The Neuroscience of Empathy | Thomas Lewis | Talks at Google

Well, thank you all for coming, and welcome to another Authors at Google event. We are very fortunate to have Dr. Thomas Lewis here with us today. Dr. Lewis is an assistant clinical professor in the Department of Psychiatry at the UCSF School of Medicine and professor at the Fromm Institute at usf. He has lectured on a broad range of topics related to psychopharmacology and psychobiology. Among the courses he has taught at UCSF are the neuroscience and poetry of emotional experience and the neuroscience of morality. He has even consulted with major motion picture productions and the California Shakespeare Festival on the science of emotion and its role in the dramatic arts. He is the author of A General Theory of Love, where in his preface, he writes. Now, he wrote this, this book as it elucidates the shaping power of parental devotion, the biological reality of romance, the healing force of communal connection argues for love. Turn the page and the arrow is loosed. The heart it seeks is your own. He is here today to talk about his recent work on the neuroscience of empathy. Please welcome Dr. Lewis.

Thanks very much. How do I get the little preview thing off there? Does anybody know? There we go. Okay. Well, thanks. I'm very happy to be part of your Google Author series, and I'm very happy to come here as a writer, but more importantly, as a Google shareholder. Having been a physician and a writer and a Google shareholder, I can tell you that the last of those three is vastly more profitable than either of the other ones. So keep up the good work, if only for my sake. So I am Tom Lewis. I'm one of the authors of A General Theory of love along with Dr. Fari Amini and Dr. Richard Lannan. And today we'll be talking about the neuroscience of empathy. And I'll be showing you some research into that area, most of which post dates, I think, 2000. So it's all pretty recent stuff. So let me just tell you the landscape of what we'll be talking about today. First, we'll start off talking about evolution a little bit, and we'll talk about where the brain comes from in the first place, which helps us understand why empathy exists at all. Then we'll turn our attention to the brain and we'll look at three different mechanisms of empathy and the brain locations. They arise from a mechanism of modeling other people's behavior, of projection of self image and adjusting the balance between self and other. So that's the map of where we're headed today. If anything I say starts to not make sense, let me know so that I can correct it. And then we'll have some time at the end for more general questions. One of the things I noticed when I was making up this slide is that for those whose minds run to such things, the map is a virtual anagram for the word empath. And if we look at the word. Actually, I like looking at word origins. It may tell us something about the phenomenon empathy. The word comes from am, the root meaning in, and then path, which means feeling or sorrow or suffering. The same kind of word that shows up nowadays in pathology or pathetic. So that empathy as a word means into the sorrow or into the suffering feeling of somebody else. And we'll look at how that. How our brain allows us to do that, how it allows us to feel the suffering and distress of other people. So first, just a word about evolution and the brain. This is the brain that we have now, looking at it from the side. And if we look at an mri, this is a sagittal section, sagittal, from the Latin word meaning arrow, just like Sagittarius the archer. So this is if an arrow just split your head in two and then you looked at it from the side, that's a sagittal section. So where did this come from? And why does it look the way that it does? I'll show you a brief model that may be mildly simplistic, but it'll serve our needs. And the planet itself here is about 4 billion years old. And life on the planet shows up about a billion years into the history of the planet in the study of empathy, Then nothing else happens for a long time, right up until almost the present day. So if we go back, say, to 300 million years ago, the Earth looked like this. And animals like this were on the planet, for instance, at that time, almost unchanged from the way that we would find them in the oceans today. And essentially what we can see is that this animal is a hollow tube ringed with teeth. There really is not that much of this animal except eating and then things passing out the other end. Now, eventually, these large fish grew legs and they crawled out onto the land. There's also a very ancient animal here. And then about 265 million years ago, this would be the age of the reptiles or the dinosaurs, so that animals like this, giant lizards, walked the Earth, some of them. This is a Komodo dragon that you can still find on the Earth today. Giant lizard. And then some of these reptiles became very, very large. And I'll show you just a little bit about what life was like at that. So there was not a lot of empathy to go around on the planet at that time, for a good reason, was that reptiles do not have empathy, as we'll see, because they don't need it. Then about 200 million years ago, Earth looked like this and mammals evolved, split off from the reptilian line. At that time. They still look like this little tree, living shrews, kind of like a tiny mouse really, not much to them. And then about 65 million years ago, probably the most important thing in the development of empathy happened, which was an asteroid struck the planet. My little animation doesn't do it justice. So see what it looks like from this view, that A gigantic asteroid, 1100ft across, struck the planet with unimaginable force near the Yucatan Peninsula. The main problem was not this big ring of fire and destruction per se, which incinerated everything in its path, but the debris which was kicked up into space. And then inevitably this massive amount of debris was recaptured by the Earth's gravitational field and came back to the planet in the form of innumerable flaming meteors. Essentially what happened is that the entire surface of the planet was carpet bombed, as we would say now, and incinerated. 90% of the biomass of the planet at that time was incinerated. Two thirds of the species on the planet at that time went extinct. And after the fires was really the first nuclear winter, say that the planet had seen. The sky was so dark with ash that no difference could be told from day or night for at least months, possibly years. And so everything that was more than about this big died, including the dinosaurs. That gave us the chance to move up in the world because they were gone. So mammals who were existing at that time then moved into the gap, multiplied and diversified. And so now we live in the age of the mammals instead of the age of the reptiles. But really we just owe that to the asteroid. Here's an old mammal, the ring tailed lemur. And you can see at about 20 million years ago, mammals had gotten this far, where you can see an ape like thing looking here, about 3 million years ago, the common ancestor between human beings and chimpanzees arose. So that if you go back 3 million years, our ancestor and chimp's ancestor look just like this common ancestors. And then the two lines diverged and then we have our own line today and chimps have their line. So that's where we come from. Now the fundamental difference between reptiles and mammals is this for the purpose of the study of empathy. Reptiles lay eggs that are leathery and self sufficient and tough and require no care whatsoever. So here you see an Australian spiny lizard committing its last act of parental devotion, which is to lay the eggs and then leave. So the parental unit is entirely indifferent to the fate of the eggs remaining. They don't require any care or nurturance. Here, sea turtles hatch fully, instinctually knowledgeable, they try to make it to the sea before they get eaten by predators. There's no one around to help them, because the reptilian strategy is to lay tough eggs, hope that the offspring make it, and you take your chances. So 300 million years ago, planet had only fish and some reptiles. Then 200 million years ago, the mammals arose. Mammals have a fundamentally different strategy of reproduction. So that mammals give birth to live, helpless young that require elaborate care or they'll die. So that mammalian young have to be protected from the cold, for instance, they have to be ferried around because they're not fully mobile. They have to be communicated with at regular intervals so that the parental mammal can figure out what it is that the baby mammal needs. They need to be protected from predators. They need to be fed. They need to be bathed, even some alternate methods for bathing. Even when someone else is feeding them. They have to be supervised to make sure that they don't get into trouble. And they have to be taught things. Young mammals learn things from their parents, which is not true of reptiles. And mammal parent and young most often sleep together. Something that we won't touch on so much today. If we look at the brain and we look at the parts from a comparative neuroanatomical standpoint, this part in green is considered the reptilian brain. So if you cut apart reptiles and look at their brains, they have parts that look very similar to this. And in these parts of the brain, we can find ancient hardware for making the body run, regulating the heart and lung function, survival, reflexes, and so forth. Then there it is, the. Then. There we go. Then when mammals arose, we see this part of the brain arising. Because mammals do things. They have qualities and behaviors that reptiles do not like parental bonding to the young, loyalty, affiliation, parental nurturance and protection and care of the young. So they need new brain parts to carry out those new functions. And this part of the brain arises, which in this view is called the cingulate gyrus. The great French neuroanatomist Paul Brokaw was the person who first realized that this part was a mammalian innovation. And he called it the limbic system. And he was using the ancient word lim, l I, m n, which means line. That word actually comes from the medieval times, when monks copied manuscripts and they would draw things in the borders or outline the manuscripts. And the word limb actually comes from lumen, which means light. So Brokaw proposed that this was the line of division in his mind between lower and higher forms of life for our purposes today. It also is the light, say, of empathy emanates from this part and not from this part. So here we are with the reptilian and then the mammalian brain 200 million years ago, Then just a few million years ago, relatively speaking, on the African plain, We got the most recent part in our brain development in which the monkeys became smarter and smarter and smarter. And as they did so, then we got this massive neocortex. And the neocortex here, you see in blue, is a part of the brain that makes us smart. So it enables us to have things like symbolic representation, language, logic, mathematics, physics, technology. The ability to invent things, the ability to imagine things that have not yet happened comes from this part of the brain. And the real difference then, between a monkey and. And a man is this diameter here, which essentially is the diameter of the neocortex. So we're very smart monkeys. So that's the evolutionary part. And now we'll forge ahead into the first mechanism of empathy, which is modeling. And let me tell you a little bit about that. The. The study of empathy really has taken off in neuroscience in the last several years, by which I mean perhaps 10 years. And it begins with this observation that people are contagious, much more contagious than you would suppose. So that, for instance, behavior is contagious. This is a highly contagious behavior. If some people begin to do it, lots of people begin to do it nearby. Someone undoubtedly will begin to do it in the next few seconds because this behavior is so contagious. It's contagious in animals. It's contagious across animals. To us, When you see people or animals doing this, it's hard not to do it yourself. Behavior is contagious. We see one behavior spread to another person. We think, well, why is that? Here's another example of contagious behavior. This is Indiana Jones. Watch the young Alfred Molina behind him after Indy reaches for the. Indy's behavior is contagious. He stands there going like this. The guy behind him starts doing the same thing. Why is that? We'll see in a second. Emotional expressions and emotions are themselves contagious, so that people in the presence of someone showing an emotion begin to show the same emotion themselves, and they begin to feel congruently with that emotion. If you look at this woman, for instance, it's hard to look at her and not become happier than you were before. That's because emotions are contagious. So too tone of voice, surprisingly enough, is contagious. People unconsciously mimic the tones of voice that they listen to so that, say, if we hear a fragment of speech from one of the most famous tones of voice, don't be too proud of this technological terror you've constructed. The ability to destroy a planet is insignificant next to the power of the Force. People who listen to this voice, you can actually measure that their own voice becomes deeper after listening, say, to Darth Vader, than it would if they were listening to a high pitched woman speak. Tone of voice is contagious. Sensations are contagious. So this is actually called the Dr. No effect from the film Dr. No in which a tarantula crawls up Sean Connery's shoulder and then off onto the pillow. A number of people, when they watch this clip, have an irresistible urge to brush their own shoulder, or they get a creepy feeling like something might be touching their own shoulder. Because sensations in among themselves are contagious. Why then are people contagious? Why are behaviors, why are emotions, why is tone of voice? Why are sensations contagious? Why do they leap from one person to another? We can begin to see the answer with this study, which looks at what happens to people when they're stuck in the scanner and then their leg is touched here, one leg, here the other leg, and you see the primary and then the secondary somatosensory cortex lighting up. And then the important part comes when you put people in the scanner and you show them pictures of other people being touched. And what you can see is that the same areas light up in the brain whether you yourself are being touched or whether you are watching someone else being touched. What we understand from this and some other subsequent work that I'll show you is that people understand what they're seeing by modeling it in their own brain. When you see someone being touched, your own brain runs an internal simulation or a model that asks the question, what if that were happening to me? It uses the same neural hardware that you would use if you yourself were being touched. And that's how you understand what it is that happens to other people. Sometimes we see that internal model leak out into actual behaviors on part of the observer. That's why Alfred Molina starts to move his fingers, because he's running a model of Indiana Jones in his head. And it starts to Leak out, we start to see it. Here's an imaging study of people seeing other people having an emotion or having one themselves. We find out that both of those things activate this area here in the premotor cortex, the part part of the brain that readies your face to have an expression. So that this is how you understand other people's expressions. As your brain runs a model that says, well, what if my facial muscles were contracting in that fashion? Then you start to feel what that is, and then you yourself know what it is based on the model in your head. This is a study in which people are subject to pain. A little probe is heated up to an uncomfortable temperature and applied to the calf. Or people watch someone while they're in the scanner having the same thing done to them. What we see is that they both light up. This area in the anterior cingulate cortex that I showed you earlier, this area we know lights up when people are experiencing pain. So that whether you watch someone having pain or whether you yourself are being injured or not injured in this study, but you're being subject to pain, activates the same area. That's how you understand other people's pain, is by modeling it. There's a particularly vivid study from a couple years ago of that entity where one group of people is shown these non harmful events. Opening the door, cutting the cucumber, sticking the foot here, or getting out of the car. Other people are shown the painful versions. Getting the hands stuck in the door, cutting the finger instead of the cucumber, getting your foot stuck under the door, and closing the car door on your foot. Why is it unpleasant even to look on these pictures? It's unpleasant because you're modeling these situations in your own head. And that doesn't feel good. It feels unpleasant to have a model in your own head in which your foot is shut in the car door. That's somewhat unpleasant. It's not as unpleasant as having your foot actually shut in the car door, but it still is somewhat unpleasant. So here we see that people who see these painful events, again, this area in their anterior cingulate cortex that when people are experiencing pain, lights up. So the observers are experiencing pain through the modeling of pain that they're observing. Does that make sense? Now, you remember that former President Clinton used to say that he could feel our pain repetitively. I myself viewed this claim with the greatest skepticism, I must tell you. But if he could have done it, this is how he would have done it. This is the mechanism that he would have modeled it internally in himself. Now I'll show you a clip here. I want you to watch what happens in this clip after the fellow is struck in the groin. I'm okay. I'm okay. Release the meteor. Release the meteor.

Oh.

Oh, no way.

Right in the knee. God damn it. Oh, guys. Way to go. A hole.

All right, hold on.

When I try and find my balls. For God's sakes. One, two and three. Okay. I'm okay. So what do we see here? We see that observers of this event guard their own groins. After the impact to the other fellow, even the woman does it. She makes an uncomfortable motion. Why are they doing this? Because their brains are running a model in their own head that asks the question, well, what if I had been struck in the groin? And it makes them want to guard it as if they had been struck. This is why behavior is contagious. That's why this is unpleasant to look at, is because your brain runs a simulation that says, well, what if a needle were stuck through my forearm? I suspect this is a Photoshop job. Actually, I got this from the Internet, but it looks Photoshopped to me. But that's why it's unpleasant to look on as you're running that simulation in your head. Events like this are what led Mark Twain, long before neuroimaging to remark, by trying, we can easily learn to endure adversity. Another man's. I mean, it's somewhat unpleasant to look at other people's adversity because it's modeled in our own head. Ralph Waldo Emerson, around the same time, also remarked, let us treat men and women well. Treat them as if they were real. Perhaps they are. This is the part right here of your brain that, for the purposes of our talk, and in a mild simplification, generates emotion. So this is the part of your brain that models the emotions that other people feel and exhibit. And this is the part of your brain which is active when you are interpreting and modeling the emotions of other people around you to make sense of them and to find out what it is they're feeling. So that's the modeling function of this portion, which is really the anterior temporal lobe. This thing right here, this kind of thing, thumb, like protrusion is the temporal lobe, and this is the anterior temporal lobe. So these are just some imaging studies in people who are losing empathy because of a degenerative brain disease. And what we see is that their loss of empathy is highly correlated with deterioration in the same region. This anterior temporal lobe that models or that produces emotions in you and models emotions in other people. Similar view here. So this might lead us, say, to the first law of empathy, which is that empathy begins with the COVID modeling of what other people are doing and experiencing. Anton Chekhov, the playwright, once remarked, everything I know about human nature, I learned from me. And that's what he's talking about, that in drawing characters and creating them, he used aspects of himself, as we all do, because in order to understand somebody else, we're using ourselves and as the initial canvas upon which to paint or model somebody else. What happens if this doesn't work so well? What happens if you have some problem in the temporal lobe that prevents you from modeling other people's emotion? What happens is that you become a sociopath. So this is an experimental situation in which people are in an emotion generating paradigm. I think it's the fear of being shocked. Here you see a normal person generating activity in several bayonets. Here's that anterior cingulate cortex, cortex again. Up here in a different view, this part right here is where emotional information is fed into the cortex. This view is the under surface of the brain. Like we took the brain, just flipped it over and looked. Now you can notice the contrast between this and this. In sociopaths. No activation in these emotionally relevant areas. None whatsoever. This next study is even more illuminating in this respect. Similar paradigm, enormous amounts of emotional activation here in the normal person, in the sociopathic or psychopathic person, we see nothing. So that one of the ways to understand sociopathy is an empathic problem that is caused by the inability to model other people's suffering. So the reason that sociopaths are not disturbed by other people's suffering is they cannot model it. There's nothing going on in their brain to make other people's suffering unpleasant to them. And it isn't generally speaking. So let's move on to our next mechanism, which is the projection of the point of view in space, or self projection. So you send out a little imaginary scout and look at what the world looks like from a different point of view. If people are in the scanner and they're asked to imagine that their bodies are in a different position, we find these parts of the brain lighting up. If we ask them to imagine that they themselves, that the self is in a different physical location in space, looking back at their own body, this part of the brain lights up. And you wouldn't necessarily think we would have to have a part of the brain like this, but we do. There's a part of your brain that imaginatively is able to project your point of view in Space. And imagine what other things look like from other parts of space around you, including your own body. So this part is the part that's called upon in understanding an empathy thing. Here's, say, a guy moving behind a bookcase in this imaging study elicits no meaningful activation. But this scenario exhibits activation in this area, which is called the posterior superior temporal sulcus, unfortunately. But that's because it's posterior here in the temporal lobe. And it's superior. It's up a little. And this is the temporal sulcus. What this means is that when the guy pauses behind the bookcase, your brain thinks, I wonder what's going on behind the bookcase. I wonder what it looks like behind there. Why is he pausing? And you send your point of view behind the bookcase to try and figure out what it is that's going on there. This is the projection of your point of view here. If you ask people to imagine a tree falling in a forest, there's no activation over here. But you ask them to imagine. Just imagine an intentional act, like someone coming, sitting in front of you at the theater. And you get activation in this posterior superior temporal focus, because it makes the person wonder, why is that person doing that? What does the screen look like from their point of view? Why do they not realize that my view is now obstructed? Is it that they can't see that my view is obstructed? So you project your point of view in space, and this allows you to understand how other people see the world. When we say other people have a different point of view, we often take this to be a metaphor or a figure of speech. But within the brain, it is a literal truth that we regard other people as existing at other points in space, and they literally have different points of view that we have to collect by sending our own point of view out and imagining what the world looks like from that point of view. This is somewhat effortful, and it's somewhat cognitive, but let's see how you guys do here. So Here's a wall 10ft tall, three balls, A, B, and C, Mr. Red and Mr. Green. Mr. Green says move the large ball. Mr. Red wants to be helpful. Which ball does he move? How many people vote for ball C? How many people vote for ball B? How many people vote for ball A? The correct answer is B, because This is what Mr. Green's point of view is. From his point of view, he can't see that there is a larger ball. So if he says, move the large ball, he can only mean this one. Mr. Red's point of view. He can see all three. In order for him to correctly interpret Mr. Green's request, he has to send his point of view across the room in space and imagine what does it look like to Mr. Green in order to make sense of his statement, in order to interpret it properly. This kind of projection is not automatic. Actually, it's somewhat effortful. And if you don't ask people to try hard, they often get this wrong. This particular question, the existence of the faux pas is an instance in social life in which one person fails to send his point of view across the room and imagine what he says. Imagine how that is going to be perceived by each of the people in the room. So I'll show you just a brief faux pas and you can tell that one of the people will say something. That had they projected their point of view out in space, they would have known that they should not say, Jinx is strictly a house cat. You can't let him outside because he also lacks outdoor survival skills. That's just one of those things, isn't it, sweetheart? I don't think Greg will be playing.

With Jinxy too much.

He hates cats, Pam. I don't hate cats. I don't. I don't hate cats. I just happen to be more of a dog lover, that's all. Yeah.

Yeah.

Well, it's okay if you hate cats, Greg. No, I don't. I don't hate cats at all. That's okay. Just be honest about it. There's some things I hate. I. I'm being honest. Really? Like what? So had his fiance effortfully used her ability to apprehend other people's point of view, she would have known that she should not say this. There are people who have great difficulty detecting faux pas, and we'll talk about that in just a second. Here is another failure to model other people's minds. Here you see Dilbert and the pointy haired boss. Dilbert says, I didn't think it was possible, but for the past month I've done my own job plus Ted's, and done them well. I know you're marveling at my accomplishment and you're wondering how you can reward me. And the pointy haired boss says, maybe I can fire Carl and make this idiot do his job too. Dilbert is failing to project his point of view in space and to imagine what the situation looks like from the point of view of the boss. So the second law of empathy that we might postulate is that empathy proceeds through the imaginative projection of the mind's. Eye through space, time and identity. And so what if this doesn't work so well? What if people have trouble activating this posterior superior temporal sulcus and telling point of view from other people? We wind up then probably in the autistic spectrum. So at its mildest. Autistic. Mild autistic spectrum can be a kind of social dyslexia. That people are socially clumsy. They emit many faux pas. They fail to accurately send their point of view and imagine what other people will think about what they're saying and doing. And at the severe end, it can be quite serious. The trio of deficits. Impaired communication, impaired reciprocity, and restricted interest. This is a functional imaging study. Here's our posterior. They don't put in here, but that's what it is. Superior temporal sulcus. In normal people, when you show them a face, they immediately light up this area because a normal person thinks, oh, there's another person. I wonder what the world looks like from that point of view. And they send their projection, their mind's eye out in space. If we look at people in the autistic spectrum do not do this. So there's no activation here in superior temporal sulcus. Now, we don't know what the primary deficit is in the autistic spectrum. So I'm not saying this is the primary deficit. It is a notable deficit, though. And people on the autistic spectrum have a hard time doing this. This is another thing they have a hard time doing. These are normal people listening to the human voice. And you see activation here in the temporal lobe language centers. And maybe it's leaking up in here into the posterior superior temporal sulcus, telling them someone's speaking. That person is another person and has a point of view in the autistic spectrum, we don't see that activation at all. And one of the interesting things about people in the autistic spectrum is they do not necessarily understand that spoken speech has a communicative intent. It is not obvious to them that that's the case, because if they hear spoken speech, there's nothing in their brain that says there's another person speaking with a point of view. They may want to communicate with you. In fact, as Simon Baron Cohen, who's one of the leading researchers in this area, notes that a number of autistic adults have told him that it was surprising to them to learn that when someone looked at them and said their name, that meant that they wanted to communicate or wanted to initiate a conversation. They did not know that off the bat. So what causes autism. This is actually the leading theory of autism. Not this. I just got this off the web. But the idea behind these two sets of cartoons is fundamentally correct. There really is a male brain and there really is a female brain. And the difference between them is perhaps not this, but more this. Say that there's a male version or model of the brain and there's a female version, and the male version is specialized for certain things, including being interested in technology, machines, numbers and systems, and that the female brain is specialized for other things, being interested in relationships, communication, empathy, and perhaps language. And the maleness theory of autism postulates, or the autistic spectrum postulates, that people in the autistic spectrum have a hyper male brain. They have a brain that is excellent at things involving numbers, systems, machines, but a brain that has a lot of trouble handling things like language sometimes, or relationships or empathy. So was Einstein in the autistic spectrum, do you think? Could be. Einstein didn't speak until he was 4, which is a significant language delay. His first words were cold soup, which is unusual because kids first words are usually mama or dada. And he drove everybody crazy when he was a little kid because he repeated back things that people said word for word, which is called echolalia, that your mother says, would you go pick up the newspaper? And the kid says, would you go pick up the newspaper? This drove people crazy. This is sometimes seen in kids in the autistic spectrum. Einstein himself had this observation to make about himself. My passionate sense of social justice and social responsibility has always contrasted oddly with my pronounced lack of need for direct contact with other human beings and human communities. I am truly a lone traveler, and I have never belonged to my country, my home, my friends, or even my immediate family, or with my whole heart. In the face of all these ties, I've never lost a sense of distance and a need for solitude. So the autistic spectrum is not all bad because Einstein did a lot of great stuff. It's just a different way of perceiving the world. Now let's turn to the last of our three empathic mechanisms, adjusting the balance between self and other. So if you're in your brain, you're going to have your own emotions and your own concerns, and then you're also going to be modeling other people's emotions and their concerns. And then the question arises, well, how are we going to balance these two things? Most people balance it this way, that their own self counts for a lot more than the things that they are balancing. Some people do it this way, that the other counts for way too much. So the question arises, how are you going to balance self and other? We all understand what the curse of ignorance is. Say that people who don't know things don't know them. But in the area of empathy, one of the things that's a surprising pitfall is the curse of knowledge that in your own mind you know things already, maybe a lot of things. And it's hard to imagine what it's like not to know those things. It's hard to imagine what it's like not to be you, because in order to imagine that, you would have to suppress all the stuff that you know. In order to imagine what other people's minds are like, you would have to erase your own blackboard, which is hard and time consuming. So in studies, for instance, if you take hungry people and you offer them food, and before they eat it, you say, how hungry will you be after you have eaten this? They consistently overrate how hungry they will be. They say they will be much hungrier than they actually are. And the reason is because they have trouble imagining their future self. Their current self is hungry now, and that dominates their view of the world. Similarly, let me try this experiment. I'll show you something. And the minute that you know what it is, say now, each one of you individually, something will emerge. So just as a practice, everybody say now. Now. Now. Okay, as soon as you know what this is, say now. Ready? All right. Now we'll run the experiment again. But this time imagine that you're someone who has never seen this before, and say now, when you think that person would know what this is. Ready? Go. As soon as that person would know what this is, they say no. So your first answer had a peak at nine seconds, your second answer, a peak at six seconds. So it's hard to imagine what it's like not to know this. In order to do that, you would have to actively suppress your own knowledge, which is hard to do. And so here you are. Now, who you are going to be in the future is a different person that is hard to empathize with. Who you were in the past is a different person that's hard to empathize with. So you can imagine how hard it is to identify or empathize with other people, since it's hard even to identify with your future or past self. This is the part of the brain that carries out this activity of inhibiting your own stuff so that you can model somebody else's stuff. This is a neocortical innovation. Here we see this is squarely in the neocortex. And it's inhibitory in nature, so it inhibits what's called sometimes the pre potent self perspective. Why don't doctors have any empathy? This points to another reason why empathy needs to be limited is that in this imaging study, people are shown these innocuous pictures of the Q tip touching the lips, hand or foot, and these images in which a needle is being stuck in into the lips, hands and foot. And if we look at how the average person reacts, and in this case doctors who are used to sticking needles into people, what we see here is that the average people activate the part of their brain that would model pain. Here's the insula, the part of their brain that models bodily sensations. Here's that painful area of the anterior cingulate cortex. Again, the control people say that's painful. These are the doctors, and they have activated their. Sometimes this is called the anterior parasingulate gyrus or part of the medial frontal cortex. But this is the inhibitory part of emotion. So the doctors have managed to inhibit their own painful modeling of somebody else's pain, so much so that they don't really think it's all that painful. So that if you ask them, well, how intense is the pain from sticking a needle into this part of your body? The novice says this, the expert says this, so it's not really painful. How unpleasant is it? Here's the novice, here's the expert. So when you go to the doctor and they say this won't hurt very much, they're telling the truth as they know it, which is that they have so suppressed their experience of your pain that it doesn't hurt very much. If you've ever been to the orthopedic surgeon, as I have, for instance, and there's all kinds of grisly things that happen to you, and they say, oh, this will cause a little discomfort. This is why they're able to do this. So is empathy an unmitigated social good? It isn't in the sense that if everybody were very empathic, we wouldn't have any orthopedic surgeons because somebody has to be in the room with the person screaming and then say, well, let me move your arm in this horrible way that will make you scream more. So there is a useful social position for people who do not have much empathy or they can manage to suppress it. And we need those people. A lot of people assume naively that empathy is just an unmitigated social good. The more of it we have, the better off we all are. Not necessarily true. Someone who's your surgeon, you probably don't want them fainting at the sight of blood or throwing up if you have a needle stuck through your arm. So this we might call the third law of empathy. That empathy finishes with fine tuning the balance between self and other, which is necessary in order to understand what other people are doing. And it's also necessary in a social sense that people can't simply be swamped by the empathic stuff that comes from other people. So again, this part of the brain in the medial prefrontal cortex carries us out. Well, what if this doesn't work so well? What if people don't inhibit their own stuff very well? Well, there's a word for these people, and we call them selfish, literally, which is that their self counts too much in their mind because they are selfish. Or we call them, sometimes we call them narcissistic. There are a couple of useful typologies of narcissism that I'll just describe briefly here. You can imagine that one way to have insufficient inhibition of your own self is to have too much self. Like, say you have tremendously strong emotions that are too much for this breaking mechanism to inhibit. It's just too much stuff. Then you would have a hot narcissism. So people like this tend to be, say, characterologically artistic. People often have a hot narcissism. They're so emotional that they can't reign it in. People who are experiencing intense emotion of any sort tend to be not very empathic, partly because of this mechanism. So someone having a panic attack or someone having a terrible depression, the people are usually not very empathic because their emotions have run away with them. There are people whose emotions run away with them all the time, say, in a narcissism sense. And we might call that a hot narcissism typology. There's also, you can imagine another scenario in which your emotions aren't that strong, but your inhibitory control mechanism is weak. And so it's just not up to the task of inhibiting your own stuff. And we might call this a cold kind of narcissism in adults. When adults have insufficient inhibitory mechanisms, the things they tend to seek out are money, drugs, power and sex. So that these people aren't inspired, but they are motivated by these other things that they want to acquire. Children are in this category because their inhibitory mechanisms are often not very good. So if you've ever tried to play a board game with a child, say the kid keeps Insisting that it's his turn every time, because it's hard to inhibit long enough to let somebody else take their turn. There are also, I think this is not well known enough, so I'll just include this. Everybody knows mostly that when someone says unabashedly, well, it's all about me, and they act selfishly, that they may have some narcissistic traits. What is less familiar to people is that there's also a person who says, well, it's all about you. I'm really doing this for other people. But they still act selfishly. This also is a kind of narcissism that is probably more insidious and difficult for people to recognize. Nevertheless, it is in the world all over. So when somebody says, oh, I'm just doing this for you, or it's all about other people, or really I'm just helping other people, then you have to look at what it is they're actually doing and whether it benefits the other people or whether it seems to benefit themselves more. So this is where we've been talking about empathy, which arose as a mammalian innovation, as part of the survival imperative of mammals, that they must know what is going on inside other mammals if they're to become successful mammalian parents or the young are going to survive into the next generation. And partly because of that, we have this modeling mechanism which enables us to feel into other people. We can internally understand or feel what is their sensation, what is their emotion, what does their action feel like to them? And then we have a couple of later, more cognitive, more thinky kind of empathic mechanisms. One, the effortful cognitive projection of the self perspective in space. And then the ability to adjust the balance between self and other so that a person can inhibit their own pre potent self perspective. I'll leave you with one final thought and then we'll go to questions in terms of this modeling thing. When people, for instance, move rhythmically to music, say when they tap their foot to a musical beat, they are exhibiting the modeling function of empathy. That when you hear a regular sound like this, your brain interprets it in terms of the motor action it would take to produce that sound. And that is why you see the behavior leaking out into people's actual motor movements that they're modeling. Well, what if my foot was hitting the ground at this tempo? That would make this sound. And that model leaks out into their actual behavior. So that when you notice yourself tapping or snapping your fingers or clapping to the beat? This is what it's from. It's from this ancient modeling empathy Mechanism that allows you to model and feel into communicative signals coming from other people. There's that. All right, so let's stop now and then and do some questions. Question there.

In the male model and female model brains, how does that play out for homosexuals? Like, is that in the brain at.

All or it is in the brain. Does anybody hear that question? How does maleness and femaleness play out in the brains of, say, male homosexual men? Without getting into too much technical detail, it's fairly clear now that most gay men have a partially feminized male brain in a different part of the brain than we were looking at. But that is why, for instance, gay men often have female identified interests like relationships or empathy or communication or language. That gay men are much more interested in those things than the average straight man is. It's also, it's true of functions that have nothing to do with empathy. For instance, men throw objects more accurately than women. They hit the target more accurately. Gay men throw with an accuracy that is intermediate between men and women. So it's relatively clear that gay men have a partially feminized male brain and they do tend to be more empathic than the average man. In general, women are more empathically skilled than men. That's not true of every man and every woman. You can find men who are very empathic, you can find women who aren't. But as a group, women are more empathically skilled. Questioner can we say that the depictions of pain and destruction and disasters in literature and art are designed to blunt our sense of empathy? Our depictions of destruction and pain in art designed to blunt our sense of empathy, I would guess, are designed to heighten it or evoke our sense of empathy. That say, if art work works, it makes you feel something and often, say in a novel in which you identify with the characters, if something bad happens to them, it's somewhat painful for you. So I think good art evokes that. I think entertainment blunts it. So say if you see a mass market entertainment film in which I just saw the Bruce Willis film, not to say it's bad, which it's not, but Bruce Willis is tossed about like a rag doll throughout the course of the film. Nothing bad happens to him. He doesn't break any bones, he doesn't suffer visibly at any point. That I think does blunt our empathy. Entertainment. But art shouldn't do that. And actually that's one of the fundamental distinctions between art and entertainment that's worth describing.

I have a two part question about the male female Brighton Theory of autism. The first is that it's my understanding that women report feeling more empathy, and they recall feeling more empathy, but if you test them online as an event is happening, they actually report the same amount of empathy as men. So I'm curious, how strong is the neuroscientific evidence for showing that women actually experience more empathy and more relational concerns than men on average? Because, of course, these are overlapping distributions. And then the second question is, what does it actually mean for autism to be an extreme form of the male brain? Does that mean something beyond just an analogy to a cultural stereotype? Or does that actually tell us something about the causal roots of autism? And is there any evidence for that?

Sure. In terms of the first question, there's quite a bit of evidence, actually. And the best evidence comes from studies in which, say, people witness an event, say they watch a film, and someone stops them at periodic times and asks them, what is that person's feeling? That it's clear that men are less empathically accurate than women as a group. But as a group, they are less empathically accurate. One of the things that we know, for instance, from primate research, getting to your second part of the question is that you might think, well, boy babies play with balls and trucks because we tell them to, and girl babies play with dolls because we tell them to. But actually, primate rhesus monkeys, the male infants, male rhesus monkeys prefer to play with balls and trucks spontaneously, and the female infants prefer to play with dolls spontaneously. And no one has told them or modeled the behavior. So it's clear that there is a spontaneous affinity in maleness for machines and technology and artificial gadgets, for lack of a better word. And that there's a spontaneous preference in women for relationship empathy. And that probably includes language, because, of course, one of the ways in which men, male, and female schoolchildren differ is that female schoolchildren are a little better at language activities than male schoolchildren. In the autistic spectrum, the hyper male brain, we see frank language impairment a fair amount of the time, which may represent, say, the extreme end of that maleness. So it's likely that is more than a metaphor, that it's a fundamental biological distinction that has utility in evolution. Say, the fact that women have an interest in empathy is not an accident. It's a biological necessity in an evolutionary sense, if they are to rear and protect and nurture children or offspring. So men and women are bred by evolution for different tasks. Men are bred for combat and hunting and fighting. And it appears in some Sense that men are bred for making gadgets. One of the ways we can tell that men are bred for combat is that men are larger and more muscular than women. Not every man is not larger than every woman. But as a group, men are larger and more muscular. They are bred for physical combat in some sense. So it probably is more than just a metaphor.

Thank you, sir.

I guess to stay with this theme, and this is probably the popular topic. Excuse me for my voice, I just lost it yesterday. But just going back to this issue of male, female brain, sort of the major lesson from the emerging literature on developmental neuroscience is that the brain is incredibly plastic. You could have lesions to the hippocampus, and still children will recover language by the time they get to fourth or fifth grade. So we see this amazing plasticity and also sort of the sex differences. We classically see sort of David Buss work across cultures where he shows women really focus on status, men really focus on parents. All of that is sort of really tempered. When Alice Eagley and Wendy would look at it and they say, look, it's a social effect. If you look at really egalitarian societies, all these effects go away. So, oh, you just lost your light. But ultimately my question becomes, well, even if we see these differences in adults, how much can we really say that it's really biological versus just socialization? Because it seems really hard to divorce those two patterns, especially in current societies where men and women are really very differently socialized from a very early age.

Well, one of the data sets in which you see that is in the primates, say, who are not socialized in any particular way. You know what's a great book on the subject is the Essential Difference by Simon Baron Cohen, which is a terrific book. I think it's likelier, actually that the evidence falls on the side of the neural hard wiring than it does on the side of socialization. I think that's likely. That's. That's my reading of the evidence. I'm sure people could have an interesting debate or argue those points. The brain has plasticity, but not infinite plasticity, particularly around things that are fundamental to it. So, as you might know, say, in the 60s and 70s, when kids, say, had inadvertent genitalia destruction at birth, which happens sometimes during circumcision because they use an electrical cautery iron, and every so often there's a short out, and there you go. The prevailing theory was, well, we can raise these kids as girls. It happens within a few weeks of birth. We can socialize them as girls. And they won't know the difference. And that was tried and it was a disastrous failure, actually. Those kids grown to adulthood despite the fact that they'd been socialized as girls, felt like guys. So I don't think the brain is not infinitely plastic. It has limitations, particularly among its more fundamental units. And gender and sex are profoundly fundamental because they have a huge impact on reproductive fitness. And so among the parts of the brain that it's hard to tinker with and get away with, those are some of those parts. So I'm less friendly to the socialization hypothesis, although I know some people are.

Yeah. Just one interesting piece of research to follow up on that. They did some really amazing work recently at mit where I believe they took rats. And they disconnected the orbital lobes from the eyes, the pathway to the orbital lobes, and connected it to sort of the temporal lobes, the parts that really sort of monitor auditory impulses. And also they looked at them later on in life, and the temporal lobes morphed to mirror, sort of the occipital lobes, and they started to take on the function of sight. And like, that was sort of an amazing work to me to illustrate sort of the plasticity on, you know, vision and hearing, you would think, very defined regions, very defined systems. And here we see plasticity even at that level. So that's where.

Yeah, that I think is much less surprising innately than say, a gender based plasticity. I think just as someone who works in the field, it's interesting and it's not devoid of interest, but it doesn't strike me as so surprising. I fall off my seat.

Thank you very much.

Thank you. That's all the time we have for questions right now. Thanks very much.