Absolutely. And if I ask you to imagine the crunch of the apple when you bite into it, can you sort of hear that? And if I ask you to imagine the taste of that, you know, that really tart taste of a granny Smith apple, could you kind of imagine the taste of the apple? So in each of these cases, I’m asking you to imagine these things. And what your brain is doing in these instances is that some parts of the brain are causing the neurons in your visual cortex, in your auditory cortex, in the parts of the brain that are Important for representing taste to change their firing in the absence of an apple. So basically, that’s what your brain is doing when it’s making a prediction. It’s anticipating what the sensory changes are going to be in the next moment and preparing you to experience those. And then when the, in fact, if I, so if I brought out a granny Smith apple and I showed it to you and you predicted it well, then nothing about that apple, no information about that apple Would actually make it in very much further into your brain because the neurons are already firing in a way to capture it. Your brain only takes in information that it doesn’t predict. And we have a very fancy name for this in, in psychology, we call it learning. That’s what learning it. And this is a very metabolically efficient way to run a brain. (Time 0:43:35)
aprendizaje cerebro definición ejemplo predicción
Ejemplo para ilustrar cómo la predicción opera en el cerebro. Transcript: Speaker 1 And in your mind’s eye, try to conjure the image of a green granny Smith apple. Absolutely. And if I ask you to imagine the crunch of the apple when you bite into it, can you sort of hear that? And if I ask you to imagine the taste of that, you know, that really tart taste of a granny Smith apple, could you kind of imagine the taste of the apple? So in each of these cases, I’m asking you to imagine these things. And what your brain is doing in these instances is that some parts of the brain are causing the neurons in your visual cortex, in your auditory cortex, in the parts of the brain that are Important for representing taste to change their firing in the absence of an apple. So basically, that’s what your brain is doing when it’s making a prediction. It’s anticipating what the sensory changes are going to be in the next moment and preparing you to experience those. And then when the, in fact, if I, so if I brought out a granny Smith apple and I showed it to you and you predicted it well, then nothing about that apple, no information about that apple Would actually make it in very much further into your brain because the neurons are already firing in a way to capture it. Your brain only takes in information that it doesn’t predict. And we have a very fancy name for this in, in psychology, we call it learning. That’s what learning it. And this is a very metabolically efficient way to run a brain. (Time 0:43:44)
cerebro ejemplo predicción
How the Brain Makes Predictions About Our Emotions Transcript: Speaker 1 That’s what learning it. And this is a very metabolically efficient way to run a brain. So what does this have to do with emotion? Well, it turns out that just in the same way that your brain is making predictions about what you will see and what you will hear and what you will taste and so on, it’s also making predictions About what you will feel in your body. So your brain isn’t just, its job isn’t just to create the, your ability to see and hear and taste it. It’s also controlling the systems inside your body. You have a system for your heart and your blood, your cardiovascular system. You have a system for your lungs and so that you can breathe. This is your respiratory system. You have a system for water, a system for salt, a system, your immune system, a system for your metabolism. You many, many, many systems in your body. And your brain has to predictably control those systems. And it has to be done predictably. Your brain has to predict what your body needs and then move the resources around so that your body gets what it needs before those needs arise. Otherwise you’ll be sick or you’ll hurt yourself. (Time 0:45:19)
Supporting Brain Science Podcast and Understanding Newborn Emotions Transcript: Speaker 2 I want to take a moment to thank everyone who has helped support my work, both financially and by sharing it with others. While I’m at it, I will mention that how emotions are made is available from audible.com and I will include a link to audible in the show notes. If you’d like to learn more about how you can support this show, please go to brainsciencepodcast.com forward slash donations to find the option that’s best for you. Somebody is probably going to object that it certainly doesn’t, a no pun intended, feel like that’s what’s happening. I mean, it really feels like emotions. I mean, how do babies appear to have emotions from the very beginning? Speaker 1 Well, they don’t have emotions though. So one of the things I talk about in the book is I cover the research showing pretty convincingly that newborn babies, they have these feelings of pleasure and distress, a feeling worked Up and feeling calm, what scientists call affect. (Time 0:48:42)
Newborns Have Affect, But Not Adult-Like Emotions Transcript: Speaker 1 Well, they don’t have emotions though. So one of the things I talk about in the book is I cover the research showing pretty convincingly that newborn babies, they have these feelings of pleasure and distress, a feeling worked Up and feeling calm, what scientists call affect. But they, when a parent looks at an infant and experiences that infant as angry or as sad or as afraid or as happy and so on. The parent is using their own predictions, their own conceptual system in their own brain to make sense of that baby’s affect, to make sense of that baby’s distress or so the parent is Guessing at the mental state of the baby. But babies are, they’re not born with brains that are like miniature adult brains. They’re born with brains that are equipped to wire themselves to the physical and social surroundings that they grow in. So they don’t, they have the capacity to feel pleasure and pain. They have the capacity to be worked up and agitated or calm, but they don’t have the capacity to experience adult-like emotions until they have learned emotion concepts. And this is something that I explain in my book. Right. Speaker 2 In the book, you say that words are the secret ingredient. Speaker 1 And they are because words allow us to learn how instances that look different, that sound different and that feel different actually can be part of the same category. And words actually serve this purpose in infants as young as three months old. (Time 0:49:31)
How Babies Learn to Categorize Objects and Emotions with Words Transcript: Speaker 1 So the baby in that instance is learning that all of these things which look different and sound different and they feel different, the touch of them is different, are actually part Of the same category. That’s just like what an emotion category is, where faces are different and bodies are different and the feeling is different, but yet it’s all the same emotion. How could that be? Well, a word is part of the answer here. Similarly, with babies, you can take two objects which look exactly the same, found exactly the same, you know, have exactly the same texture, but you give them different words, you Name them, label them with different words and the babies will assume that these are very different objects, they do very different things even though their physical properties are Identical. (Time 0:53:00)
The Theory of Constructed Emotions and Its Implications Transcript: Speaker 2 In fact, the reason I invited Lisa Barrett on the show was that the theory of constructed emotions has the potential to change the way we see ourselves. First, we aren’t passive receivers of experience. We actively participate in determining what we see, even though this happens outside of our awareness. Emotions are constructed in the same manner, which means we construct our emotional experiences and our perception of other people’s emotions. She goes into a lot more detail in the book, but the point is that the theory of constructed emotions empowers us to find ways to change when needed. The principle of brain plasticity applies here also. The world around you wires your brain. Do you surround yourself with anger and hate? Or do you spend time with people that nurture positive emotions? Obviously, abandoning the classical view of emotions has great implications for our justice system since it is based on the classical theory. Dr. Barrett’s book has chapters about justice and about how the theory could impact our attitudes about health. But overall, abandoning the classical view is quite empowering because we no longer have to see ourselves as victims of an internal struggle between our emotions and reason. (Time 1:23:33)