Lisa Feldman Barrett: Counterintuitive Ideas About How the Brain Works | Lex Fridman Podcast #129
the following is a conversation with lisa feldman barrett a professor of psychology at northeastern university and one of the most brilliant and bold thinkers and scientists i've ever had the pleasure of speaking with she is the author of a book that revolutionized our understanding of emotion in the brain called how emotions are made and she's coming out with a new book called seven and a half lessons about the brain that you can and should pre-order now i got a chance to read it already and it's one of the best short whirlwind introductions to the human brain i've ever read it comes out on november 17th but again if there's anybody worth supporting it's lisa so please do pre-order the book now lisa and i agreed to speak once again around the time of the book release especially because we felt that this first conversation is good to release now since we talk about the divisive time we're living through in the united states leading up to the election and she gives me a whole new way to think about it from a neuroscience perspective that is ultimately inspiring of empathy compassion and love quick mention of each sponsor followed by some thoughts related to this episode first sponsor is athletic greens the all-in-one drink that i start every day with to cover all my nutritional bases that i don't otherwise get through my diet naturally second is magic spoon low carb keto friendly delicious cereal that i reward myself with after a productive day the cocoa flavor is my favorite third sponsor is cash app the app i use to send money to friends for food drinks and unfortunately for the many bets i have lost to them please check out these sponsors in the description to get a discount and to support this podcast as a side note let me say that the bold first principles way that lisa approaches her study of the brain is something that has inspired me ever since i learned about her work and in fact i invited her to speak at the agi series i organized at mit several years ago but as a little twist instead of a lecture we did a conversation in front of the class i think that was one of the early moments that led me to start this very podcast it was scary and gratifying which is exactly what life is all about and it's kind of funny how life turns a little moments like these that at the time don't seem to be anything out of the ordinary if you enjoy this thing subscribe on youtube review it with five stars and apple podcast follow on spotify support on patreon or connect with me on twitter at lex friedman and now here's my conversation with lisa feldman barrett since we'll talk a lot about the brain today do you think let's ask the craziest question do you think there is other intelligent life out there in the universe honestly i've been asking myself lately if there's intelligent life on this planet uh you know i ha i i have to think probabilities suggest yes and also secretly i think i just hope that's true it would be really um i know scientists aren't supposed to have hopes and dreams but uh i i think it would be really cool and i also think it would be really sad if it if it wasn't the case if we really were alone that would be that that would seem profoundly sad i think so it's exciting to you not scary yeah no you know i take a lot of comfort and curiosity it's a great it's a great um resource for dealing with uh stress so um i'm learning all about mushrooms and uh octopuses and you know all kinds of stuff um and so for me this counts i think in the realm of awe but also i think i'm somebody who cultivates awe deliberately on purpose to feel like a speck you know i i find it a relief occasionally it feels small to feel small in a profoundly large and interesting universe so maybe to dig more technically on the question of intelligence do you think it's difficult for intelligent life to arise like it did on earth from everything you've written and studied about the brain how magical of a thing is it in terms of the odds it takes to arise yeah so you know magic is just don't get me wrong i mean i like i like a magic shirt as much as the next person my husband was a magician at one time but you know magic is just a bunch of stuff that we don't really understand how it works yet so i would say from what i understand there are some major steps in the course of evolution that at the beginning of life the step from single cell to multicellular organisms things like that which are really not known i think for me the question is not so much um could it you know what's the likelihood that it would happen again as much as um what are the steps and how long would it take and if it were to happen again on earth would would we end up with the same you know menu of life forms that we currently have now and i think the answer is probably no right there's just so much about evolution that is stochastic and driven by chance but the question is whether that menu would be equally delicious meaning like there'd be rich complexity of the kind of like would we get dolphins and humans or whoever else falls in that category of weirdly intelligent seemingly intelligent however we define that well i think that has to be true if you just look at the range of creatures who've gone extinct i mean but if you look at the range of creatures that are on the earth now it's incredible and you know it's sort of tried to say that but it actually is really incredible um particularly i don't know i mean animals there are animals that seem really ordinary until you watch them closely and then they become miraculous you know like certain types of birds which do very miraculous things uh um build you know bowers and do dances and all these really funky things that are hard to explain uh with a standard evolutionary story although you know um people have them birds are weird they do a lot of for mating purposes they they have a concept of beauty i haven't quite maybe you know much better but it doesn't seem to fit evolutionary arguments well it does fit well it depends right so i think you're talking about the evolution of beauty the um book that was written recently by was it from um without his name richard from i think no i didn't oh it's a great book it's very controversial though because he is argues make an argument that the the question about birds and some other animals is why would they engage in such metabolically costly um displays when it doesn't improve their fitness at all and the answer that he gives is the answer that darwin gave which is sexual selection um not natural selection but you know selection can occur for all kinds of reasons there could be artificial selection which is when we breed animals right which is actually how darwin that that observation helped darwin come to the idea of natural selection oh interesting um and then there's sexual selection um meaning and the argument that that um i think his name is from uh makes is that um that it's the pleasure the selection pressure is the pleasure of female birds which as a woman and um as someone who studies affect that's a great answer i actually think there probably is natural i think there is an aspect of natural selection to it which he maybe hasn't considered but you were saying the reason we brought up birds is the the life we got now seems to be quite yeah so you peek into the ocean peek into the sky there are miraculous creatures look at creatures who've gone extinct and you know in science fiction uh stories you couldn't dream up something as interesting so my guess is that you know intelligent life evolves in in many different ways even on this planet uh there isn't one form of intelligence there's not one brain that gives you intelligence there are lots of different brain structures that can give you intelligence so my guess is that the menagerie might not look exactly the way that it looks now but it would certainly be as as interesting but if we look at the human brain versus the brains or whatever you call them the mechanisms of intelligence in our ancestors even early ancestors that you write about for example in your new book what what's the difference between the the fanciest brain we got which is the human brain and uh the ancestor brains that it came from yeah i think it depends on how far back you want to go you go all the way back right in your book so what's the interesting comparison would you say well first of all i wouldn't say that the human brain is the fanciest brain we've got i mean an octopus brain is pretty different and pretty fancy and they can do some pretty amazing things that we cannot do you know we can't grow back limbs we can't change color and texture we can't comport ourselves and squeeze ourselves into a little crevice i mean these are things that we invent these are like superhero abilities that we invent in stories right we can't do any of those things and so the human brain is certainly um we can certainly do some things that other animals can't do that seem pretty impressive to us but but i would say that there there are a number of animal brains which seem pretty impressive to me that can do interesting things and really impressive things that we can't do i mean with your work on how emotions are made and so on you you kind of repaint the the view of the brain as um as less glamorous i suppose than you would otherwise think or like i guess you draw a thread that connects all brains uh together in terms of homeostasis and all that kind of stuff i yeah i wouldn't say that the that the human brain is any less miraculous than anybody else would say i just think that there are other brain structures which are also miraculous and i also think that there are a number of things about the human brain which we share with other other vertebrates other animals with backbones but um that are that we share these miraculous things but we can do some things in abundance and we can also do some things with our brains together working together that other animals can't do or at least we haven't discovered their ability to do it yeah this social thing how i mean that's one of the things you write about uh what's uh how do you make sense of the fact uh like the book sapiens and the fact that we're able to kind of connect like network our brains together like you write about i'll try i'll try to stop saying that uh is that is that like some kind of feature that's built into there is that unique to our human brains like how do you make sense of that what i would say is that our ability to coordinate with each other is not unique um to humans there are lots of animals who can do that and we um but what we do with that coordination is unique because of some of the structural features in our brains and it's not that other animals don't have those structural features it's we have them in abundance so you know the human brain is not larger than you would expect it to be for a primate of our size if you took a chimpanzee and you ex grew it to the size of a human that chimpanzee would have a brain that was the size of a human brain so there's nothing special about our brain in terms of its size there's nothing special about our brain in terms of the um the basic blueprint that builds our brain from an embryo is the basic blueprint that builds all mammalian brains and maybe even all vertebrate brains um it's just that because of its size and particularly because of the size of the cerebral cortex which is the um a part um that people mistakenly attribute to rationality yeah mistakenly is that where all the clever stuff happens well no it really isn't and i will also say that lots of clever stuff happens in animals who don't have a cerebral cortex but right um but uh but because of the size of the cerebral cortex and because of some of the features that are enhanced by that size that gives us the capacity to do things like build civilizations um and coordinate with each other not just to manipulate the physical world but to add to it in very profound ways like you know other animals can cooperate with each other and use tools um we draw a line in the sand and we make countries and we even then we create you know uh we create citizens and immigrants but also ideas i mean the countries are centered around the concept of like ideas well my well what do you think a citizen is and and an immigrant those are ideas those are ideas that we um impose on reality and make them real and then they have very very serious and real effects physical effects on people what do you think about the idea that a bunch of people have written about dawkins with memes which is like ideas are breeding like we're just like the canvas for ideas to breed in our brains so this kind of network that you talk about of brains it's just a little canvas for ideas to then yeah eat against each other and so on i i think it's a rhetorical tool it's cool to uh think you know think that way so um i think it was michael pollan i don't remember if it was in the botany of desire but it was in one of his early books on um on botany and gardening where he wrote about um and he wrote about uh you know plants sort of utilizing humans for their own you know evolutionary purposes which is kind of interesting you can think about a human gut in a sense as a propagation device for the seeds of you know tomatoes and what what have you so it's kind of cool um so i think i think rhetorically it's an interesting device but you know ideas are as far as i know invented by humans propagated by humans um so you know i i don't think they're separate from human brains in in any way although it would it is interesting to to think about it that way well of course the ideas that are using your brain to communicate and write excellent books uh and they basically picked you uh lisa as an effective communicator and and thereby are winning so that's an interesting world view to think that there's particular aspects of your brain that are conducive to certain sets of ideas and maybe those ideas will win out yeah i think the way that i would say it really though is that there are many species of animals that influence each other's nervous systems that regulate each other's nervous systems and they mainly do it by physical means they do it by chemicals scent they do it by you know so so termites and ants and bees for example use chemical scents mammals like um like rodents use scent and they also use uh hearing audition and that little bit of vision um primates you know non-human primates add vision right and i think everybody uses touch humans as far as i know are the only species that use ideas and words to regulate each other right i can text something to someone halfway around the world they don't have to hear my voice they don't have to see my face and i can have an effect on their nervous system and ideas the ideas that we communicate with words i mean words are in a sense a way for us to do mental telepathy with each other right i mean i'm not the first person to say that obviously but how do i control your heart rate how do i control your breathing how do i control your actions with words it's because those words are communicating ideas so you also write i think let's go back to the brain you write that plato gave us the idea that the human brain has three brains in it three forces which is kind of a compelling notion uh you disagree first of all what are the three parts of the brain and uh why do you disagree so plato's description of the psyche which for the moment we'll just assume is the same as a mind there are some scholars who would say you know a soul a psyche a mind those aren't actually all the same thing in ancient greece but we'll just for now gloss over that so plato's idea was that and it was a it was a description of really about moral behavior and moral responsibility in humans so the idea was that you know the human psyche can be described with an um a metaphor of two horses and a charioteer so one horse for instincts like feeding and fighting and fleeing and reproduction i'm trying to control my salty language which apparently they print in england like i actually tossed off of f s yeah f f okay yeah yeah i was like you printed that i couldn't believe you printed that without like the stars or whatever no no no there was full print yeah they also printed the a b word and it was really quite yeah anyways we should we should uh learn something from england indeed anyways but instincts and then the other horse represents emotions and then the cherry tier represents rationality which controls you know the two beasts right and um fast forward you know couple of centuries and uh in the middle of the 20th century there was a very popular view of brain evolution which suggested that you have this uh reptilian core like a lizard bra an inner lizard brain for instincts and then wrapped around that evolved on layer on top of that evolved a limbic system for uh in mammals so the novelty was in a mammalian brain which uh bestowed mammals with uh gave them emotions the capacitive emotions and then um on top of that uh evolved uh a cerebral cortex um which in in largely in primates but but very large in in humans um and it's not that i personally disagree it's that as far back as the 1960s but really by the 1970s it was shown pretty clearly with evidence from molecular genetics so peering into cells in the brain to look at the molecular makeup of genes that the brain did not evolve that way and the irony is that um you know the the idea of the the three-layered brain with an inner lizard you know that hijacks your uh hijacks your behavior and causes you to do and say things that uh you would otherwise not or maybe that you will regret later that idea um became very popular was popularized by uh carl sagan in the dragons of eden which won a pulitzer prize in 1977 when it was already known pretty much in evolutionary neuroscience that the whole uh narrative was a myth so well the narrative is on the the way it evolved but do you i mean again it's that problem of it being a useful tool of conversation to say like there's a lizard brain and there's a like if i get overly emotional on twitter that was the lizard brain and so on uh but do you no i don't think it's useful i think it's a i think that is it is is it uh is it useful is it accurate i don't think it's accurate and therefore i don't think it's useful so i here's what i would say you know i think that um the way i think about philosophy and science is that they are useful tools for living and in order to be useful tools for living they have to help you make good decisions the try and brain as it's called this this three-layer brain the idea that your brain is like an already baked cake in and you know the cortex cerebral cortex is just layered on top like icing the idea that idea is the foundation of the law in most western countries it's the foundation of uh economic theory and it largely and it's a great narrative it sort of fits our intuitions about how we work but it also um it's in addition to being wrong it lets people off the hook for uh for nasty behavior you know um and it also suggests that emotions can't be a source of wisdom which they often are in fact you you would not want to be around someone who didn't have emotions that would be that's a psychopath right i mean that's not someone you you know want to want to really uh have have that person deciding your outcome so i guess my and i could sort of go on and on and on but my point is that um i don't think i don't think it's a useful narrative in the end what's the more accurate view of the brain that we should use when we're thinking about it i'll answer that in a second but i'll say that even our notion of what an instinct is or what a reflex is is not quite right right so if you look at evidence from um ecology for example and you look at animals in their ecological context what you can see is that even things which are reflexes are very context-sensitive um the the brains of those animals are executing so-called instinctual actions in a very very context-sensitive way and so you know even when a physician you know takes the you know it's like the idea of your patellar uh reflex where they hit you know your patellar tendon on your knee and you you kick the the force with which you kick and so on in is influenced by all kinds of things it's it's a reflex isn't like a robotic uh response and um so i think a better way is a way that to think about how brains work is the way that um matches our best understanding our best scientific understanding which i think is really cool uh because it's really counterintuitive so how i came to this view and i'm certainly not the only one who holds this view i was reading work in on neuroanatomy and the the view that i'm about to tell you was sugges strongly suggested by that and then i was reading work and signal processing like by engineer electrical engineering and similarly it the work suggested that that the research suggested that the brain worked this way and i'll just say that i was reading across multiple literatures and they were who don't speak to each other and they were all pointing in this direction and so far although some of the details are still up for grabs the general gist i think is i've not come across anything yet which really violates and i'm looking um and so the idea is something like this it's very counterintuitive um so the way to describe it is to say that your brain doesn't react to things in the world it's not it to us it feels like our eyes and our um our windows on the world we see things we hear things we we react to them um in psychology we call this stimulus response so your face is your voice is a stimulus to me i receive input and then i react to it uh and i might react very automatically you know system one uh and uh oh but i also might execute some control where i maybe stop myself from saying something or doing something and um more in a more reflective way execute a different action right that's system two the way the brain works though is it's predicting all the time it's constantly talking to itself constantly uh talking to your body uh and it's constantly um predicting what's going on in the body and what's going on in the world and making predictions and the information from your body and from the world really confirm or correct those predictions so fundamentally the thing that the brain does most of the time is just predict like talking to yourself and predicting stuff about the world not like this dumb thing that just senses in response senses yeah so the way the way to think about it is like this you know your brain is uh trapped in a dark silent box yeah that's very romantic of you um which is your skull and the only information that it receives from your body and from the world right is through the senses through the sense organs your eyes your ears and you have a sense sensory data that comes from your body that you're largely unaware of uh to your brain which we call interroceptive as opposed to exteroceptive which is the world around you and but your brain is receiving sense data continuously which are the effect of some set of causes your brain doesn't know the cause of these sense data it's only receiving the effects of those causes which are the data themselves and so your brain has to solve what philosophers call an inverse inference problem how do you know when you only receive the effects of something how do you know what caused those effects so when there's a flash of light or a change in air pressure or a tug somewhere in your body how does your brain know what caused those events so that it knows what to do next to keep you alive and well and the answer is that your brain has one other source of information available to it which is your past experience it can reconstitute in its wiring past experiences and it can combine those past experiences in novel ways and so we have lots of names for this in psychology we call it memory we call it perceptual inference we call it simulation it's also we call it concepts or conceptual knowledge we call it prediction basically if we were to stop the world right now stop time your brain is in a state and it's representing what it believes is going on in your body and in the world and it's predicting what will happen next based on past experience right probabilistically what's most likely to happen and it begins to um prepare your action and it begins to prepare your the prepare your experience based so it's anticipating the sense data it's going to receive and then when that those data come in they either confirm that prediction and your action executes because the plan has already been made or um it where there's some uh sense data that your brain didn't predict that's unexpected and your brain takes it in we say encodes it we have a fancy name for that we call it learning your brain learns and it updates its storehouse of knowledge which we call an internal model and uh that you so that you can predict better next time and it turns out that predicting and correcting predicting and correcting is a much more metabolically efficient way to run a system than constantly reacting all the time because if you're constantly reacting it means you have no you can't anticipate in any way what's going to happen and so the the amount of uncertainty that you have to deal with is uh overwhelming to a nervous system metabolically costly i like it and so what is a reflex a reflex is when your brain doesn't check against the sense data that the potential cost to you is so great maybe because you know your life is threatened that your brain makes the prediction and executes the action without checking yeah so but prediction is still at the core that's a beautiful vision of the brain i wonder from almost an ai perspective but just computationally is the brain just mostly a prediction machine then like is the perception just the nice little feature added on top like the both the the integration of new perceptual information i wonder how big of an impressive system is that relative to just the big predictor model construction well i think that we can we can look to evolution for that for one answer which is that when you go back you know 550 million years give or take we you know the world was populated by creatures really ruled by creatures without brains um and um you know that's a biological statement not a political statement really world war ii dinosaurs dumb you're talking about like oh no i'm not talking about dinosaurs honey i'm talking way back further back than that um really these they're these little little um creatures called uh amphioxus which is the modern it's a or a lancet that's the modern animal but it's an animal that scientists believe is very similar to um our common the common ancestor that we share uh with invertebrates um because uh basically because of the tracing back the molecular genetics and cells and that animal had no brain it had some cells that would later turn into a brain but in that animal there's no brain but that animal also had no head and it had no eyes and it had no ears and it had really really no senses for the most part it had very very limited sense of touch it had an eye spot for um not for seeing but just for um in training to circadian rhythm to light and dark and it had no hearing it had a vestibular cell so that it could keep upright in the water at the time approx we're talking evolutionary scale here so you know give or take some 100 million years or something but at the time you know what are the vertebrate like when of when a backbone evolved and a brain evolved a full brain that was when a head evolved with sense with sense organs and when um that's when your viscera like internal systems involved so the answer i would say is that um that senses nurse motor neuroscientists people who study the control of motor behavior believe that senses evolved in the service of motor action so the idea is that like what triggered the what triggered what was what was the big evolutionary change what was the big pressure uh that made it useful to have eyes and ears and a visual system and an auditory system and a brain basically and you know and the answer that um is you know commonly entertained right now is that it was predation that when at some point an animal evolved that deliberately ate another animal and this launched an arms race between predators and prey and it became very useful to have senses right so these these little antioxidants these little amphioxy you know don't really have they they don't have an um they're not aware of their environment very much really they um uh and so being able to look up ahead and you know ask yourself you know is that you know should i eat that or will it eat me um is is a very useful thing so the idea um is that sense sense sense data is not there for consciousness it didn't evolve for the purposes of consciousness it didn't evolve for the purposes of experiencing anything um it evolved uh in the cert to be in the service of motor control however maybe it's useful um this is why you know scientists sometimes uh avoid questions about why things evolved that this is what philosophers call this teleology you might be able to say something about how things evolve but not necessarily why we don't really know the why that's all speculation but the y is kind of nice here this the interesting thing is uh that was the first element of social interaction is am i gonna eat you or are you gonna eat me and for that it's useful to be able to see each other sense each other that's kind of fascinating that there was a time when life didn't eat each other or they did by accident right so an amphioxus for example well um it kind of like gyrates in the water and then it plants itself in the sand like a blade of like a living blade of grass and then it just filters uh whatever comes into its mouth right so it is it is eating but it's not actively hunting and when um the concentration of food decreases it the amphioxus can sense this and so it basically wriggles itself randomly to some other spot which probabilistically will have more food than wherever it is so it's not really you know it's not guiding its actions um on the basis of it's not we would say there's no real intentional action um in that in that in the traditional sense speaking of intentional action and if the brain is put if prediction is indeed a core component of the brain let me ask you a question that scientists also hate is uh about free will so how does uh do you think about free will much how does that fit into this into your view of the brain why does it feel like we make decisions in this world this is a hard q a scientists hate this because it's a hard it's a hard question we don't know they're taken aside i think i have free will i think i have taken aside but it it i don't put a lot of stock in my own intuitions or anybody's intuitions about the cause of things right our ex one thing we know about the brain for sure is that the brain creates experiences for us my brain creates experiences for me your brain creates experiences for you in a way that lures you to believe that those experiences actually reveals the way that it works right but it doesn't so so you don't trust your own intuition about not really not really no i mean no but but i am also somewhat persuaded by you know i think dan dennett wrote at one point like um uh you know the philosopher dan dennett wrote at one point that um it it's i can't say it as eloquently as him but it people obviously have free will they are obviously making choices so it's you know and so there is this observation that we're not robots and we can do some things like a little more sophisticated than an amphioxus so um so here's what i would say i would say that your predictions your internal model that's running right now right that your ability to understand the sounds that i'm making and attach them to ideas is based on the fact that you have years of experience knowing what these sounds mean in a particular statistical uh pattern right i mean that's how you can understand the words that are coming out of my mouth right i think we did this once before too didn't we when we were i don't know i would have to access my memory module i think when i was in your glen classic yeah i think we did it just like that actually so bravo wow yeah i have to go look look back to the tape yeah anyways the um the idea though is that your brain is using past experience and it can and it can use past experience in um so it's remembering but you're not consciously remembering it's basically re-implementing prior experiences as a way of predicting what's going to happen next and it can do something called conceptual combination which is it can take bits and pieces of the past and combine it in new ways so you can experience and make sense of things that you've never encountered before because you've encountered something similar to them um and so a brain in a sense is not um just um doesn't just contain information it is information gaining meaning it can create it new information by this generative process so in a sense you could say well that maybe that's that's a source of free will but i think really where free will comes from or the kind of free will that i think is worth having a conversation about is um involves cultivating experiences for yourself that change your internal model when you were born and you were raised in a particular context that your mod your brain wired itself to your surroundings to your physical surroundings and also to your social surroundings so you were handed an internal model basically um but uh when you grow up the more control you have over your where you are and what you do um you can cultivate new experiences for yourself and those new experiences can change your internal model and you can actually um practice those experiences in a way that makes them automatic meaning it makes it easier for the brain your brain to make them again and i think that that is something like what you would call free will you aren't responsible for the model that you were handed that someone you know your your caregivers uh cultivated a model in your brain you're not responsible for that model but you are responsible for the one you have now you can choose you choose what you expose yourself to you choose uh how you spend your time not everybody has choice over everything right but everybody has a little bit of choice um and and so i think that is uh something that i think is arguably called free will yeah there's this like the the ripple effects of the billions of decisions you make early on in life have are so great that uh even if it's not even if it's like all deterministic just the amount of possibilities that are created and then the focusing of those possibilities into a single trajectory uh that somewhere within that that's free will even if it's all deterministic that might as well be of just the number of choices that are possible and the fact that you just make one trajectory to those set of choices seems to be like something like they'll be called free will but it's still kind of sad to think like there doesn't seem to be a place where there's magic in there where it is all just a computer well there's lots of magic i would say so far because we don't really understand uh how all of this is exactly played out at a i mean scientists are working hard and disagree about some of the details under the hood of what i just described but i think there's quite a bit of magic actually and also there's there's also um stochastic firing of neurons don't they they're not purely digital in the sense that there is there's also analog communication between neurons not just digital so it's not just with not just with firing of axons and some of that there's there are other ways to communicate and also um uh there's noise in the system and the noise is there for a really good reason and that is the more variability there is the more potential there is for your brain to be able to be information bearing so um basically you know there are some animals that have clusters of cells the only job is to inject noise you know into their um neural patterns so maybe noise is the source of free will so you can think about you can think about stochasticity or noise as as a source of free will or you can think of of um conceptual combination as a source of free will you can certainly think about um cultivating uh you know you can't reach back into your past and change your past you know people try by psychotherapy and so on but what you can do is change your present which becomes your past right think about that sentence so one way to think about it is that you're continuously this is a colleague of mine a friend of mine said so what you're saying is that people are continually cultivating their past and i was like that's very poetic yes you are continually cultivating your past as a means of controlling your future so you think uh yeah i guess the the construction of the mental model that you use for prediction ultimately contains within it your perception of the past like the way you interpret the past or even just the entirety of your narrative about the past so you're constantly rewriting the story of your past oh boy yeah that's one poetic and also just awe inspiring what about the other thing you talk about you've mentioned about sensory perception as a thing that like is just you have to infer about the sources of the thing that you have perceived through your senses so uh let me ask the another ridiculous question is is anything real at all like how do we know it's real how do we make sense of the fact that just like you said there's this brain sitting alone in the darkness trying to perceive the world how do we know that the world is out there i will be perceived yeah so i don't think that you should be asking questions like that without passing a joint right no for sure yeah i actually did before this so i apologize okay no well that's okay you apologize for not sharing that's okay so i mean here's what i would say what i would say is that the reason why we can be pretty sure that there's a there there is that the the structure of the information in the world what we call statistical regularities in sights and sounds and so on and the structure of the information that comes from your body it's not random stuff there's a structure to it there's a spatial structure and a temporal structure and that spatial and temporal structure wires your brain so an infant brain is not a miniature adult brain it's a brain that is waiting for wiring instructions from the world and it must receive those wiring instructions to develop in a typical way so for example when a newborn is born when a newborn is born when a when a baby is born um the baby can't see very well because the visual system in that baby's brain is not complete the the retina of your eye which actually is part of your brain has to be stimulated with photons of light if it's not the baby won't develop normally to be able to see in in a neurotypical way same thing is true for hearing the same thing is true really for all your senses so the point is that that the physical world the sense data from the physical world wires your brain so that you have an internal model of that world so that your brain can predict well to keep you alive and well and allow you to thrive that's fascinating that the brain is waiting for a very specific kind of uh set of instructions from the world like not not the specific but a very specific kind of instruction yes so you scientists call it expectable input the brain needs some input in order to develop normally and so we're and we are genetically you know we as i say in the book we we have the kind of nature that requires nurture we we can't develop normally without sense input sensory input from the world and from the body and what's really interesting about humans and some other animals too but really seriously in humans is the input that we need is not just physical it's also social we in order for an an infant a human infant to develop normally that infant needs eye contact touch it needs certain types of smells it needs to be cuddled it needs right so um without social input the brain it's that that infant's brain will not wire itself in a neurotypical way and again i would say there are lots of um cultural patterns of caring for an infant it's not like the infant has to be cared for in one way um whatever the social environment is for an infant that it will will be reflected in that infant's internal model so we have lots of different cultures lots of different ways of rearing children and that's an advantage for our species although we don't always experience it that way that is an advantage for our species but if you if you just you know feed and water a baby without all the extra social doodads what you get is a profoundly impaired uh human yeah but nevertheless you're kind of saying that the physical reality has uh has a consistent thing throughout that keeps feeding these set of sensory information that our brains are constructed for but yeah the cool thing though is that if you change the consistency if you change the statistical regularities so prediction error your brain can learn it it's expensive for your brain to learn it and it takes a while to for the brain to get really automated with it but you know you um had a wonderful conversation with david eagleman who just published a book about this yeah and gave lots and lots of really very very cool examples some of which i actually discussed in how emotions were made but not obviously to the extent that he did um in his book which it's a fascinating book and it's but it it speaks to the point that your internal model is always under construction and therefore you always can modify your experience i wonder what the limits are like uh if we can if we put it on mars or if we put in virtual reality or if we sit at home during a pandemic and we spend most of our day on twitter and tick tock like i wonder what where the breaking point like the limitations of the brain's capacity to uh to properly continue wiring itself well i think what i would say is that there are different ways to specify your question right like one way to specify it would be the way that david um phrases it which is can we can we create a new sense like can we create a new sensory modality how hard would that be what are the limits in doing that um and um but another way to say it is what what happens to a brain when you remove some of those statistical regularities right like what happens to a brain what happens to an adult brain when you remove some of the statistical patterns that were there and they're not there anymore you're talking about in the environment or in the actual like you remove eyesight for example or did you well either way i mean basically one way to limit the inputs to your brain are to stay home and protect yourself another way is to put someone in solitary confinement another way is to stick them uh in a nursing home another well not all nursing homes but you know but there are some right which really are some where peop people are somewhat impoverished in the interactions the end this sensory the variety of sensory stimulation that they get another way is that you lose a sense right but the point is i think that you know the human brain really likes variety to to say it in a you know like a pro you know sort of cartesian way you know variety is a good thing um for a brain and um uh there are risks that you take uh when you restrict uh what you expose yourself to yeah you know there's always talk of diversity the brain loves it to the fullest definition and degree of diversity yeah i mean i would say the only thing basically human brains thrive on diversity the only place where we seem to have difficulty with diversity is with each other right but we who wants to eat the same food every day you never would who wants to wear the same clothes every day i mean my husband if you ask him to close his eyes he won't be able to tell you what he's wearing he's just right he'll buy seven shirts of exactly the same style in different colors but they are in different colors right it's not like how would you then explain my brain which is terrified of choice and therefore i wore the same thing every time well you must be getting your diversity well first of all you are a fairly sharp dresser so there is that but um so you're getting some reinforcement progressing the way that you do but well your brain must get diversity in in other words in other places but i think we you know the the so there the two most expensive things your brain can do metabolically speaking is um is move your body um and uh learn something new so novelty that is diversity right comes at a cost a metabolic cost but it's a cost it's an investment that that gives returns and in general people vary in how much they like novelty unexpected things some people really like it some people really don't like it and there's everybody in between but in general we don't eat the same thing every day we don't usually do exactly the same thing in exactly the same order in exactly the same place every day the only place we have difficulty uh with diversity in is in each other and then we we have considerable problems there i would say as a species let me ask uh i don't know if you're familiar with donald hoffman's work about this like questions of reality what are your thoughts of the possibility that the very thing we've been talking about of the brain wiring itself from birth to a particular set of inputs is just a little slice of reality that there is something much bigger out there that we humans with our cognition cognitive capabilities is just not even perceiving that the thing we're perceiving is just the crappy like windows 95 interface onto a much bigger richer set of complex physics that we're not even in touch with well without getting too metaphysical about it i think we know for sure it doesn't have to be the you know crappy version of anything but we definitely have a limited we have we have a set of senses that are limited in very physical ways and we're clearly not perceiving everything there is to perceive that's clear i mean it's just it's not that hard we can't without special why do we invent scientific tools it's so that we can overcome our senses and and experience things that we couldn't otherwise whether they are you know different parts of the uh visual spectrum the light spectrum or um things that are too microscopically small for us to see or too far away for us to see so clearly we're only getting a slice um and that slice you know the interesting or potentially sad thing about humans is that we whatever we experience we think there's a natural reason for experiencing it and we think it's obvious and natural and it must be this way and that all the other stuff isn't important and that's clearly not true many of the things that we think of as natural are anything but we've cr they're certainly real but we've created them they certainly have very real impacts but we've created those impacts and we also know that there are many things outside of our awareness that have have tremendous influence on what we experience and what we do so there's no question that that's true i mean just it's it's um but the extent is how fantastic really the question is how fantastical is it yeah like what you know a lot of people ask me i'm i'm not allowed to say this i think i'm allowed to say this uh i've eaten shrooms a couple times but i haven't gone the full i'm talking to a few researchers and psychedelics it's an interesting scientifically place like what is the portal you're entering when you take psychedelics or another would ask is like dreams whatever so let me tell you what i think which is based on nothing like this is based on my life right so i don't your intuition it's based on my it's based on my i'm guessing now um based on what i do know i would say but i think that well think about what happens so you're running your brain's running this internal model right and it's all outside of your awareness really you see the you feel the products but you don't you don't sense the you have no awareness of the mechanics of it right it's going on all the time um and so one thing that's going on all the time that you're completely unaware of is that um when your brain your brain is basically asking itself figuratively speaking not literally right like how is the scent given the last time i was in this sensory array with this stuff going on in my body and i and that this chain of events which just occurred what did i do next what did i feel next what did i see next it doesn't come up with one answer it comes up with a distribution of it possible answers and then there has to be some selection process and so you have a network in your brain a subnetwork in your brain a population of neurons that helps to choose it's not i'm not talking about a homunculus in your brain or anything silly like that um this is not the soul it's not the center of yourself or anything like that but there is um a a set of neurons that weighs the probabilities uh um um and and helps to select uh or narrow the field okay and that that network is working all the time it's actually called the control network the executive control network or you can call it a fronto parietal because the regions of the brain that make it up or in the frontal lobe and the parietal lobe there are also parts that belong to the subcortical parts of your brain it doesn't really matter the point is that that there is this network and it is working all the time whether or not you feel in control whether or not you feel like you're expending effort doesn't really matter it's on all the time except when you sleep when you sleep it's it's a little bit relaxed and so think about what's happening when you sleep when you sleep the extra the external world recedes the sense data from so basically your model becomes a little bit the tethers from the world are loosened and this network which is involved in you know maybe weeding out unrealistic things is a little bit quiet so use your dreams are really your internal model that's unconstrained by the immediate world except so you can do things that you can't do in real life in your dreams right you can fly like i for example when i fly on my back in a dream i'm much faster than when i fly on my front don't ask me why i don't know when you're laying and you're back in your dream no when i'm in my dream and flying in a dream i am much faster flyer in the air very [Music] i don't think i've flown for many years well you must try it i've i've thought i've uh flown uh i've fallen that's scary yeah but you fl you're talking about like yeah i fly my dreams and i'm way faster right and you're better on my back way faster um now you can say well you know you never flew in your life right it's conceptual combination i mean i've flown in an airplane and i've seen birds fly and i've watched movies of people flying and i know superman probably flies i don't know if he flies faster on his back but he's voice he's out of never he's lying on his front right but yeah but anyways my point is that you know all of this stuff really um all these experiences really become part of your internal model the thing is that when you're asleep your internal model is still being constrained by your body your your brain's always attached to your body it's always receiving sense data from your body you're mostly never aware of it uh unless you run up the stairs uh or or you know uh maybe you um are ill in some way but you're mostly not aware of it which is a really good thing because if you were you know you'd never pay attention to anything outside your own skin ever again like right now you seem like you're sitting there very calmly but you have a virtual whole thing drama right it's like a like a like an opera going on inside your body and so i think that one of the things that happens when people take psilocybin or take uh you know ketamine for example is that the tethers completely are completely removed yeah yeah that's fascinating and then and that's why it's helpful to have a guide right because the guide is giving you sense data to steer that internal model so that it doesn't go completely off the rails yeah i know there's so again that wiring to the other brain that's the guide is at least a tiny little tether exactly yeah let's talk about emotion a little bit if we could emotion comes up often and i have never spoken with anybody who um who has a clarity about emotion from a biological and neuroscience perspective that you do and i'm not sure i fully know how to as a as a i mentioned this way too much but as somebody who was born in the soviet union and romanticizes basically everything talks about love non-stop you know emotion is a i don't know what to make of it i don't know so maybe uh let's just try to talk about it i mean from a neuroscience perspective we talked about a little bit last time your book covers it how emotions are made but what are some misconceptions we writers of poetry we romanticizing humans have about emotion that we should move away from before to think about emotion from both a scientific and an engineering perspective yeah so there is a common view of emotion in the west the caricature of that view is that um you know we have an inner beast right your limbic system your your inner lizard um we have an inner beast and that comes baked in to the brain at birth so you've got circuits for anger atmosphere it's interesting that they all have english names these circles but um that that and they're there and they're triggered by things in the world and um then they cause you to do and say and you know so when your fear circuit is triggered you widen your eyes you gasp your heart rate goes up you prepare to flee or to freeze and these are these are modal responses they're not the only responses that you give but on average they're the prototypical responses that's the view and um that's the view of emotion in the law that's the view you know that emotions are these profoundly unhelpful things that are obligatory kind of like reflexes the problem with that view is that it doesn't comport to the evidence um and it doesn't really matter the evidence actually lines up beautifully with each other it just doesn't line up with that view and it doesn't matter whether you're measuring people's faces facial movements or you're measuring their body movements or measuring their peripheral physiology or you're measuring their brains or their voices or whatever pick any any output that you want to measure and you know any system you want to measure and you don't really find strong evidence for this and i say this as somebody who who not only has reviewed really thousands of articles and run you know big meta analyses which are statistical summaries of of published papers but also as someone who has sent teams of researchers to small-scale cultures you know remote cultures which are very different from urban large-scale cultures like ours and one culture that we visited and i say we euphemistically because i i myself didn't go because i only had two research permits and i gave them to my students because i felt like it was better for them to have that experience and more formative for them to have that experience but i was in contact with them every day by satellite phone and this was um to visit the um hadza hunter-gatherers in tanzania who are not um an ancient people they're a modern culture but they live in circumstances um hunting and foraging circumstances that um are very similar in similar conditions to our ancestors uh hunting gathering ancestors when expressions of emotion were supposed to have evolved at least by one view of okay so i you know for many years i was sort of struggling with um this set of observations right which is that i feel emotion and i see i perceive emotion in other people but scientists can't find a single marker a single biomarker not a single individual measure or pattern of measures that will can predict how someone what kind of emotional state they're in how could that possibly be how how can you possibly make sense of those two things and through a lot of reading and a lot of and immersing myself in different literatures i came to the hypothesis that the brain is constructing these instances out of more basic ingredients so when i tell you that the brain when i suggest you that what your brain is doing is making a prediction and it's asking itself figuratively speaking the last time i was in this situation and this you know physical state what did i do next what did i see next what did i hear next it's basically asking what in my past is similar to the present things which are similar to one another are called a category a group of things which are similar to one another as a category and a mental representation of a category is a concept so your brain is constructing categories or concepts on the fly continuously so you really want to understand what a brain is doing you don't using machine learning like classification models is not going to help you because the brain doesn't classify it's doing category construction and the categories change or you could say it's doing concept construction it's using past experience to conjure a concept which is a prediction and if it's using past experiences of emotion then it's constructing an emotion concept your concept will be the content of it is ism changes depending on the situation that you're in so for example if your brain uses past experiences of anger that you have learned either because somebody labeled them for you taught them to you you observed them in movies and so on in one situation could be very different from your concept of for anger than another situation and this is how anger instances of anger are what we call a population of variable instances sometimes when you're angry you scowl sometimes when you're angry you might smile sometimes when you're angry you might cry sometimes your heart rate will go up it will go down it will stay the same it depends on what action you're about to take because the way predict and i should say the idea that physiology is yoked to action is a very old idea in in uh the study of the peripheral nervous system that's been known for really decades and so if you look at what the brain is doing if you just look at the anatomy and you what here's the hypothesis that you would that you would come up with and i can go into the details i've published these details in in scientific papers and they also appear somewhat in how emotions are made my first book they are not in the you know seven and a half lessons because that book is is really not pitched at that level of explanation right it's just giving it's really just a set of little essays um but the evidence but what i'm about to say is actually based on on on scientific evidence when your brain begins to make form a prediction the first thing it's doing is it's making a prediction of how to change the internal systems of your body your heart your cardiovascular system the control of your heart control of your lungs right a flush of of cortisol which is not a stress hormone it's a hormone that gets glucose into your bloodstream very fast because your brain is predicting you need to do something metabolically expensive and so so either that means either move or learn okay and so your brain is preparing your body the internal systems of your body to execute some actions to move in some way and the and then it infers based on those motor predictions and what we call visceral motor predictions meaning the the the changes in the viscera that your brain is preparing to um to execute um your brain makes an inference about what you will sense based on those motor movements so your experience of the world and your experience of your own body are a consequence of those predictions those concepts when your brain makes a concept for emotion it's constructing an instance of that emotion and that is how emotions are made and those concepts load in the predictions that are made include contents inside the body contents outside the body i mean it includes other humans so just this construction of a concept includes the variables that are much richer than just some sort of um simple notion yeah so our colloquial notion of a concept where um you know um where i say well what's the concept of a bird and then you list a set of features off to me that's that's people's understanding you know typically of what a concept is but if you go uh into the literature in um cognitive science what you'll see is that the way that scientists have understood what a concept is has really changed over the years so people used to think about a concept as um philosophers and scientists used to think about a concept as a dictionary definition for a category so there's a set of things which are similar out in the world and um your concept for for that category is a dictionary definition of the features right the necessary insufficient features of that of those instances so for a bird um you know would be wings feathers right a beak yeah it flies whatever okay um that's called the classical category and scientists discovered observed that actually not all instances of birds have feathers and not all instances of birds fly and so the idea was that you don't have a single representation of necessary and sufficient features stored in your brain somewhere instead what you have is a prototype a prototype meaning um you still have a single representation for the category one um but the features are like of the most typical instance of the category or maybe the most frequent instance but not all instances of the category have all the features right they they have some graded similarity to the prototype and then uh you know what um i'm gonna like incredibly simplify now a lot of work to say that then a series of experiments were done to show that in fact what your brain seems to be doing is coming up with a single exemplar or instance of the category and reading off the um features when i ask you for the concept so if we were in a pet store and i asked you what are the features of a bird tell me the concept of bird you would be more likely to give me features of a good pet and if we were in a restaurant you would be more likely you know like a budgie right or a canary if we were in a restaurant you would be more likely to give me the features of a bird that you would eat like a chicken and if we were in a park you'd be more likely to give me uh in this country uh you know the features of a sparrow or a robin whereas if we were in south america you would probably give me the features of a peacock because that's more common or it's or it is more common there than here that you would see a peacock in such circumstances so the idea was that really what your brain was doing was conjuring a concept on the fly that meets the function that the category is being put to okay yep okay then people started studying ad hoc concepts meaning um concepts that where the instances don't share any feat any physical features but the function of the instances are the same so for example think about all the things that can protect you from the rain what are all the things that can protect you from the rain uh umbrella uh like this apartment right um your car not giving a damn like like a like a mindset yeah right right so the idea is that the function of the instances is the same in a given situation even if they look different sound different smell different this is called an abstract concept or a conceptual concept now the really cool thing about conceptual categories or conceptual concept yes conceptual category a conceptual as a category of things that are held together by a function which is called an abstract concept or a conceptual category because the things don't share physical features they share functional features there are two really cool things about this one is that's what darwin said a species was so darwin is known for discovering natural selection but the other thing he really did which was really profound which he's less celebrated for is understanding that all biological categories have inherent variation inherent variation darwin wrote in the origin of species about before darwin's book a species was thought to be a classical category where all the instances of dogs were the same had exactly the same features and any variation from that perfect platonic instance was considered to be error and darwin said no it's not error it's meaningful nature selects on the basis of that variation the reason why natural selection is powerful and can exist is because there is variation in a species and in dogs we talk about that variation in terms of the size of the dog and the uh amount of fur the dog has and the color and the how long is the tail and how long is this snout in humans we talk about that variation in all kinds of ways right including in cultural ways so that's one thing that's really interesting about conceptual categories is that darwin is basically saying a species is a conceptual category and in fact if you look at modern debates about what is a species you can't find anybody agreeing on what the criteria are for a species because they don't all share the same genome we don't all share we don't there isn't a single human genome there's a population of genomes but they're variable it's not unbounded variation but they are variable right and the other thing that's really cool about conceptual categories is that um they are the categories that we use to make civilization so think about money for example what are all the physical things that make something a currency is there any physical feature that all the currencies in all the worlds that's ever been used by humans share well certainly right but uh but what what is it uh is it definable you know so it's getting to the point that you're because you're making it function it's the function right function it's that we trade it for material goods and that and we have to agree right we all impose on whatever it is salt barley little shells big rocks in the ocean that can't move bitcoin pieces of plastic mortgages which are basically a promise of something in the future nothing more right all of these things we impose value on them and we all agree that we can exchange them for material goods yeah and uh yes that's bril by the way you're attributing some of that to darwin that he thought no i'm no i'm saying that because it's a brilliant view of what a species is is the function yeah what i'm saying is that what darwin darwin really talked about variation in um so if you read for example the biologist ernst mayer who was an evolutionary biologist and then when he retired became a historian and philosopher of biology and his suggestion is that darwin darwin did talk about variation he vanquished what's called essentialism the idea that there's a single set of features that define any species and um out of that grew um really discussions of the function you know like some of the functional features that species have like they can reproduce uh off they can have offspring the individuals of a species can have offspring it turns out that's not a perfect uh you know that's not a perfect uh criterion to use but it's a functional criterion right so what i'm saying is that in cognitive science people came up with the idea they discovered the idea of conceptual categories or ad hoc concepts these concepts that can change based on the function they're serving right and um uh that it's there darwin it's in darwin and it's also in the philosophy of social reality you can the way that philosophers talk about social reality just look around you i mean we impose we're treating a bunch of things as similar which are physically different and sometimes we take things that are physically the same and we treat them as separate categories but it feels like the number of variables involved in that kind of categorization is nearly infinite no i don't think so because there is a physical constraint right like you and i could agree that um we can fly in real life but we can't that's a physical that's a physical constraint that we can't break right you and i could agree that we could walk through the walls right but we can't we could agree that we could eat glass but there's a lot of constraints but yeah we could agree that the virus doesn't exist and we don't have to wear masks right yeah but you know physical reality still holds the trump card right but still there's a lot of card well pun completely unattended but there you go that's a predicting brain for you um uh but but there's a tremendous amount of leeway yes yeah that's the point so what i'm saying is that emotions are like money basically they're they're like money they're like countries they're like um kings and queens and presidents they're like everything that we construct that we impose meaning on we take these physical signals and we give them meanings that um they don't otherwise have by their physical nature and because we agree yeah they have that function but the the beautiful thing so maybe unlike money i love this similarity is it it's not obvious to me that this kind of emergent agreement should happen with emotion because our experiences are so different for each of us humans and yet we kind of converge well in a culture we converge but not across cultures there are huge huge differences there are huge differences in what what concepts exist what their um what they look like um so what i would say is that they feel like what what we're doing with our young children as we as their brains become wired to their physical and their social environment right is that we are curating for them we are bootstrapping into their brains a set of emotion uh concepts that's partly what they're learning and we curate those for infants just the way we curate for them what is a dog what is a cat what is a truck we sometimes explicitly label and we sometimes just use mental words when you know your kid is you know throwing cheerios on the floor instead of eating them or your kid is crying when you know she won't put herself to sleep or whatever you know we use mental words and um a word is this words with for infants words are these really special things that they help infants learn abstract categories there's a huge literature showing that children can take things that don't look infants like infants really young infants pre-verbal infants can take if you label if i say to you and you're an infant okay so i say lex lexi this yeah is a bling yeah and i put it down and the bling makes a squeaky noise and then i say unless he's excited by the way this is a bling and i put it down and it makes a squeaky noise and then i say lexi this is a bling you as young as four months old will expect this to make a noise a speaking noise and if you don't if it doesn't you'll be surprised because it violated your expectation right i'm building for you an internal model of a bling yeah okay infants can do this really really at a young age and so there's no reason to believe that they couldn't learn emotion categories and concepts in the same way and in in one and what happens when you go to a new culture when you go to a new culture you have to do what's called emotion acculturation so my colleague bacia mosquita in belgium studies emotion acculturation she studies how when people move from one culture to another how do they learn the emotion concepts of that culture how do they learn to make sense of their own internal sensations and also the movements you know the rays of an eyebrow the tilt of a head how do they learn to make sense of cues from other people using concepts they don't have but have to make on the fly so that's the difference between cultures let me uh open another door i'm not sure i want to open but difference between men and women is there um difference between the emotional lives of those two categories of biological systems so here's what i would say you know we did a series of studies um uh in the 1990s where we asked men and women to tell us about their emotional lives and women described themselves as much more emotional than men they believed that they were more emotional than men and men agreed women are much more emotional than men okay and then we gave them little handheld computers these were little hewlett-packard computers they fit in the palm of your hand a couple of pen they weighed a couple of pounds so this was like pre-palm pilot even like this was you know 1990s and like early and um we um asked them we would you know ping them like 10 times a day and just ask them to report how they were feeling which is called experience sampling so we experience sampled and and then at the end and then we looked at their reports and we found is that men and women basically didn't differ and there were some people who were really had many more instances of emotion so they were you know um they were treading uh water in a tumultuous sea of emotion and then there were other people who were like floating tranquilly you know in a lake it was really not perturbed very often and and everyone in between but there were no difference between men and women and the really interesting thing is at the end of the sampling period we asked people um so reflect over the past two weeks and tell it so you know we've been now pinging people like again and again and again right so tell us how emotional do you think you are no change from the beginning so men and women believe that they are they believe that they are different and when they are looking at other people they make different inferences about emotion if a man if a man is scowling like if you and i were together and some so somebody's watching this okay and um yeah hey when you look at the camera um if you and i make exactly the same set of facial movements when people look at you both men and women look at you they are more likely to think oh he's reacting to the situation and when they look at me they'll say oh she's having an emotion she's you know yeah and i wrote about this actually um uh right before the 2016 election you know what maybe i could confess let me try to carefully confess but you are really gonna yeah that i'm that when i that there is an element when i see hillary clinton that there was something annoying about her to me and i just that feeling and then i tried to reduce that to what what is that because i think the same attributes that are annoying about her when i seen other people wouldn't be annoying so i was trying to understand what is it because it it certainly does feel like that concept that i've constructed in my mind well i'll tell you that i think well let me just say that um that that what you would predict about for example the performance of the two of them in the debates and i wrote an op-ed for the new york times actually um before the second debate and it it played out really pretty much as i thought that it would on based on research it's not like i'm like a great fortune teller or anything it's just i was just applying the research which was that when a woman um a woman's people make internal attributions it's called they infer that the facial movements and body posture and vocalizations of a woman reflect her inner state but for men they're more likely to assume that they reflect his response to the situation it doesn't say anything about him it says something about the situation he's in that's brilliant now for the thing that you are that you were describing about hillary clinton um i think a lot of people experienced but it's also in line with research which shows and and particularly research actually on um in about teaching evaluations is one place that you really see it where the expectation is that a woman will be nurturant and that a man there's just no expectation for him to be nurturing so he's you know if he is nurturant he gets points um if he's not he gets points right they're just different points right whereas for a woman especially a woman who's an authority figure she's really in a catch-22 right because if she's serious she's a and if she's empathic uh then she's weak right that's brilliant i mean one of the bigger questions to ask here so that's one example where our con construction of concepts gets right but remember you're in trouble but so remember i said science is a science and philosophy are like tools for living so i learned recently that if you ask me what is my intuition about what regulates my eating i will say carbohydrates i love carbohydrates i love pasta i love bread i love i just love carbohydrates but actually research shows and it's beautiful research i love this research because it so violates my own like deeply deeply held beliefs about myself that most animals on this planet who have been studied and there are many actually eat to regulate their protein intake so you will overeat carbohydrates if you in order to get enough protein and these this research has been done with human very beautiful research with humans with crickets with like you know bonobo i mean just like all these different animals not bonobos but i think like baboons um now that i have no intuition about that and i even now as i regulate my eating i don't i still i just have no intuition it just i can't i can't feel it what i feel is only about the carbohydrates it feels like you're regulating around carbohydrates not the protein yeah but in fact actually what i am doing if i am like most uh animals on the planet i am regulating around proteins so knowing this what do i do i correct my behavior to eat to to actually deliberately try to focus on the protein that this is the idea behind bias training right like if you um i also did not experience hillary clinton as the warmest candidate however you can use consistent science since the consistent scientific findings to organize your behavior that doesn't mean that rationality is the absence of emotion because sometimes emotion or scent anything feelings in general not the same thing as emotion um that's another topic um but you know our our source of of information and their wisdom and helpful so i'm not saying that but what i am saying is that if you have a deeply held belief and the evidence shows that you're wrong then you're wrong it doesn't really matter how confident you feel you that confidence could be also explained by science right so it would be the same thing as if i regardless of whether someone is like charlie baker right regardless of whether somebody is a republican or a democrat if that person has a record that you can see is consistent with what you believe then that is information that you can act on yeah and and then so try to i mean this is kind of what empathy is in open-mindedness is try to um consider that the set of concepts that your your brain has constructed through which you are now perceiving the world is not painting the full picture i mean this is now true for basically ever it doesn't have to be men and women it could be basically the prism through which we pursue actually the political discourse right absolutely so so here's what i would say um the you know there are people who scientists who will talk to you about cognitive empathy and emotional empathy and i i prefer to think of it i think the evidence is more consistent with what i'm about to say which is that your brain is always making predictions using your your own past experience and what you've learned from you know books and movies and other people telling you about their experiences and so on and if your brain cannot make a concept to make sense of those anticipate what those sense data are and make sense of them you will be experientially blind so you know when i'm giving lectures to people i'll show them like a blobby black and white image and they're experientially blind to the image they can't see anything in it and then i show them a photograph and then i show them the image again the blobby image and then they see actually an object in it but the art but the image is the same yeah it's there they're actually adding their predictions now are adding right or anything for example anybody who's learned a language uh a second language after their first language also has this experience of um things that initially sound like sounds that they can't quite make sense of eventually come to make they eventually come to make sense of them and in fact there are really cool examples of people who are like born blind because they have cataracts or um they have corneal damage so that no light is reaching the brain and then they have an operation and then light reaches the brain and they can't see for days and weeks and sometimes years they have they are experientially blind to certain things so what happens with empathy right is that your brain is making a prediction and if it doesn't if it doesn't have the capacity to um make it doesn't if you don't share if you're not similar remember you mean you know categories are instances which are similar in some way if you are not similar enough to that person you will have a hard time making a prediction about what they feel you will be experientially blind to what they feel in the united states children of color are under prescribed medicine by their physicians this is been documented it's not that the physicians are racist necessarily but they might be experientially blind the same thing is true of male physicians with female patients i could tell you some hair-raising stories really that where people die as a consequence of a physician making the wrong inference the wrong prediction because of being experientially blind so we are you know empathy is not um it's not magic it's we make inferences about each other about what each other's feeling and thinking in this culture more than there are some cultures where you know people have what's called opacity of mind where they will make a prediction about someone else's actions but they're not inferring anything about the internal state of that person but in our culture we're constantly making inferences what is this person thinking what is and we're not doing it necessarily consciously but it's doing it really automatically using our predictions what we know and if you expose yourself to information which is very different from somebody else i mean really what we have is we have different cultures in this in this country right now that are there are a number of reasons for this i mean part of it is i don't know if you saw the social dilemma the the netflix um uh part about it yeah it's a great it's really great um documentary and uh about what social networks are doing to our society yeah yeah but you know nothing no phenomenon has a a simple single cause there are multiple small causes which all add up to a perfect storm that's that's just you know how most things work and so the fact that machine learning algorithms are serving people up information on social media that is consistent with what they've already viewed and making you know um is part of the reason that you have these silos but it's not the only reason why you have these silos i think there are other there are other things afoot that uh enhance um people's inability to even have a decent conversation yeah i mean okay so so many things you said are just brilliant so the experiment experiential blindness but also from my perspective like i i preach and i try to practice empathy a lot and something about the way you've explained it makes me almost see it as a kind of exercise that we should all do like to train like to add experiences to the brain to expand this capacity to predict more effectively absolutely so like what like what i do is kind of like a method acting thing which is i imagine what the life of a person is like you know just think i mean this is something you see with black lives matter and uh police officers it feels like they're both uh not both but i have because martial arts and so on i have a lot of friends who are cops they don't necessarily have empathy or visualize the experience of the other certainly currently unfortunately people aren't doing that with police officers they're not imagining they're not empathizing or putting themselves in the shoes of a police officer to realize how difficult that job is how dangerous it is how difficult it is to maintain calm and under so much uncertainty all this kind of thing you know but there's more there's even that's all that's true but i think that there's even more there's even more to be said there i mean like from a predicting brain standpoint there's even more that can be said there so i don't know if you want to go down that path or you can strike on empathy but i will also say that one of the things that i was most gratified by i still am receiving you know it's been three more than three and a half years since how emotions are made came out and i'm still receiving daily emails from people right so that's gratifying but one of the most gratifying emails i received was from police officer in texas who told me that he thought that how motions are made contained information that would be really helpful to resolving some of these difficulties and he hadn't even read my op-ed piece about when is a gun not a gun and you know like using the what we know about the science of perception from predict from a prediction standpoint like the brain is a predictor to understand a little differently what might be happening in these circumstances so there's there's a real what's hard about it's hard to talk about because everyone gets mad at you when you talk about this like you know and um there is a way to understand this which has profound empathy for the suffering of people of color and that definitely is in line with black lives matter at the same time as understanding the really difficult situation that police officers find themselves in and i'm not talking about this bad apple or that bad apple i'm not talking about police officers who are necessarily shooting people in the back as they run away i'm talking about the cases of really good well-meaning cops who have the kind of predicting brain that everybody else has they're in a really difficult situation that i think both they and the people who are harmed don't realize like they just the the way that these situations are constructed i think it's just there's a lot to be said there i guess is what i wanted is there something we can try to say in a sense like what i'm from the perspective of the predictive brain which is a fascinating perspective uh to take on this you know the all the protests are going on there seems to be a concept of a police officer being built no i think that police i think that concept is there but it's is gaining strength so it's being re-um i mean yeah it is sure it is there but i think yeah for sure i think that that's right i think that there's um there's a shift in the stereotype of what i would say is a stereotype there's a stereotype of of uh black man in this country that's always in movies and television not always but like largely um that many people watch i mean you know you think you're watching a 10 o'clock drama and all you're doing is like kicking back and relaxing but actually you're having certain predictions reinforced and others not and what's happening what's happening now with police is the same thing um that there are certain stereotypes of a police officer that are being abandoned and other stereotypes that are being reinforced by by what you see happening all i'll say is that if you remember i mean there's a lot to say about this really that you know regardless of whether it makes people mad or not i mean i just i the science is what it is um just remember what i said the brain is makes predictions about internal changes in the body first and then motor it starts to prepare motor action and then it makes a prediction about what you will see and hear and feel based on those actions okay so it's also the case that we didn't talk about is that sensory sampling like your brain's ability to sample what's out there is yoked to your heart rate it's yoke to your heartbeats there are certain phases of the heartbeat where it's easier for you to see what's happening in the world than in others and so if your heart rate goes through the roof you will be less like you will be more likely to just go with your prediction and not correct based on what you what's out there because you're actually literally not seeing as well or you will see things that aren't there basically is there something that we could say in by way of advice for when this episode is released in the in the chaos of uh emotion sorry i don't know about a term that's just flying around on social media what's um well i actually think it is it is emotion in the following sense you know and it sounds a little bit like it sounds a little bit like artificial when i and the way i'm about to say it but i really think that this is what's happening you know one thing we haven't talked about is you know brains evolved didn't evolve for you to see they didn't evolve for you to hear they didn't evolve for you to feel they evolved to control your body that's why you have a brain you have a brain so they control your body and the metaphor the there's a the scientific term for predictively controlling your body is allostasis your brain is making um is attempting to it's tempting to anticipate the needs of your body and meet those needs before they arise so that you can act as you need to act and the metaphor that i use is a body budget you know your brain is running a budget for your body it's not budgeting money it's budgeting glucose and salt and water and instead of having you know one or two bank accounts it has gazillions there are all these systems in your body that have to be kept in balance and it's monitoring very closely it's making predictions about like when is it good to spend and when is it good to save and what would be a good investment and am i going to get a return on my investment whenever people talk about reward or reward prediction error or anything to do with reward or punishment they're talking about the body budget they're talking about your brain's predictions about whether or not there will be a deposit or withdrawal so when you when your brain is running a deficit in your body budgets you have some kind of metabolic imbalance you experience that as discomfort you experience that as distress when your brain when things are chaotic you can't predict what's going to happen next so i have this absolutely brilliant scientist working in my lab his name is um jordan terrio and he's published this really terrific paper on um a sense of should like why do we have social rules why do we you know adhere to social norms it's because if i make myself predictable to you then you are predictable to me and if you're predictable to me that's good because that that is less metabolically expensive for me novelty or unpredictability at the extreme is expensive and if it goes on for long enough what happens is first of all you will feel really jittery and antsy which we describe as anxiety it isn't necessarily anxiety it could be just something is not predictable and you are experiencing arousal because the chemicals that help you learn increase your feeling of arousal basically but if it goes on for long enough you will become depleted you will start to feel really really really distressed so what we have is a culture full of people right now who are their body budgets are just decimated yeah and there's a tremendous amount of uncertainty when you talk about it as depression anxiety it makes you think that it's not about your metabolism that it's not about your body budgeting that it's not about getting enough sleep or about eating well or about making sure that you have social connections um it's you know it's you think that it's something separate from that but depression anxiety are just a way of being in the world they're a way of being in the world when things aren't quite right with your predictions that's such a deep way of thinking like the the brain is maintaining homeostasis it's actually allostational stasis i'm sorry uh and it's it's constantly making predictions and metabolically speaking it's very costly to make novel like constantly be learning to making adjustments and then over time there's you know there's a cost to be paid if you're just yeah in in in a place of chaos where there's constant need for adjusting and learning and experience novel things and so part of the problem here there are a couple of things like i said you know it's a perfect storm there isn't a single cause right there are multiple cause multiple things that combine together it's a complex it's a complex system multiple things part of it is that um people are they're they're metabolically encumbered and they're distressed and in order to try to have empathy for someone who is very much unlike you you have to forage for information you you have to explore information that is novel to you and unexpected and that's expensive and at a time when people feel what do you do when you are running a deficit in your bank account you stop spending what does it mean for a brain to stop spending a brain stops moving very much stops moving the body and it stops learning it just goes with its internal model brilliantly put yep so empathy requires to have empathy for someone who is unlike you yeah requires learning and practice you're foraging for information i mean it is something i talk about in my in the book in seven and a half lessons about the brain i think it's really important it's hard but it's hard i think it's you know it it's hard for people to have to be curious about views that are unlike their own when um when they feel so encumbered and i'll just tell you i had this epiphany really i was listening to robert reich's the system he was talking about oligarchy versus democracy so oligarchy is where very wealthy people like extremely wealthy people shift power so that they become even more wealthy and even more insulated and from the you know the pressures of the common person um it's actually the kind of system that leads to the collapse of civilizations if you believe jared diamond just say that but anyways i'm listening to this and i'm listening to him describe in fairly decent detail how the ceos of these companies there's been a shift in what it means to be a ceo and not not being no longer being a steward of the community and so on but like in the 1980s it sort of shifted to this other model of being like an oligarch and he's talking about how you know it used to be the case that um that ceos uh made like 20 times uh what their um their employees made and now they make about 300 times on average what their employees made so where did that money come from it came from the pockets of the employees and they don't they don't know about it right no one knows about it they just know they can't feed their children they can't pay for health care they can't take care of their family and they worry about what's going to happen to their you know they're living like you know months a month basically any one big bill could completely you know put them out on the street so there are a huge number of people living like this so all they what their experience they don't know why they're experiencing it so it's and then someone comes along and gives them a narrative yeah well somebody else butted in line in front of you and that's why you're this way that's why you experience what you're experiencing just for a minute i was thinking i had deep empathy for people who have beliefs that are really really really different from mine but i was trying really hard to see it through their eyes yeah and did it cost me something metabolically i'm sure yeah i'm sure but you had something in the gas tank well i in order to allocate that i mean that's the question is like where did you you what resources did your brain draw on in order to actually make that effort well i'll tell you something honestly lex i don't have that much in the gas tank right now [Laughter] right so uh i i am surfing the stress that you know stress is just what is stress stress is your brain is preparing for a big metabolic outlay and it just keeps preparing and preparing and preparing and preparing you as a professor you as a human both right it's a for me this is a moment of existential crisis as much as anybody else democracy all of these things so in many of my roles so well i guess what i'm trying to say is that um i get up every morning and i exercise i run i row i lift weights right you exercise in the middle of the day i saw your like yeah you know daily yeah i hate it actually you love it right you get it no i hate it i hate it but i do it religiously yeah why because it's a really good investment it's an expenditure that is a really good investment and so when i was exercising i was listening to the book and when i realized the insights that i was sort of like playing around with like is this does this make sense does this make sense i didn't immediately plunge into it i basically wrote some stuff down i set it aside and then i did what i i prepared myself to make an expenditure i don't know what you do before you exercise i always have a protein shake always have a protein shake because i need to fuel up before i make this really big expenditure and so i did the same thing i didn't have a protein drink but i um but i i did the same thing and fueling up can mean lots of different things it can mean talking to a friend about it it can mean um you know it can it can mean get making sure you get a good night's sleep before you do it it can mean lots of different things but i i guess i i think we have to do these things i uh yeah that this i'm gonna re-listen to this conversation several times this is brilliant uh but i do i do think about you know i've encountered so many people that can't possibly imagine that a good human being can vote for donald trump and i've also encountered people that can't imagine that an intelligent person can possibly vote for a democrat and i i look at both these people many of whom are friends and uh let's just say after this conversation i can see as they're predicting brains not willing to invest the resources to empathize with the other side and i think you have to in order to be able to like to see the obvious common humanity in us i don't know what the system is that's creating this division we can put it like you said it's a perfect storm it might be the social media might i don't know what the hell i think it's a bunch of things i think it's just there's an economic system which is disadvantaging large numbers of people there's uh a use of social media like if you you know if i had to orchestrate or architect a system that would screw up a human body budget it would be the one that we live in you know we don't sleep enough we eat pseudo food basically we are on social media too much which is full of ambiguity which is really hard for a human nervous system right really really hard like ambiguity with no context to predict it i mean it's like really and then you know there are the economic concerns that affect large swaths of people in this country i mean it's really you i'm not saying everything is reducible to metabolism not everything is reducible to metabolism but there if you combine all these things together it's helpful to think of it that way then somehow it's also uh somehow reduces the entirety of the human experience the same kind of obvious logic like we should exercise every day in the same kind of way we should uh we should empathize every day yeah you know there are these really wonderful wonderful programs for um for teens and um sometimes also for parents of people who've lost children in in wars and in conflicts in political conflicts where they go to a bucolic setting and they talk to each other about their experiences and um miraculous things happen you know so um uh you know it's easy to uh it's easy to sort of shrug this stuff off as kind of pollyanna-ish you know like what's this really gonna do but um you have to think about when my daughter went to college i i gave her advice i said uh try to be around people who let you be the kind of person you want to be you were back to free will you have a choice you have a choice it might seem like a really hard choice it might seem like a unimaginably difficult choice do you have a choice do you want to be somebody who is wrapped in in fury and agony or do you want to be somebody who extends uh a little empathy to somebody else and in the process maybe learn something curiosity is the thing that it protects you curiosity is the thing it's curative curiosity on social media the thing i recommend to people um at least that's the way i've been approaching social media i i don't it doesn't seem to be the common approach but i basically uh give love to people who seem to also give love to others so it's the same similar concept of surrounding by yourself by the people you want to become and i ignore sometimes block but just ignore i don't i don't add aggression to people who are just constantly full of aggression and negativity and toxicity there's a certain desire when somebody says something mean to to um to say something um to you know say why or try to alleviate the meanness and so on but what you're doing essentially is you're and you're you're now surrounding yourself by that group of folks that have that negativity so even just the conversation so i you know i i think it's just so powerful to uh to put yourself amongst people who are yeah who whose basic mode of interaction is kindness because uh i mean i don't know what it is but maybe i'm just it's the way i'm built is that to me is energizing for the gas tank of that that i can pull to for sure when i start reading the rise and fall of the third reich and start thinking about nazi germany i can empathize with everybody involved i can start to think make these difficult uh like thinking that's required to understand our little planet earth well there is research to back up what you said there's research that's consistent with your intuition there you know that there's research that shows that being kind to other people doing something nice for someone else is like making a deposit to some extent you know because i think um [Music] making a deposit not only in their body budgets but also in yours like people feel good when they do good things for other people you know we are social animals we regulate each other's nervous systems for better and for worse right the best thing for a human nervous system is another human and the worst thing for a human nervous system is another human so you decide do you want to be somebody who makes people feel who who who makes people feel better or do you want to be somebody who causes people pain and we are more responsible for one another than we might like or then me might want but remember what we said about social reality you know social reality so you you you know there are lots of different cultural uh norms about uh you know independence or or you know collective you know nature of people but the fact is we have socially dependent nervous systems we evolved that way as a species and in this country we prize individual rights and freedoms and that is a dilemma that we have to grapple with and we have to do it in a way if we're going to be productive about it we have to do it in a way that um requires engaging with each other and which is what i understand the you know the founding members of this country uh intended beautifully put let me ask a few final silly questions so one we talked a bit about love but let me it's it's fun to ask somebody like you who can effectively from at least neuroscience perspective disassemble some of these romantic notions but what do you make of romantic love why do human beings seem to fall in love at least at least a bunch of 80s hair bands have written about it uh is that a nice feature to have is that a bug what is it well i i'm really happy that i fell in love i wouldn't want it any other way but i would say is that you the person speaking or the neuroscientist well i me that's me the person speaking but uh i would say as a neuroscientist babies are born not able to regulate their own body budgets because their brains aren't fully wired yet when you feed a baby when you cuddle a baby when you everything you do with a baby impacts that baby's body budget and helps to wire that baby's body budget has to wire that baby's brain to manage eventually her own body budget to some extent that's the basis biologically of attachment humans evolved as a species to be socially dependent meaning you cannot manage your body budget on your own without a tax that eventually you pay many years later in terms of some metabolic illness right loneliness when you break up with someone that you love or you lose them right it you feel like it's going to kill you but it doesn't but loneliness will kill you it will kill you approximately you know what is it seven years earlier i can't remember exactly the exact number it's it's actually in the web notes to um seven and a half lessons but um social isolation loneliness will kill you earlier than you would otherwise die and the reason why is that you're not you didn't evolve to manage your nervous system on your own and when you do you pay a little tax and that tax accrues very slightly over time over a long period of time so that by the time you're in you know middle aged or a little older you are more likely to die sooner from some metabolic illness from heart disease from diabetes from depression um you're more likely to develop alzheimer's disease i mean it's the it you know it takes a long time for that tax to accrue um but it does so yes i think it's a good thing for people to um to fall in love but i think the funny view of it is that uh it's clear that humans need the social attachment to uh what is it manage their nervous system as as as you're describing and the reason you want to stay with somebody for a long time it's so you don't have is the novelties very costly for uh for well now you're mixing now you're mixing things now you're you know no you have to decide whether but what i would say is when you lose someone you love you um it feels like you've lost a part of you and that's because you have you've lost someone who was contributing to your body budget we are the caretakers of one another's nervous systems like it or not and out of that comes very deep feelings of attachment some of which are romantic love are you afraid of uh your own mortality we two humans sitting here yeah do you think do you ponder your immortality i mean you're somebody who thinks about your brain a lot it seems one of the more um terrifying or i don't know i don't know how to feel about it but it seems to be one of the most definitive aspects of life is that it ends it's a complicated answer but i think the best i can do in a short snippet would be to say for a very long time i did not fear my own mortality i feared the i feared pain and suffering so that that's what i feared i feared being harmed or dying in a way that would be painful um but i didn't fear having my life be over now as a mother i i think i i have fear i fear dying before my daughter is um ready to be without me that's what i fear it's that's that's really what i fear and frankly honestly i fear my husband dying before me much more than i fear my own death there's that love and social attachment again yeah because i know i it's i know it's just gonna i'm gonna feel like i wish i was dead yeah a final question about life uh what do you think is the meaning of it all what's the meaning of life yeah i think that there isn't one meaning of life there's like many meanings of life and you know you use different ones on different days but for me depending on the day depending on the day but for me i would say um sometimes the meaning of life is to understand to make meaning actually the meaning of life is to make meaning um sometimes it's that sometimes it's to um leave the world just slightly a little bit better than it like the johnny appleseed view you know sometimes um the meaning of life is um to um you know like clear the path for my daughter or for my students you know it's to you know so sometimes it's that and sometimes it's just um you know like you know your moments where you're looking at the sky or you're you know by the ocean or sometimes for me it's even like i'll see a you know like a weed poking out of a crack and a sidewalk you know and you just have this overwhelming sense of the like wonder of the um of the world like the world is like just like the physical world is so wondrous and you you just get very immersed in the mome in the moment like the sensation of the moment sometimes that's the meaning of life i don't i don't think there's one meaning of life i think it's a population of instances just like uh just like any other category i don't think there's a better way to end it lisa the first time we spoke is um i think if not the then one of i think it's the first conversation i had that basically launched this pocket yeah that's actually the first conversation i've had to launch this podcast and now we get to finally do it uh the right way so it's a huge honor to talk to you that you spent time with me uh i can't wait for hopefully the many more books you'll write certainly can't wait to uh i already read this this book but i can't wait to listen to it because as you said offline that you're reading it and i think you have a great voice you have a great i don't know what's a nice way to put it but maybe npr voice in the best version of what that is so thanks again for talking today always my pleasure thank you so much for for having me back thank you for listening to this conversation with lisa feldman barrett and thank you to our sponsors athletic greens which is an all-in-one nutritional drink magic spoon which is a low-carb keto friendly cereal and cash app which is an app for sending money to your friends please check out these sponsors in the description to get a discount and to support this podcast if you enjoy this thing subscribe on youtube review it with five stars on apple podcast follow on spotify support on patreon or connect with me on twitter lex friedman and now let me leave you with some words from lisa feldman barrett it takes more than one human brain to create a human mind thank you for listening i hope to see you next time you