#413 ‒ The neuroscience of emotion： challenging conventional theories of emotion, how the brain predicts and constructs our experiences, and gaining greater control over how we feel ｜ Lisa Feldman Barrett, Ph.D.
00:00:00.000Hey, everyone. Welcome to the Drive podcast. I'm your host, Peter Atiyah. This podcast,
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00:00:53.200of a subscription. If you want to learn more about the benefits of our premium membership,
00:00:58.040head over to peteratiamd.com forward slash subscribe. My guest this week is Dr. Lisa
00:01:06.120Feldman Barrett, a psychologist and neuroscientist who has spent more than two decades studying
00:01:11.400emotion, the brain, and how our experiences are connected by the mind. Lisa is a university
00:01:18.060distinguished professor of psychology at Northeastern University with additional appointments
00:01:22.940at Mass General Hospital and Harvard Medical School, where she co-directs the interdisciplinary
00:01:27.980effective science laboratory. She's best known for her theory of constructed emotion, and she's
00:01:33.960the author of How Emotions Are Made and Seven and a Half Lessons About the Brain. I wanted to have
00:01:40.560Lisa on because her work challenges some of the most basic assumptions we make about emotions1.00
00:01:45.520and the brain. Namely, her work challenges the idea that emotions like fear, anger, and sadness
00:01:51.260are hardwired neurologic states, as well as the idea that the brain primarily reacts to the world
00:01:58.480around us. Instead, she argues that variation in emotional states both within and between people
00:02:05.700is the norm, and that the brain is fundamentally predictive in nature, and that the things we
00:02:11.980experience as emotions emerge from the brain's constant assessment and prediction of the body's
00:02:18.700future metabolic needs. In this episode, we talk specifically about how scientific averages can
00:02:24.420obscure meaningful differences between individuals and why emotions don't have universal biomarkers
00:02:31.140and why the variation in these emotions matters, why the brain is better understood as a predictive
00:02:38.700system rather than a reactive one, how memories and past experience fundamentally shape what we
00:02:44.540perceive, feel, and do in the present, why changing behavior can change emotion, and how deliberate
00:02:50.860practice can train and build new patterns of response, how the brain predicts and regulates
00:02:58.260the body's energy needs through allostasis and why that matters for stress, the relationship
00:03:03.620between chronic stress, uncertainty, social connectivity, and physical health, and how
00:03:08.640losing someone you love in a very literal sense is like losing a part of your body's
00:03:14.260regulatory system, and how this framework can give us more agency over our emotional
00:03:19.880lives without pretending we have complete control.
00:03:23.580So without further delay, please enjoy my conversation with Dr. Lisa Feldman Barrett.
00:03:33.620Lisa, it's so great to see you. And I know how busy you are. So I'm incredibly appreciative of
00:03:40.540you making the time to sit down with me today. I'm delighted to be here. So thank you for the
00:03:45.740invitation. So as we just discovered a few minutes ago, we both have this thing in common, having
00:03:51.640grown up in the same city. But it sounds like we've both lived in our current home longer than
00:03:57.540our previous home. Indeed. Indeed. I want to kind of understand when the first time you
00:04:07.120appreciated the idea of emotions as a, as a topic for study. Well, when I was in graduate school,
00:04:15.760I, so I, I went to graduate school to, I decided not to go to medical school and like all my other
00:04:21.080friends, and I decided to go to graduate school to be a clinical psychologist. And so obviously
00:04:26.880right away. You're starting to learn about emotion and how they work and what they are and so on.
00:04:33.660And so I thought I had a pretty good idea. And I was doing research for my PhD, actually on a topic
00:04:41.440that was something other than emotion, but I had to measure emotion. And I did it in a pretty
00:04:47.420standard way, which is to ask people how they feel. What I realized was that I wasn't able to
00:04:56.780replicate the experiment. So usually in graduate school, what you do is you take a published
00:05:01.480research study that's been published in a peer-reviewed journal. You try to replicate it
00:05:06.460just so that you can show that you know how to do an experiment. And then you go on and you do
00:05:10.800your own stuff. So I was preparing for my own line of work and I tried to replicate this experiment
00:05:15.760and I realized pretty early on into it that the findings were not replicating. So I'll spare you
00:05:23.600all the gruesome details, but over a three-year period, I tried to replicate eight different
00:05:28.920times. I tried to replicate experiments, probably a total of three or four experiments multiple times
00:05:34.480and wasn't able to do it. And my first response to that was, well, obviously I'm not cut out to be
00:05:42.040a scientist. Good thing I'll train to be a therapist. And then I took a closer look at my
00:05:50.580data. And I realized that while I was not replicating the published work, I was replicating
00:05:57.980myself over and over and over again, which to me was an indication that something interesting was
00:06:05.460happening. And luckily, I was working with research advisors who were willing to be persuaded by
00:06:13.200my observations. So I just can't resist pulling on this thread, though, in that I want to hear
00:06:20.340some of the details of this, because this was clearly such a pivotal moment in your career
00:06:24.820that it would be helpful, I think, for me and I think the listeners to understand the nature of
00:06:29.340these experiments, what was published and why you couldn't reproduce it, and perhaps more importantly,
00:06:34.860what it is that you kept reproducing that was distinct from the published findings.
00:06:38.720So usually when you ask people how they feel, you give them a set of adjectives or sometimes it's a set of statements, but some usually set of adjectives, which are labels for emotion categories, angry, sad, happy, whatever.
00:06:55.100And you ask people, you know, how frequently have you felt this in the last week or how intensely do you feel this now?
00:07:03.680And in particular, I was really interested in anxiety and depression.
00:07:08.140And so I was also using clinical scales.
00:07:11.040In this case, I was using a number of clinical scales, but including the back depression inventory and the back anxiety inventory,
00:07:18.760where you're asking you're giving people statements about symptoms like I feel sad I feel tired I have
00:07:27.320no appetite and you're asking people to rate the extent to which those symptoms describe their
00:07:34.340experience and in the the studies I was trying to replicate were basically this was a these were a
00:07:43.880set of experiments about the self, about your self-concept, where if you compare your beliefs
00:07:50.720about who you are right now in relation to, say, who you ideally would like to be or who you think
00:07:57.160you ought to be, maybe because your parents told you this or there's some, you know, standard that
00:08:02.380you think you have to meet, that if you fail, if you compare your experience of yourself as you are
00:08:08.820to who you ideally would like to be, you would feel depressed. And if you were failing to live
00:08:16.080up to the shoulds, the aughts, then you would feel anxious. This, of course, requires that people can
00:08:21.760distinguish between anxiety and depression as feeling states. I wasn't really dealing with
00:08:28.600clinical samples at this point. But one thing that I found was that I wasn't able to replicate
00:08:37.960this effect because when people reported feeling anxious, they also reported feeling sad or
00:08:44.060depressed. And when they reported feeling happy, they reported an absence of anxiety and they
00:08:50.080would report feeling calm. So they were basically reporting, I feel like shit or I feel okay,0.98
00:08:56.540even though the instruments I was using gave them the opportunity to be much more granular,0.95
00:09:02.080are much more specific. Now, here what I was doing was what most scientists do, which is to test a
00:09:10.580group of people and then look at the averages, right, of the group and make inferences about
00:09:16.500it, about, you know, what you think is true based on what you observe at the group level. And the
00:09:23.300way that I phrased the question at that time was very much dictated by what I had learned up till
00:09:30.220that point, which is that, you know, anger, sadness, fear, depression, anxiety, you name
00:09:37.420it, emotions are biological categories that are distinct and that people were having trouble
00:09:44.620identifying what emotion they were experiencing.
00:09:50.680And so my first way of phrasing the question was, well, I wonder what features of emotion
00:09:59.680they're ignoring that is causing them to fail to recognize the emotional state they're in.
00:10:07.520And very quickly, once I actually started, I did more than just dip my toe into the emotion
00:10:15.700literature and read other people's summaries. I actually started digging into the papers myself.
00:10:21.220I realized actually that the phrasing of that question was in error, which meant something
00:10:27.380really interesting was going on that an entire field seemed to be missing.
00:10:33.720So, Lisa, I want to just recap something there to make sure I'm understanding it correctly.
00:10:37.340What you just said actually answers a question I was about to ask, so I'll ask it only to
00:16:09.420actually research meta-analyses, you know, statistical summaries of many, many studies
00:16:15.020of thousands and thousands of people show that in Western cultures, people, adults in urban settings
00:16:21.680scowl about 35% of the time when they're angry. That's more than chance. So it gets you a
00:16:28.100publication in a good journal, right? But that means 65% of the time people are doing something
00:16:32.620else with their face. And half the time when people scowl, they're not angry. So if you used
00:16:38.840scowling as an objective measure of anger. Horrible predictive value. Yeah. And I might
00:16:44.160just add, that's a lot of what AI, uh, emotion AI is doing right now, but you know, that may be
00:16:49.780another topic, but you know, you'd miss, you'd, you'd miss 65% of the cases and half the time
00:16:56.320you'd over call it. Yeah. Yeah. Actually I would, I would say is, yeah, that's right. Yeah. You'd,
00:17:00.800you'd have both false positives and false negatives and every category works that way
00:17:05.100of emotion. And it doesn't matter what measure you're using. It doesn't matter, you know,
00:17:09.400does the amygdala show an increase in activity during fear? Yeah. More than chance? Yeah,
00:17:14.980about 30% of the time it does. But it often doesn't. And you see amygdala activation in
00:17:23.640many, many, many instances of emotion that are not fear and also across a slew of other phenomena.
00:17:30.620So the way that people deal with variants, right, what do you do when you're angry?
00:17:40.360Well, sometimes you scowl, but probably sometimes you frown and sometimes you might even smile or laugh.
00:17:46.840Sometimes you might remain silent, you know, and plot the demise of your enemy.
00:17:52.200You know, what does your blood pressure go up, go down, stay the same?
00:17:56.220yeah, it all depends on what you're about to do next, which depends on the situation that you're
00:18:01.040in. So emotions, when it comes to emotions, variation is the norm. People do a lot of
00:18:09.060different things in the same category. They feel anger can sometimes feel pleasant. It's not always
00:18:14.260unpleasant. Anger sometimes distances people from one another, but other times it brings people
00:18:20.300together. And then there are cultural, massive cultural differences that we haven't even,
00:18:25.920This is just like within one person over situations. Right. So I think part of what scientists do, the way to think about it, I would say, is that science, the world is complex. Reality is super complex. And scientists simplify in order to study things. And this is normal.
00:18:45.400And one of the things that they simplify is variance. They try to often control variance as opposed to measure it. So one thing you can do in an experiment is try to capture as much variance as possible and try to model that variance, try to figure out its structure and how to predict it.
00:19:08.860Another thing you can do is you can try to limit variability. And that's what experiments typically in emotion up to that point had tried to do. So they would limit the number of categories being studied. They would limit the number of instances being studied.
00:19:25.200So the sampling of people, the sampling of the stimuli, the triggers to provoke emotion would be limited.
00:19:35.960The modeling, the specifications of the statistical modeling would be designed in such a way as to remove variants or to get rid of variants as error variants.
00:19:47.520And when you start to look a little more closely at the evidence, you can uncover that variance.
00:19:54.700And you can even design studies to cultivate that variance, actually, to try to observe it.
00:20:01.420And in the end, that's, you know, that's what I turn to were methods like that.
00:20:08.360So, Lisa, I'm hearing two things that are related in question, but they seem distinct to me.
00:20:13.520And I want to make sure that I'm understanding this because it seems to be the foundation of what was the widely held view at the time you were doing these experiments.
00:20:21.920The two things are, we should be able to objectively measure an emotion. And again, I think that's a very straightforward proposition based on people's understandings of what's subjective versus what's subjective. We should be able to know your emotion without you telling us. Is that a fair way to say that?
00:20:40.640Yeah, what I would, yes, it is. But I just want to point out that always objectivity is within relation to the subject, meaning you should be able to measure something in a subject that the subject doesn't tell you.
00:20:53.520But I think it's important to also realize that measurements are never objective because scientists, a scientist, there's the synonym for a scientist's observation is the scientist's experience.
00:21:11.600I mean, sure, you know, you can quantify numbers.
00:21:14.680Well, that's why we have to, that's why we do blinding.
00:21:16.820That's why we want double-blinded studies whenever appropriate.
00:21:21.340You can have double-blinded studies, but if you think that a double-blinded study actually removes your theoretical view from your study, you're deluding yourself because all experiments are theory-laden.
00:21:33.980They're theory-laden in the way they're designed.
00:21:53.860It's a mistake that scientists often make.
00:21:56.940Once you realize that you yourself have a point of view, and even though you try really hard, you can double-blind things, you can, you know, there are a lot of things you can do to try to control the influence of your own point of view.
00:22:24.340So let's take something, let's take the following experiment.
00:22:27.320I have a hypothesis that I give you, if I give you this pill, it will lower your cholesterol.
00:22:31.600So I'm going to take 100 people and without knowing which ones are which, half of them are going to get the pill that I think will lower their cholesterol.
00:26:10.820And so these scientists, they were immunologists, they were psychologists, they were physiologists,
00:26:15.720that they did is they took samples of people and each person, they stuck them in a hotel
00:26:20.560room. And then they quantified everything about that, how much they slept, what they ate, you know,
00:26:26.540basically how much, you know, mucus they blew out of their nose. Like really they were quantifying
00:26:30.840everything. And then they took the same amount of virus, viral load was identical, and they just
00:26:37.900placed it in each person's nose. And then they watched what happened. And they observed that
00:26:44.940depending on the experiment, there were about five, I think, five of these experiments done
00:26:49.580or something like that, between 20 and 40 percent of people showed symptoms of respiratory
00:26:55.440illness. That means the majority of people did not get sick from being exposed to a virus.
00:27:02.940That means a virus is a necessary cause of a respiratory illness, but it is not a sufficient
00:27:09.240cause. But that's most of biology, right?
00:27:15.120Yes, it is. But if you stand up in a medical school or at Grand Rounds and you say to a bunch of physicians, as I have, do you think a virus is the cause of respiratory illness? Like 90% of people will put their hands up. Why does that matter? And it's not physicians only. I mean, it's like people. It doesn't really even matter.
00:27:38.100unless you are somebody who studies complexity theory, you probably think in terms of these
00:27:44.180simple causes. But in fact, you can't develop the symptoms without the virus, okay? But the
00:27:50.880virus is, if you're controlling viral load, the virus is not a sufficient cause. There are other
00:27:57.040factors that are causal. And those factors are also necessary, but they're also not sufficient.
00:28:05.340Yes, for sure. So there's two things there. Maybe the virus example is a bit tough because there's immunity, but maybe they normalized for previous immunity or previous exposure in the 60% that didn't get it. But I still think this line of inquiry around causality is relevant. Because if you can establish that the virus is necessary but not sufficient, and that it plays a causal role, then the removal of the virus removes the condition. Correct?
00:28:29.880For sure. But here's what I would say. In a large clinical trial, you do a large clinical trial and you find that, let's say, I'm going to make up some numbers, but let's say 30% of people show improvement on a placebo.
00:28:47.400And so that means that you need some other much larger number in your treatment group to show an effect.
00:28:55.060And let's say you only find, like, 40% of the people that the drug worked for 40% of people, and it's not statistically different from the placebo, your conclusion would be that the drug is ineffective.
00:29:18.440And it's not effective for other people because there's complex causation and there are multiple factors. So I do think that there is a problem when you're reasoning about the outcomes of individual people based on group or averages. Yes. And this is, you asked me, you know, how do people manage, how do scientists manage variants? One way we manage variants is we ignore it.
00:29:45.120Yeah, we collapse it. Yeah. And instead, we should be modeling it. And you give me any example of, you know, I mean, I think there are lots and lots and lots of examples where, you know, I have my own personal examples that I've talked about on other podcasts, you know, where, you know, which I could go in, you know, but where it matters.
00:30:08.560Yeah, feel free to share one. I mean, this is a fascinating discussion.
00:30:11.700Yeah, so, I mean, you know, a number of years ago, I was diagnosed, as many people are, with Hashimoto's disease.
00:30:19.180And I went to see an endocrinologist. So that's like, you know, where your immune system is destroying your thyroid.
00:30:23.960And I went to an endocrinologist who was a great endocrinologist who's super, super knowledgeable.
00:30:28.660And he said, I said, so what's the treatment? And he said, well, we just wait for your immune system to destroy your thyroid.
00:30:35.160I mean, he wasn't being flippant about it, but he said, well, wait till your thyroid is destroyed and then you start taking synthetic hormones. And I thought, yeah, no, I don't think so. And so I did something that I often do when I'm dealing with my own physicians.
00:30:49.280I went to PubMed and I just started to read about thyroid diseases.
00:30:53.940And admittedly, I'm not an expert, but, you know, I have some ability to read papers.
00:30:59.540And I found a series of studies which showed really clearly that if you give low doses of levothyroxine, which is a synthetic thyroid, you can arrest the progress.
00:31:35.380And he was game because, you know, I mean, it's not terribly dangerous to take a low.
00:31:42.040I mean, there are some things you have to work out, watch out for.
00:31:44.180But we did it together because, you know, he was very, we were, we had an open dialogue. And sure enough, not only did it arrest the disease, it actually reversed some of the damage.
00:31:59.320Now, and sorry, just to make sure, does that mean that your antibodies went from positive to negative?
00:32:05.020it means no it means that like nodules disappeared from my thyroid and you know so what it means is
00:32:13.980that the damage was that the the antibodies went down the damage was actually first arrested and
00:32:22.160then eventually started to reduce a little bit and now you know i'm kind of like a borderline case
00:32:28.640i was not a borderline case to begin with it should have progressed but it didn't
00:32:32.740And I'm not saying it's magic. What I'm saying is that this is not something that everybody who has thyroid disease should do. It's not going to work for everybody. Studies already show that. But it will work for some people and it worked for me.
00:32:46.080And this is one example in many, many cases where when you set aside the averages, what the averages tell you, and you look for variation and you look for meaning.
00:32:59.660I mean, it could have happened that it did nothing, but that's not what happened in this case.
00:33:04.320That doesn't necessarily mean that, like I said, that this will work for everybody and it won't.
00:33:09.580And it might not work for me forever either.
00:33:12.120But the thing is, so now I'm on a low dose of levothyroxine and I'll be on that low dose
00:34:14.880Let alone replicate. Let alone replicate.
00:34:16.680No, no. I mean, I agree with everything you're saying, Lisa. I probably, on a personal level,
00:34:22.460frame it a little bit differently. And I'll frame it back to you. But I completely agree.
00:34:28.100I have sort of a way that I talk about this in the context of my world, right? So I talk about
00:34:32.840this thing called Medicine 3.0, and I contrast it with Medicine 2.0. And I say one of the
00:34:38.240limitations of Medicine 2.0 is it homogenizes data, which is just basically saying what you're
00:34:43.540saying, right? The bedrock of Medicine 2.0 is the randomized control trial, where we take a very
00:34:49.740heterogeneous group of individuals, we apply a clean, homogeneous treatment, and then we homogenize
00:34:56.220what comes out and that becomes the recommendation. And on average, that is an excellent way to
00:35:01.800practice medicine. Well, I would say on average, it's a better way to practice medicine than the
00:35:07.420other ways for sure. Yes, yes. And then where I think we would agree is the challenge with that
00:35:13.680is the variability gets lost. There's nuance that gets lost. So I'll give you one example
00:35:18.720from my world. There's a drug called Zetia or ezetimibe. It is a cholesterol-lowering drug
00:35:24.780And it has a very specific mechanism of action. It works by blocking one of the transporters on the cells of the gut and the liver that reabsorb cholesterol. Now, when you look at the clinical trials of Zetia, given as monotherapy, it is rather underwhelming.
00:35:44.920and we could, without getting into the nuances of it, there was a huge debate as to whether
00:35:50.500anyone should ever receive Zetia and monotherapy. And it was viewed as not an evidence-based approach
00:35:55.880because it didn't have the hard outcome trial that said, if you give Zetia and monotherapy,
00:36:00.120you will save lives. But once you understand the mechanism of how ezetimibe works and you
00:36:05.880understand that we can measure a person's cholesterol absorption using other biomarkers,
00:36:11.660We could selectively target people who are very high cholesterol absorbers, and those are the people that would do very well in monotherapy. And lo and behold, we do this now. This is what I would call precision medicine or evidence-informed medicine, right? And I think there's still a lot of pushback to that approach.
00:36:29.500And I would argue that what you've pointed out is another example of that, which is to say, on average, giving Zetia as monotherapy probably doesn't save lives. But if you could target the people who are super responders.
00:36:42.000Yeah, for sure. For sure. For sure. So let me just be really clear. I'm not saying we should throw out clinical trials.
00:36:47.580No, no. And I want to make sure that the listeners hearing, you and I are on the same page. I think what you're saying is very important. And to me, this is exactly where AI could make an improvement in how we interpret clinical trials. Because we wouldn't have to hide, we wouldn't have to try to compress variability. We could actually explore it more fully.
00:37:09.660Well, I think, so you're talking, you know, there are two things that you're talking about now. You're talking about how science should be conducted and then what AI can do or not do. And those to me are somewhat separate because it all matters how you, it matters a lot how you use AI.
00:37:27.480Well, let's put a pin in the AI. Let's come back to it because I want to talk about it in the context of your work as well.
00:37:32.440Yeah. But what I will say is this, that in the science of emotion, there are no biomarkers.
00:37:44.920But I would also say that, and maybe this is what, you know, medicine 3.0 is. I don't know. But, you know, but I would say there are a lot of very brilliant people who, if they put their minds to it, could figure out other ways to do science.
00:38:02.440that didn't require using group averages.
00:38:07.240So what you describe here with this example
00:39:00.180How many countries participated to discover the Higgs boson? It's because they thought it was important. Do you think, I mean, I would love to see what a bunch of, what medical science could do with that kind of cooperation and that kind of money focused on one problem.
00:39:19.300I mean, they built this. I mean, I'm not saying it's good what they did. It's just that that kind of ingenuity and cooperation and financing is not available. Maybe it's available in some circles in medicine. It's certainly not available in behavioral science or in neuroscience, frankly.
00:39:39.900And so they did something very clever. I think there are other clever things that we could do now. There is the technology that's available now to start doing experiments differently. You just have to have the ideas, the will, and the money to do it.
00:39:59.260okay i want to go back to one other thing that you said at the outset that i i think is important
00:40:06.580for us to ground ourselves in which is part of what maybe we would call this foundational belief
00:40:11.160you came into so one of them we've just talked about which is the objective measurement of
00:40:15.480emotion but then there's something else you talked about which is a belief that emotions are
00:40:21.020universal, that emotions are hardwired into our nervous system. And it sounds like you were saying,
00:40:30.620no, I don't think that's the case. These two observations, that emotions are not hardwired
00:40:36.940into our nervous system, and that we don't have an objective way to measure them with a biomarker,
00:40:43.660those don't require each other to be correct. Those are independent observations, right?
00:40:47.660No, exactly. And also, I mean, I think it took me, oh, geez, probably a good 20 years before I was willing to say that there was no biomarker.
00:41:04.140I mean, you know, because I had to learn a bunch of literature.
00:41:11.600I had to retrain basically three times in order to be able to make that claim.
00:41:17.440You know, I think one of the things that I became very clear in my own mind about was that I wasn't going to be able to rely on the summaries of other scientists.
00:41:28.940I wanted to be able to collect the data and observe myself, and I also wanted to be able
00:41:37.100to dig into their studies and understand for myself. So basically, I was taking a very empirical
00:41:44.140stance towards published studies. When graduate students sometimes ask me, well, what do you do
00:41:51.280when you read a paper? I say, well, I read the few sentences in the introduction that outline
00:41:57.800the hypothesis. I read the methods and the results and I throw the rest away. I don't read the
00:42:02.240introduction. I don't read the discussion. I don't care. I want to make my own judgment about what I
00:42:08.700think that shows. And then I will go back and, you know, maybe read or maybe ask colleagues who I,
00:42:18.080you know, trust. Because I'm very aware of how theory-laden publications can be. And so it's
00:42:28.200not something, it's not like I ran a couple of studies in graduate school and came to this
00:42:31.860conclusion. I ran some studies in graduate school and discovered I had to learn how to measure facial
00:42:37.780movements objectively. And then when that didn't pan out, I had to learn physiology so I could
00:42:45.340measure physiological patterns to see if there were objective biomarkers. And then when that
00:42:50.700didn't pan out, I had to retrain in neuroscience to be able to do brain imaging to check that.
00:42:58.060Right. I mean, so I'm not, these are not conclusions. Same thing about universality.
00:43:03.760We didn't, I didn't just read a bunch of papers and test a bunch of college students. Our lab
00:43:07.780went to Namibia and we tested the Himba, you know, who live in Northwestern Namibia.1.00
00:43:14.360We went to Tanzania and tested the Hadza hunter-gatherers. We went to rural China. So, of course, we used other people's experiments, too. We used their data. We used their studies to draw conclusions. But we didn't only do that. We also went and did our own studies where we used multiple methods.0.99
00:43:34.900And it's very, very clear what you find.
00:43:38.440The findings are really, really clear, and they're clear across domains.
00:43:53.060It's not that we can't say anything important about emotion.
00:43:56.220And also, I didn't come up with my own views on what emotions were or how they work right away.
00:44:03.340I really spent really many years trying just to figure out the simple answer to the question of, are there biomarkers and is there universality?
00:44:15.940Like, and what is it that, you know, infants actually can do or can't do?
00:44:21.520And then I started to think about, well, we have a real paradox here, right?
00:44:28.300I experience emotion and I'm pretty certain about what I experience and I'm sure you do too. And
00:44:34.300you and I could be, you know, at a coffee shop having a conversation and I would feel like I
00:44:40.580was reading your emotions and you would feel the same. So how is it that this is the case and then
00:44:46.300there are no biomarkers? Like this just felt like a really big puzzle. If it makes you feel any
00:44:51.640better, Lisa. In the world where I spend all of my time, we don't have a biomarker for aging.
00:45:00.620Now think about that for a moment. Is there anyone listening to us that disputes that we age?
00:45:05.860No, of course not. We are aging. Do we all have a gestalt of how somebody is aging? Sure. I can
00:45:12.360look at a person who tells me that they're 60 and I say, gosh, they don't look a day over 45.
00:45:16.720Okay. They're probably aging slower, at least in some dimensions. Of course, I can't see what
00:45:21.620happening inside their body. And yes, on average, we can measure things that are changing as a
00:45:27.840person ages, their bone density goes down, their muscle mass goes down, they become a little bit
00:45:31.620more insulin resistant, et cetera. But to actually suggest that at the individual level, I could
00:45:37.340measure anything in you, Lisa, and then do an intervention and then measure it again in a year
00:45:43.360and definitively conclude I have slowed your rate of aging. Absolutely not. Now, there are a lot of
00:45:49.640people that tell you they can do that it is sure absolute nonsense i mean this is challenge i mean
00:45:55.980this is brutal it's a it's a brutal reality i don't i don't think it's a brutal reality i think
00:46:02.100it's a reality and i think that that reductionist science isn't the method to get at that brutal
00:46:10.280reality so so does that mean you've given up on the biomarker do you believe that in 10 years we
00:46:16.140will have biomarkers for emotions no i don't think it works like that okay what i will say is
00:46:24.040if i measure you personally peter many many many times over many many many situations and i used a
00:46:33.280personalized ai for you i could probably learn to reasonably predict the vocabulary of angers and
00:46:45.760sadnesses and fears and so on that you experience that's what i think is plausible um so but that
00:46:55.780but that won't you you can't use that in a in an experiment you do with a hundred college students
00:47:00.280right that wouldn't help you well you well you what you would have to do is my guess is that
00:47:06.880that there would be some you could assess the degree of similarity between people
00:47:13.980So you and I grew up in Toronto, probably approximately around the same time.
00:47:20.280And that means we're similar, at least on that dimension.
00:47:24.180We both grew up around horrible Toronto Maple Leafs.
00:47:27.260Harold Ballard owned the Leafs, like literally the worst team in the league.
00:47:42.080with our differences, obviously, you know, you're a man, I'm a woman, you know, so, but the point is
00:47:48.020that there are some features on which we're similar, and there are some features on which
00:47:51.460we're different. And it's an empirical question as to which features matter, to be able to use,
00:47:58.040to be able to generalize, to find, you know, well, you know, you can look for similarities
00:48:04.340in the algorithms that predict individual people and potentially inductively discover
00:48:12.860how, whether that similarity exists and how to capture it and model it. So what I'm saying is
00:48:19.940that it's possible that there could be more generalized algorithms, but you would not start
00:48:26.300with the simplification. You don't start with the simplification of getting rid of individual
00:48:32.740variability. You start by modeling individual variability, and then you look for places where
00:48:37.800you can reduce it on the basis of empirical evidence. That is a justified way, I think.
00:48:45.020It's just a much more cumbersome and expensive way to do the research. And it has huge implications
00:48:53.400for the incentive structure and science would have to change. And a lot of things would have
00:48:59.840to change if we did research that way on a large scale. But it all comes down to what people care
00:49:06.660about and what they want to invest their research dollars in. And, you know, that's not for me to
00:49:12.840say. That's above my pay grade. So what can we say about an emotion? If you were now trying to
00:49:22.280explain to somebody what emotions are, we've said two things that we know on the negative. We know
00:49:29.780that they can't be measured objectively. And we know that they are not necessarily hardwired into
00:49:35.860each of us as identical states. Fear is not universal. Let me ask this question, Peter,
00:49:41.660what is hardwired into the brain? What is hardwired? Yeah, it's a great, I mean, I think
00:49:46.400certain reflexes are clearly hardwired, right? So for example, if I shine a bright light into your
00:49:53.080eye, I think it is hardwired that your pupil will constrict, right? It will, but how much will it
00:49:59.320constrict and you know even reflexes which are hardwired are are not hard they don't always look
00:50:05.180the degree to which sure yeah yeah no well but that matters i think so what i would say is that
00:50:11.160there is very little in it's just like genetics right i mean they're sure there are some cases
00:50:18.080where a single gene predicts a single characteristic you know with a single allele
00:50:24.060Right. I mean, but those are really rare. Most of genetics doesn't work like that. And I'm certainly not the first person to point out that, you know, NIH spent a tremendous amount of money trying to map the human genome on the assumption that that, you know, would actually, if we just knew the genes, we'd be set.
00:50:51.360a lot of the devil is in the details of how, of the mechanisms, right? Because of this complex
00:50:57.920causation that happens. And I would say the same is true in the case of emotion and pretty much
00:51:03.620the case of anything a brain does. So first of all, I would not, when someone asks me,
00:51:08.760how do you define emotion? I say, I don't. You can't. How do I define, I could, the way I would
00:51:15.820define it would be generic. It would be like, well, any mental event basically could, you know,
00:51:22.660your brain's most important job is regulating your body, coordinating and regulating your body
00:51:28.020in the most efficient way. That's why brains evolved. They evolved for, they evolved at the
00:51:34.960same time as invertebrates. I'm only speaking about vertebrates. I don't know anything about
00:51:39.180invertebrates, but invertebrates, they evolve around the same time as you get visceral organs
00:51:43.720and, you know, a head and distant senses and eyes and ears and so on.
00:53:35.560It means the brain has to infer what caused that loud bang, what caused that flash of light, what caused that tug, what caused that change in glucose.
00:54:23.920Well, what I would say is that why is it?
00:54:28.120because I think that there are a lot of questions that you could answer about emotion without having
00:54:33.200to take on the big question of consciousness. But I would say the following, I guess, that
00:54:40.200I don't know if it's that we're asking the wrong questions or asking questions in the wrong way,
00:54:46.600but a lot of people have a lot to say about the nature of consciousness, none of which
00:54:52.600actually explains how it is that we are sentient and how it is that we have content, that there's
00:55:02.920content, that we get content out of electrical and chemical changes. And I just prefer not to
00:55:11.860speculate. It doesn't mean that I'm not interested. It doesn't mean that I'm not curious. I'm very
00:55:18.880interested and curious, but I also, I'm not a fan of talking out of my ass, you know, like I just,0.98
00:55:26.740I think that we don't know enough maybe yet to ask the right questions or whatever. So we should0.97
00:55:35.180continue to explore and debate and whatever, but you know, like people publish books and they make
00:55:42.620claims about consciousness. So here's what I have to say. Are there aspects of emotion that you're
00:55:49.040not conscious of? For sure. That has to be the case. You're not conscious of most of what goes
00:55:55.600on inside your own body, thank God. Because if you were, you'd never pay attention to anything
00:56:01.140outside ever again. Just think about the last time you ever had, like, gastric distress. I mean,
00:56:06.260you just can't, you know, you can't focus. There's so much going on in there, right? And
00:56:12.140we don't have access to most of it. Most of the details are compressed out of the signals
00:56:17.280before they reach the brain. What the brain is receiving about metabolic and interoceptive
00:56:25.560signals from the body is more like a gist. It's not getting specific details about everything.
00:56:32.700It might compute details, like it might infer those details, but like there's no visceral,
00:56:38.100there's no visceral map of the body in the brain that anybody has found some people claim they
00:56:44.440find it but when you look closely they don't it's not like a retina topic map right so your
00:56:51.620your brain has v1 primary visual cortex has a map of the retina there's array to array mapping
00:57:00.080meaning you have an array of cells in your retina you have an array in your brain they map
00:57:05.360the mapping changes all the time right so uh what a like we would say the receptive field of a v1
00:57:14.240neuron a neuron in primary visual cortex changes actually with the context of with the neural
00:57:19.940context of the brain but it's always the it's always a map right but there is no map of the
00:57:26.520body like that in your brain just like there is no map of your olfactory cyst there's you know
00:57:31.840you have olfactory receptors in your nose, there's no map. It's no spatial map in your brain. That
00:57:38.360information is compressed out of the signal before it ever reaches your brain. There's temporal
00:57:43.800information, but not, not spatial information. In the body, the brain has, like, it can tell,
00:57:51.100there's some spatial information, like, is, is a signal coming from the thorax, upper thorax? Is it
00:57:56.260coming from the gut. It's not even gut so much as lower part of your abdomen, upper part. There's
00:58:03.000a little bit more detail here. But it's nothing like a retina or a cochlea where you have array
00:58:08.380to array mapping. This turns out to be super important. In science, people talk about
00:58:12.960exteroceptive versus interoceptive, like signals that come from the world versus signals that come
00:58:18.840from the body. That turns out not to be so important, I think. I think what's more important
00:58:23.020is is it a proximal sense or a distance sense meaning the the distance senses the best examples
00:58:31.760are vision and audition they're processed the the signal processing the compression of those signals
00:58:38.020is very different in the brain than say olfaction which is a proximal sense or gustatory or anything
00:58:44.740interoceptive gustatory is usually considered um interoceptive taste is not but gustatory you know
00:58:51.780signals from the gut are interoceptive. So, and then there are a bunch of signals that kind of
00:58:56.680don't fit the exteroceptive, the internal-external distinction, like proprioception. Is that internal
00:59:03.000or external? It's kind of both, right? So if you just look at the signal processing, the signal
00:59:08.700processing properties, then other distinctions become important. And I would say it's the same
00:59:15.540thing about cognition and emotion or thinking and feeling there are a lot of distinctions
00:59:21.880that you can find in the brain or anywhere else to distinguish what is a thought and what is a
00:59:28.500feeling but there if but if you look at the signal processing you know architecture and dynamics
00:59:39.760Other distinctions become important for explaining how a thought arises or how a feeling arises.
00:59:48.340None of those explain how you get from, you know, a very, very high dimensional set of chemical and electrical signals to a very low dimensional mental feature like pleasantness or unpleasantness.
01:00:07.300And if they're claiming to, which some people claim they do, then they're lying either to you or to themselves, probably to themselves in your presence.
01:00:19.340So let's try to disentangle without defining an emotion some of the broad differences between, say, the positive and negatively valenced emotions.
01:00:32.780So again, we'll go back to this idea that there's a belief that, God, some of these are really primal.
01:00:37.560Like I'm going to anthropomorphize this as well, right?
01:00:51.320What is it that you could say today we know about that emotion?
01:00:55.980i'm just gonna let the point go about we couldn't have evolved without fear it's a primal emotion
01:01:04.460and by the way feel free to attack that point but by the way i don't think i want to attack that
01:01:07.980point it's just i don't think that's going to take us down a productive avenue but here's what i'll
01:01:12.280say about fear there are no pleasant or unpleasant emotions you think fear isn't pleasant people pay
01:01:17.480money to go on a roller coaster they pay money to go to a horror movie i used to run a haunted0.65
01:01:22.440house in my basement for charity for 13 years, an auspicious number, where we scared the shit
01:01:29.620out of people. We donated all the money, but we scared, we basically, I used to tell people,
01:01:36.540I scare little children for, you know, I have their parents pay me and I scare little children
01:01:42.800for money. And then I donated all to the Boston Food Bank, which is what we did for years and
01:01:47.080years and years. And we had three levels of scary, you know, so people could choose. And
01:01:52.080all of my graduate students... But is that a uniquely human feature? Is there any evidence
01:01:57.480that anything else in the animal kingdom will voluntarily put themselves in a situation that
01:02:03.060produces fear? Yeah, absolutely. I mean, there's a whole literature on how animals play.
01:02:11.520And they're often playing in ways that would, you know, that could be considered practice. Like it's a way of foraging for information and for like innovation, basically. Whether they are feeling fear, I can't comment on that.
01:02:30.500But what I would say is that you don't have access to whether an animal, what an animal feels. If you look at an animal and you say that animal is fearful, that's your experience of what those signals mean out of that animal. And that doesn't necessarily mean that it tells you anything about what's actually going on inside that animal from a feeling perspective.
01:02:49.440However, I think you can say, like, if you watch an animal work hard to avoid certain stimuli that will cause it damage, right? Or if an animal is willing to, like, expose its—so there are these studies, you know, where they'll, like, damage an animal in some way, and then the animal will actually work hard and even expose itself to the possibility of a predator in order to get it.
01:03:19.440an opioid. That's a pretty good indication, I think, that the animal is feeling something
01:03:25.740like pain. Maybe not the way we feel pain, but it's definitely feeling something unpleasant
01:03:30.980because it's willing to incur a cost, a significant cost, in order to get a drug that will
01:03:38.340reduce, presumably, its awareness of the, maybe awareness of the, but, you know, its feeling
01:03:47.600in relation to some kind of tissue damage that's very different than what like a fly will do
01:03:53.240you know where it does you know you damage the leg of a fly or a wing of a fly and it will still
01:03:59.260continue to behave in exactly the same way then you know you can sort of make inferences that way
01:04:05.140which i i so i'm not talking about pleasure and pain i'm talking about the specific
01:04:08.880the specific categories and distinctions that we make about humans that come from human experience
01:04:15.800you have to be super careful when you impose those on other creatures to which for which we have no
01:04:23.880access to what they experience and not so i'm not advocating to assume that they experience nothing
01:04:29.540i'm saying that you just have to be careful and there are lots of reasons for being careful both
01:04:35.040for them and for us but what i would say about fear is that you know what would you think is
01:04:40.000the prototypic response in fear to freeze or to run away well you know i think it varies and by
01:04:49.340the way well sure it does but i mean the theory is in the literature if you ask most people fight or
01:04:54.980flight you know they're like flight flight they'll freeze an animal will freeze you will freeze or
01:05:00.880you will flee but there's a you know a culture where what people do when they feel afraid is
01:05:09.340they go to sleep that seems weird to us but you can look in the animal kingdom and you can find
01:05:16.300out that in invertebrates in the water animals when there is a predator will play dead they will
01:05:27.460slow their heart rate so sharks can't find them they will not move they're not freezing
01:05:36.320they're reducing their detectable output so that the predator can't find them so I I think I guess
01:05:48.480what I would say is when it comes to fear what we could say is that variation is the norm
01:05:52.780and that that what you feel in fear what you do in fear depends on the situation that you're in
01:10:33.540There's just it's not one or the other.
01:10:35.460They're both, you know, it's like blue and green together make turquoise.
01:10:41.200You wouldn't say it's blue or it's green.
01:10:43.720you would say it's turquoise it's both they're not distinct states similarly there are cultures
01:10:50.640where there are somatic descriptions for emotion like that is the nature of emotion in those
01:10:59.120cultures so we need to have a theory of how a brain and a body together in a world full of
01:11:12.360other brains and bodies, create a mind. And that has to work for everybody on earth. It's not just
01:11:22.060to explain Western categories. And that may mean that emotions and thoughts and perceptions are
01:11:30.560things we have to explain, but they are not themselves explanatory categories. They're not
01:11:35.980categories that explain anything. So are you saying then that the universal theory that is
01:11:46.600culturally agnostic is that the goal of the brain is to, well, there's two things I've heard. One is
01:11:54.140a main priority of the brain is to support the body physiologically, metabolically, et cetera.
01:12:01.620And two, the brain is a predicting machine and emotions are arising out of predictions of physical sensations or the consequences thereof. Is that directionally what you're saying?
01:12:14.620Yeah. I mean, I would never claim that it's culturally neutral because I, you know, can't claim that. I'm, I live in a, I was pickled in a culture just like you and there are other, but you know, I think, I think that it's a reasonable, it's a reasonable hypothesis.
01:12:32.120But if it's biological, it should, I mean, it doesn't matter what culture you live in. There are certain biological things that are true across the board.
01:12:40.300I'm just being, I'm being a little humble here, Peter.
01:12:44.780Biology in Western science, I'm not immune to, I don't think, I'm just being, I don't think it's relevant to say, I wouldn't claim, I'm trying to think of how to say this without being too negative.
01:13:01.220um i'm very aware of the fact that some of the beliefs that i hold as a scientist um come from
01:13:11.620the fact that i was raised in a western culture and i use western concepts and methods of science
01:13:17.600and not everybody you know adheres to that but i would say that i can defend that statement by
01:13:25.360looking at anatomy, by looking at physiology, by looking at brain evolution, evolutionary biology.
01:13:32.780I can defend it by looking at developmental neurobiology. I can defend it by looking at
01:13:39.200signal processing and engineering. I think that when multiple fields come to the same conclusion
01:13:46.920using completely different sources of evidence and they don't talk to each other all that much,
01:13:53.060then you know that you're probably onto something. The idea that the brain predicts and doesn't react
01:14:00.440is actually a concept that is in other cultures. And it's been in our culture for many, many,
01:14:07.080many years, like centuries. But this is very counterintuitive. So I really want to spend
01:14:12.600some time on this because I've always felt that my brain is just a reaction machine, right? Like
01:14:17.980I'm riding a bull and that sometimes that bull is just walking along and everything is fine.
01:14:24.960And sometimes it's bucking like crazy and my vertebrae are getting crunched. So let's maybe
01:14:32.320in any way you like, let's go through the different lines of evidence as you've laid
01:14:37.120them out from different sort of empirical disciplines to how we can say that the brain
01:14:42.360is not reacting. Sure, sure. I mean, just before I do though, I just want to say two things. One
01:14:47.560is, so for you, it's a bull. And for John Height, I think it was an elephant. And for Plato, it was
01:14:53.240two horses and a charioteer. You know, like that idea that we have an inner beast that we have to
01:14:59.540tame and kind of control is wrong. It feels that way. It feels that way to me. But it's not
01:15:08.060defensible. It's not a great metaphor because it doesn't really reflect, doesn't really reflect
01:15:13.700the evolution and anatomy of the brain, for one thing. So that's called the triune brain. And
01:15:19.620it's just, you know, it's really, really popular. But the evidence against that has been in
01:15:24.140molecular genetics for at least 50 years, if not more. So that's just, we just have to take that
01:15:30.540off the table. I just finished doing a video, actually, with a videographer, just kind of do
01:15:35.520like a, to explain why this is not the case and show for the first time, you know, a depiction
01:15:42.640of how a common kind of manufacturing plan for a vertebrate brain
01:15:49.000could produce all different kinds of brains in vertebrates.
01:15:52.300Really, it's just mammals, but you could make inferences to vertebrates, I think, in general.
01:25:36.960And then you, a week later, take the blindfold off.
01:25:41.320V1 goes back to mostly processing visual signals.
01:25:44.700So what I'm saying is that, first of all, that what we think of as, you know, brain regions that have very, very, very specific meanings from a psychological standpoint probably don't.
01:26:01.620They certainly have specific signal processing capacities based on their architecture and what they're connected to and so on.
01:26:08.300But a lot of the distinctions that we make, like I met a woman once who had no somatosensory system at all.
01:26:17.480Like it was just congenitally not there.
01:26:20.980But she was able to eat only by looking at herself in a mirror while she ate.
01:26:28.280So she was using visual signals to control her motor movements.
01:26:34.600Meaning if she tried to eat without a mirror, she wouldn't know how to move the spoon.
01:26:39.580No, she wouldn't. Yeah, she wouldn't know how to swallow.
01:26:45.760So sensory signals are not so that we know the world.
01:26:51.080Sensory signals are in the service of controlling motor.
01:26:54.420They're in the service of motor control.
01:26:56.620They also let us know the world, which is relevant for motor control.
01:27:00.220So I'm saying that, you know, when you start to look at the architecture of the brain, and we've only talked about architecture, we haven't talked about any of the other types of evidence yet, you start to see things differently. You start to realize, oh, well, actually, so most of the synapses are predictive synapses. And that's interesting. And that motor signals, copies of those signals are going everywhere. And they're beginning to construct experience before the sensory, other sensory signals arise.
01:27:28.580like if this were a different format i could show you an image an illusion that you would
01:27:37.160experience as red you would literally experience red and there would be no wavelengths of light
01:27:44.760in that in that range that were hitting your retina but you would experience red so you would
01:27:51.300be like predicting red remembering red how your experience of red what do you mean how how would
01:27:58.200you make that happen what would you do you're saying i mean you could do that obviously by
01:28:03.240stimulating my brain in the right areas no i don't have to stimulate your brain with electrodes i
01:28:07.440could just stimulate it another way so what you do is you you show people well i'm gonna ruin it
01:28:13.120now for everyone who hasn't seen it but you show people um a stop light like a like a traffic light
01:28:20.940red orange green except the red one where red is supposed to be is gray
01:28:26.760there's no there are no wavelengths of light there are no long wavelengths of light coming
01:28:33.020from that spot but because you've had countless numbers of statistical like there's been a
01:28:41.580countless numbers of statistical regularity for you you know facing this array of signals
01:28:47.800your brain predicts that that's red and you see red you see red until i move in two gray
01:28:58.220boxes and sit them right beside and then all of a sudden the light looks gray
01:29:04.520and then i pull the boxes away and now it goes back to being red this is something i've never
01:29:11.460had i've had anyone not experience this probably but they haven't told me i mean it's one of the
01:29:16.120I have an illusion where I have that I got from somebody who made that where it's electrical towers are playing jump rope.
01:29:23.900So these like electrical towers are playing jump rope.
01:29:26.360It's just a video, but you can hear the towers hit the ground.
01:29:32.780You feel the vibrations in your chest.
01:32:52.460So every experience you have, every action you take,
01:32:56.660is a combination of your remembered past and your sensory present.
01:33:01.860The sensory present is there to confirm the remembered past or to change it.
01:33:07.240And we have a special word in science for changing the remembered past.
01:33:13.940We call it learning. That's what learning is.
01:33:20.620What accounts for the differences between individuals? Why are some people better at
01:33:26.300prediction? So let's use baseball as an example because it's a very concrete example. So what
01:33:32.560makes Shohei Otani or Aaron Judge better at hitting home runs? Like presumably they're not
01:33:40.140aware of it but is it that they saw more reps is it that their eyes are better at picking up the
01:33:46.580cue sooner as the as they see the hand of the pitcher like um what do you think so i i don't
01:33:53.480think anyone knows the answer to that question but certainly it has something to do with experience
01:33:59.020it probably doesn't only have things it's probably not only sure um experience but certainly lots and
01:34:05.800lots and lots and lots of practice and repetition for sure that's how every skill is built like
01:34:10.700think about exercising so this is another example that i find really interesting like
01:34:15.020if you wanted to get faster at running a mile you would run that mile over and over and over again
01:34:22.440you would you would train to to do the same thing and you would do it over again as many times
01:34:28.080as you needed to to get to the speed that you physically could manifest basically that means
01:34:34.660you're becoming more efficient, more metabolically efficient with practice. That's what athletes do.
01:34:40.180But what if you're exercising to burn calories? Or what if you're exercising to remain healthy?
01:34:47.980Then you do something like interval training, where somebody's calling out to you every 30
01:34:53.520seconds. You don't know what they're going to say. It's changing things up every 30 seconds.
01:34:57.720That's much more metabolically demanding way of exercising, because your brain can't predict
01:35:02.880what's coming next so you're always adjusting adjusting adjusting adjusting learning processing
01:35:10.160prediction errors is more metabolically expensive on all things considered than when your motor
01:35:17.440actions arise from your predictions so every skill is built by practice you can't become skillful at
01:35:26.740something without practice but that doesn't really account for why some people need more practice
01:35:31.240than others. Like I, no matter how much practice I ever had, I will never play baseball like a
01:35:36.900professional, you know, athlete would play baseball. So I think, again, I would say the value,
01:35:43.960Peter, of a new theory is not that it explains everything. It's that it asks questions that
01:35:52.580have never been asked before. And it sets aside some questions as, you know, sometimes progress
01:35:58.860is asking better questions. It's not answering old questions. So I don't know the answer to your
01:36:04.460question. But what I will say is that practice repetitive feed, you have to have practice and
01:36:10.960you have to have concrete repetitive feedback. Practice alone without concrete repetitive
01:36:17.540feedback is not usually useful for building a skill. And this is also true about emotion.
01:36:24.300You know, if you want to become more granular in how you experience the world or how you experience other people, you can learn to do that just like you would build any other skill.
01:44:11.060No, no. So, I mean, our brains are not more developed. Our brains are differently developed.
01:44:17.160You know, our brains are, we have exactly the size of a, you know, our cerebral cortex are not like larger than what you would expect for a primate of our size.
01:44:31.080I mean, primates have a larger, larger proportion of the cerebral, larger proportion of the brain is the cerebral cortex than for other, for some other mammals.
01:44:40.880That's an innovation that comes with primates.
01:44:45.220And there are other animals that have much larger cerebral cortexes than we do, like an elephant, right, or a whale.
01:44:51.740So what is unique neurobiologically about humans relative to others?
01:44:56.360Yeah, so I think one thing that's unique is, it's probably not the only thing, but one thing that's unique is our capacity for abstraction.
01:45:05.880And that you can see the evidence for, or maybe not evidence, but the anatomical substrate for that you can see.
01:45:13.600So if you were to take the cerebral cortex off the rest of the brain and lay it out flat
01:45:20.220like a napkin, what you would see is that there's an architectural gradient there.
01:45:27.100And the architectural gradient is mostly in the upper layers, and it kind of looks like
01:45:33.720this, that like when you're at V1, so you have like at the outer part, you have V1,
01:45:48.080And there the neurons are very small and they have fewer connections to each other. So there are a
01:45:57.120lot of neurons, but they're very tiny. I'm talking about pyramidal neurons mostly, and they're not
01:46:02.200very well connected. So they're processing small details. And at the other end of the gradient,
01:46:07.460And, you know, in the midline, in the areas that are closest to the subcortex, which we would call limbic, there are fewer neurons, but they're honking big, and they have a ton of connections.
01:46:17.700So the thickness of the cortex is the same, but the constitution of the architecture is different.
01:46:25.220You go from a lot of little cells to fewer, to fewer, to fewer, to fewest.
01:46:31.880There's also a temporal gradient, but we would call that dimensionality reduction or compression.
01:46:37.460So signals are being compressed, or you could say they're being decompressed.
01:46:41.980So what is unique about a human brain, or not unique, but what is special about a human brain is that our ability to compress is greater.
01:46:52.120We have a lot more, that gradient is sharper in a human than it is in any other animal, even our closest relatives, like a chimp or a gorilla.
01:47:06.160Because what it lets us do is it lets us see similarity in differences.
01:47:12.340It lets us treat, you know, a cup and a pail and your hand as something to drink out of.
01:47:26.660It lets us see a kitty cat and a tiger and a cool guy all as cats.
01:47:36.160It lets us, right? So what a chimp can do is a chimp can probably understand that a monkey climbing a tree and a snake climbing a tree is both climbing. They're both to climb.0.94
01:47:53.200And it might even understand, like, a human climbing, like, literally climbing up the stairs is the same as climbing, whereas I think probably a macaque can't do that.
01:48:03.680They probably, climbing the stairs and climbing a tree would be seen as different actions.
01:49:23.500I mean, like, basically, there are many, many, many things that exist because humans collectively, we impose functions on things that they don't have by their physical nature.
01:49:37.280But if we impose them collectively and they dictate our actions, then they do have those functions, like money.
01:49:45.520I want to go back to this idea of chronic stress, right? Because at the end of the day, what I think matters is our experience, our subjective experience. I mean, we've already touched on the idea that I think we both believe, which is the state of one's mind can impact one's health or vice versa, right? We don't, I shouldn't infer the causality like that.
01:50:09.480But let's just say that there is a relationship between the state of mind and the state of health. And by the way, even if there wasn't, why would we want to suffer, right? Why would we want to suffer in our, as David Foster Wallace calls it, the tiny little skull-sized kingdoms on our shoulders, right? Like why? We don't want to suffer.
01:50:30.660I think there are a couple of things that I would, a couple of caveats that I would make. First of all, there's a difference between discomfort and suffering. I can think of lots of reasons why I would, I would deliberately engage in discomfort every goddamn morning. Yeah, exactly, exactly, exactly. Or, you know, I don't know, learning to play piano or learning, doing a PhD or whatever. There are lots of reasons.
01:50:53.700Yeah, or getting your kid out of bed in the morning when they don't want to.
01:59:52.880You will, you know, more likely coordinate your heart rates.
01:59:56.300This is something people do when they trust each other, when they like each other.
01:59:59.940We can also disrupt each other, right?
02:00:02.300So one of the things that's happening for a little kid who's in an abusive situation is that they're not getting the benefit of that kind of savings that most of us who are in safe environments, you know, benefit from without thinking about it.
02:00:24.140But how does that translate to the metabolic deficit, right?
02:01:34.980Bad health outcomes. So it's like a slow drip on a pipe. One drip is not going to do anything.
02:01:43.000You know, a hundred drips, not going to necessarily do anything. But eventually,
02:01:47.220if it goes on for long enough that drip will bore a hole in a steel pipe and or you know monkeys
02:01:55.020jumping on a bed or whatever you know like like eventually the bed will break maybe not the first
02:01:59.560time maybe not with the 10th monkey maybe not with the 20th monkey but eventually it will break
02:02:04.220and so i think that's the way to think about it that it's a slow slow process so chronic stress
02:02:11.600might make you feel like shit, but it's not actually going to harm your health
02:02:16.960immediately, but it will inevitably harm your health eventually.0.97
02:02:24.600So how do we turn that into a prescription? So let's just now talk about a situation where
02:02:31.180uncertainty and helplessness take a different form. It's no longer something as dangerous
02:02:37.540as an abusive parent. It's uncertainty about a job. It's uncertainty about a relationship.
02:02:44.480It's uncertainty about the world we live in. AI, you pick, you know, we could all come up with
02:02:49.680many things to be uncertain about and to also have some degree of helplessness about that
02:02:54.300certainly would never rise to the level of trauma or traumatic insult. And yet two entirely
02:03:00.540different people can be faced with the same set of external circumstances and have a totally
02:03:06.800different manifestation of this notion of chronic stress. So one, I'd like to understand a little
02:03:12.000bit why that's the case. And perhaps more importantly, what can the person who is having
02:03:17.100a more negative response to that do in order to shift the balance and take that metabolic
02:03:24.180cost off their shoulders? Well, the first thing I would say is that I don't think we have to
02:03:30.800imagine what it's like to live in uncertainty. I think modern life is designed to bankrupt a
02:03:39.480human body budget. And we're not equally all affected by these things, but we're all affected
02:03:45.200in one way or the other. And even people who think that they are immune are not immune, right?
02:03:52.100So in the popular press, you see people talking about, you know, fight and flight circuits and
02:03:57.560how they're overworked. And that's why everyone's so stressed. There are no fight or flight
02:04:00.680circuits in your brain. You don't have fight or flight circuits in your brain. Your periaqueductal
02:04:04.720gray doesn't contain fight or flight circuits. It contains circuits for regulating your autonomic
02:04:08.800nervous system. And it regulates your autonomic nervous system throughout your entire life.
02:04:16.160And of course, during moments of threat, it's very active. But we have done these experiments
02:04:23.200where we have people do a memory test where they have to remember one thing, and that modulates
02:04:31.380the periaqueductive ray, these so-called fight and flight circuits, too. It's like the task is
02:04:36.800easier than remembering a phone number. There's no stress involved in the conventional distress sense,
02:04:42.560but yet you see these circuits being active. So I would say there's tremendous amounts of
02:04:50.040uncertainty combined with the fact that our niche is much bigger. Like the things that concern us
02:04:57.120that affect our metabolism is much bigger than it used to be because of the news and because of the
02:05:03.640internet and so on and so forth. So we've got expanded niches, like an expanded potential
02:05:09.700burden, expanded uncertainty. So a lot of expanded cost. And so people are more vulnerable
02:05:16.660to metabolic illnesses of all sort. And my prediction would be, you know, I hate making
02:05:22.680predictions, but I will predict this because I won't be alive to see the result. But I think in
02:05:27.340a hundred years, if we still exist as a species, somebody is going to look back at this time and
02:05:31.380just see it as a massive public health crisis, right? Where we're basically all bankrupting
02:05:38.060our body budgets at the same time as we don't sleep enough and we eat pseudo foods, you know,
02:05:45.020And like anything that's not on the periphery of a supermarket, you know, and we're doing all these things, each of which is sometimes a nudge and sometimes a massive shove in a particular direction.
02:05:59.560So. That I feel very comfortable making that prediction.
02:06:03.400Your question about like, well, why are some people more susceptible?
02:06:13.200Adversity is the potential for something negative to, you know, but there are people who experience adversity and who are not stressed and they're like subjectively.
02:06:23.420And there are people who experience stress.
02:06:27.500They're experiencing things as adverse that like the mythical average person wouldn't.
02:06:33.140All I can say there is it has something to do with prediction and memory.
02:07:58.640the right if somebody something happens to somebody's ear right they they can't hear for a
02:08:04.020while they have to like adjust i mean think of it like uh when you get your teeth fixed and then
02:08:10.820your tongue is like constantly probing at the you know it's because it's trying to forage it's
02:08:16.760learning and it will wire itself eventually to whatever is new and different if you have an
02:08:25.500illness in the like say you have literal tissue damage in the body and that's a that's a metabolic
02:08:34.720burden right there just the healing right that means the brain doesn't have necessarily the
02:08:40.800resources that it needs so that when those signals disappear the brain is still predicting
02:08:47.140that it's going to receive them because it's not updating it's not learning because learning is
02:08:51.880expensive. That's chronic pain. That's pain that is not, pain is real, but the tissue damage is
02:09:00.540gone. But you don't feel pain in your body. You feel pain in your brain. You feel everything in
02:09:05.240your brain. You see in your brain. You hear in your brain. All of your sensations are in your
02:09:09.880brain. You know, you pinch yourself. You don't feel it here. You feel it here. So I think that
02:09:17.760One source of individual difference is you have an adaptable nervous system, you have an adaptable body, you have an adaptable immune system. That means it learns. And each of us come to these external circumstances with different learning histories. That means we're wired. I mean, we are wired by our experiences.
02:09:42.340not i mean they're i mean it's not i'm not saying that we're blank slates or anything like that but
02:09:48.180people come to a situation prepared to experience it in a particular way everything you experience
02:09:59.020everything you do is a combination of the remembered past and the sensory present if
02:10:04.140you don't have a remembered past and your brain can't cobble together bits and pieces of the past
02:10:09.420to make a prediction you will be experientially blind in the moment you just won't it's just be
02:10:15.380noise to you but how do we change that so let's everything you're saying makes sense and if i'm
02:10:23.260in a situation where i i am just manifesting i'm just making up this example i just i get so anxious
02:10:31.980under a certain circumstance that you wouldn't get upset about because you bring a different
02:10:37.400history, a different memory, a different pattern, a different recognition to that system. But I bring
02:10:43.860this very negative experience and I have good reason to because of whatever happened in the
02:10:49.440past. But now I want to change that. I don't want that to be my experience anymore. What can I do?
02:10:55.500So one thing that you could try to do, which won't be very effective, is you could try to
02:11:00.900reach back into your past and change your past. Because who are you right now? You're a combination
02:11:05.580of your remembered past and your sensory present.
02:11:08.660So one way to change your current experience
02:14:14.760So I would look at the baby as we were passing by it and I would think about the baby and I would have a moment of awe, you know, and then I moved on to things like, you know, the sound of the waves, you know, beautiful flowers, the crickets at night, you know, really loud crickets at night.
02:14:33.380And then eventually, that became easy. So then I started to try, like, well, how about a weed? Or how about a weed popping out of a cracked sidewalk?
02:14:47.900a weed a dandelion poking its ugly little head out of a cracked sidewalk can be a moment of awe
02:14:58.760if you understand it as nature's power to be unconstrained by human attempts to control it
02:15:06.080now it's very easy for me to experience a moment of awe when i most need a break like when my
02:15:16.440nervous system most needs a break. For example, you know, I'm about to take an important meeting.
02:15:25.880I'm stuck in traffic. I'm about to take an important meeting on Zoom and my computer fails.
02:15:32.080Or, you know, a meeting where I really can't lose my temper, you know, where I really have to be
02:15:39.440cruel. Or, you know, a time when, you know, I'm sleep deprived and my, you know, little kid is
02:15:47.560doing something to drive me batshit crazy. You know, these are all moments where if I can just
02:15:53.340get a little distance for two seconds, I can take a breath, metaphorically speaking, and then I can
02:15:58.700come back into the fray. And what are you doing? Are you picturing the dandelion? Are you going
02:16:03.900back to no i'm finding a moment like for example if our internet failed right now and i would as i
02:16:11.480often do i would be like well it's miraculous that we can even talk to each i don't know where you
02:16:17.140are peter i'm imagining you're on the west coast i'm on the east coast that means no you're not
02:16:21.620okay well wherever you are the point being that we could be thousands of miles away from each other
02:16:27.560and but we're talking to each other like we were in the same room so yeah when it fails it's
02:16:33.400frustrating, but the fact that we even get to do it is like amazing and awe-inspiring. So no,
02:16:38.020I find something in the moment to be in awe about, you know? And how long did that take?
02:16:45.260Well, I'm giving... No, no, this is a very important example and I really like it.
02:16:49.760How many weeks or months did it take to rewire? It took a couple of months. It took a couple of
02:16:55.760months of daily practice. The thing I would say about having more control and more agency
02:17:00.220is that first of all, it doesn't look the way you expect it to look. You expect, you know,
02:17:08.660you expect to be able to just in the moment, do it. You can't, it requires practice. Like I was
02:17:14.600just telling somebody yesterday, you know, like who wants to just stand up and give a lecture.
02:17:18.780I'm like, yeah, I can stand up and give a lecture after I've practiced it 30 times.
02:17:22.920Like it looks like I'm talking off the cuff and I am in that moment, but it's all automated. I've
02:17:27.560practiced it already a ton of times. So you can take advantage of that. The control looks
02:17:34.780different than you expect. It's harder to get than you expect. And not everybody has the same
02:17:42.760opportunities as everybody else. So some people have more options for controlling and for changing
02:17:50.980things. But even a monk who is being tortured can do it. That means that we all, all of us,
02:18:02.380even in the most dire moments, we all have a little, a smidge more control over how we
02:18:10.560experience ourselves in the world than we think we do. And in some moments, all you really need
02:18:20.700is that little smidge you know in some moments it's that's good enough and in other moments
02:18:26.640when you have a little bit more energy you know you can practice lots of different you practice
02:18:33.380basically making meaning differently you practice so for example i every morning i get up and i have
02:18:42.280to walk by my office to get to the gym and the temptation is so always there i'll just look for
02:18:49.380a minute. I'll just look for a minute. I know I won't just look for a minute. The minute I start
02:18:53.400looking at my email, I'm going to be there for an hour, right? But every morning I am practicing
02:18:58.560not doing the thing that I feel compelled to do in order to do the thing that I know later I will
02:19:07.240be glad that I did. That is, you know, in the moment it's trivial, but the practice in being
02:19:18.340able to do it. And you think everyone is capable of that? I think everyone is capable of that.
02:19:24.760I think everyone is capable of something like that. So what, I'm not disagreeing with you. I'm
02:19:30.560not agreeing or disagreeing with you, but I want to know what you would say to the person who's
02:19:35.460listening to us who doesn't, because you and I, I think are both cut from that same cloth, Lisa.
02:19:41.000I've always chalked it up to, well, yeah, let's just say this. So someone's listening to us and
02:19:47.280they're saying i don't have that gene lisa i i don't have the willpower what you're describing
02:19:52.200sounds like willpower to me and how would you correct them in their thinking here's what i
02:19:57.040would say first of all no willpower is this is just based on empirical evidence like how do you
02:20:02.840build a skill it has nothing to do with willpower willpower is putting a bowl of potato chips in
02:20:07.860front of yourself and trying not to eat it what i'm talking about is getting rid of that like
02:20:12.680you construct your niche so that you don't have to deal with the bowl of potato chips if you want
02:20:18.540to change how you feel in the moment you can either change your remembered past you can change
02:20:23.060your sensory present or you can move in some way which usually involves changing your sensory
02:20:28.880present but like that's pretty much it but what i guess in the end i'm a scientist and what i would
02:20:35.040say is the following i have emails from like i have received more in excess of like 10 000 emails
02:20:47.520from people who have read both of my books and have found ways neither of those books gives
02:20:56.940people advice on how to use these scientific findings in their own life but they do these
02:21:04.620people write to me with stories about their own lives and how they've used it and how
02:21:12.820hopeful, how it gave them a sense of agency and a sense of hope. I've had people write to me
02:21:20.380from a battlefield, like on a battlefield, like in the middle of a war. I've had people who've
02:21:29.780written to me, like all walks of life, all kinds of people. And I will also say that we used,
02:21:38.660I mean, how I came to any of this, right? How I came to any of this. I mean, I study emotion and
02:21:44.100I had a lot to say about emotion and the brain and so on and so forth, but all of the work on
02:21:50.500metabolism and meaning making and all of that came later. Have any of the people who have written
02:21:57.660to you used any of what you've written about through the lens of grief. So you talked about
02:22:05.420your personal experience where you have a much better capacity to manage your emotions in
02:22:11.860distressful situations. And part of it is making sense of it, finding awe in, hey, like I know the
02:22:18.120internet went down, but the fact that we have internet's amazing. But now when someone loses
02:22:23.040their child, loses their spouse. I mean, it's grief to the highest extent. Tell me how you
02:22:31.260think about reducing suffering in that state. Yeah. So I think that when I'm talking about
02:22:37.680the brain's meaning-making capacities, I'm not talking about grand things like finding the
02:22:44.200meaning of life or explaining why someone dies or things like that of a teleological nature.
02:22:52.280I'm talking about things like, what does a set of sensory signals mean?
02:22:56.980So the thing about grief, the thing about losing someone that you love, is that you are losing a source of body budgeting impact.
02:23:10.960Like, we regulate each other's nervous systems.
02:23:13.920My daughter, when she was a baby, was regulating my nervous system as much as I was regulating hers, maybe more.
02:23:20.220And when you lose someone you love, it can feel like you've lost a part of yourself and you have. You've lost body budgeting support. You've lost somebody that you are physically connected to in some way. That's what love and safety is.
02:23:40.060If you feel safe with someone or you make someone feel safe, you create an environment for them to feel safe, you are physically linked to that person in a way that is not necessarily metaphorical, really, in that they had an impact on your metabolism and you have an impact on theirs.
02:24:09.740It will affect her mood. Right. I mean, powerful words and actions in relation to other people are powerful. So you when you lose someone, you've lost that and you feel it. Now, that doesn't explain why they died. It doesn't make it seem any more fair that they died.
02:24:29.400But it does help you understand what those sensations mean and that they eventually will, in like, I would say the evidence is something like 70% of people who don't experience complicated grief, you know, they will go away.
02:29:11.560And I've, you know, we're very close and we talk to each other, like text, you know, like all the time. And, you know, we don't live in the same city anymore. But, you know, like this morning we had breakfast together on Zoom and whatever. So we're close. And there's always been something to love at every age, like something new, something miraculous.
02:29:31.440But I do miss that. I do miss that little girl. I really do. And sometimes I really, I really miss that little girl where, you know, she just wanted to be scooped up. She had her hands in my hair, you know, and we'd be talking to each other. Sometimes I really miss that.
02:29:51.580So tell me, though, what is that feeling is predicting what?
02:29:55.860How do we bring this full circle to the model?
02:30:00.960This is why thinking and feeling and perceiving are not that different from each other because they all are rooted in predictions, which are memories.
02:30:10.840Predictions are your brain reinstating patterns from the past for the purposes of the present.
02:30:16.100like when you when i'm reading a memoir i'm not literally reading what's happened to someone i'm
02:30:23.140reading how they experienced in that moment what happened to their experiences in that moment of
02:30:28.880whatever happened to them in the past when you have a memory you're not literally remembering
02:30:33.980what happened you're remembering your memory is creating an experience in the moment which is
02:30:40.900informed by some set of signals from the past. And this is also, I think, a very powerful,
02:30:50.280powerful insight that you can use, that you can use. Memories are not like files in a file drawer.
02:30:59.160They are not veridical. You are always reconstructing them. When you remember something,
02:31:04.920whether you have an experience of remembering or not, you are reconstructing something.
02:31:10.400You're constructing a set of signals that bears some resemblance to the past or bits and pieces of the different pasts that your brain put together.