Welcome to the huberman. Lab podcast. We discuss science and science based tools for everyday life. I'm Andrew huberman, and I'm a professor of neurobiology and Ophthalmology at Stanford school of medicine. Today. I have the pleasure of introducing. Dr. Robert, sapolsky. Dr. Sapolsky is a professor of biology and neurosurgery at Stanford University. His laboratory has worked on a large variety of topics, including stress hormones, including test.
Tyrone and estrogen and how the different members of a given species interact, according to factors like hormones, hierarchy within primate troops and how things like stress reproduction and competition impact Behavior. One of the things that makes dr. Sapolsky. He's work. So unique is that it combines elements from primatology, including field, studies with human behavior in essence trying to unveil how humans as Old World primates are
Sold by different elements of our biology as well as our psychology. Dr. Sapolsky is also a prolific author of popular books such as why zebras don't get ulcers. The trouble with testosterone and behave, the biology of humans at our best and worst during the course of our discussion today. Robert also revealed to me that he is close to completing a new book. Entitled determined the science of life without Free Will and indeed we discuss the science of life without Free Will during this episode. We are
So discuss stress and how best to control stress. And how stress controls us at both conscious and subconscious levels. We talked about testosterone and estrogen and hormone replacement therapy, and how those impact our mind, our psychology, and our interactions with others as with any discussion with dr. Sapolsky. We learn about scientific mechanisms, that make us who we are. And today, we also discuss tools and how we can leverage. Those scientific mechanisms in order to be better versions of ourselves.
I should mention that, unlike most guest interviews on the huberman Lab podcast. This one had to be carried out remotely due to various constraints. So you may hear the occasional audio artifact. Please excuse that, we felt that the value of a conversation with dr. Sapolsky was well worth those minor minor glitches. And indeed the information that he delivers us is tremendously valuable interesting and in many cases actionable as well. Before we begin I'd like to emphasize that this podcast is separate from my teaching and research.
Rolls at Stanford. It is however, part of my desire and effort to bring zero cost to Consumer information about science and science related tools to the general public in keeping with that theme. I'd like to thank the sponsors of today's podcast. Our first sponsor is rokka rokka. Make sunglasses and Eyeglasses that are of the absolute highest quality. The company was founded by two All-American, swimmers from Stanford and everything about the design of the sunglasses and Eyeglasses was created with performance in mind. There are several things. I like about Roku.
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Humane meets. I eat meat about once a day in general my lunch or my breakfast consists of some meat. And that meat has to be a very high quality and generally I'll eat some vegetables as well. And then I tend to eat pastas and rice and things of that sort later in the day or in the evening in order to facilitate the transition to sleep. So I'm eating meet about once a day and I always insist that the meat that I eat be of the very highest quality and that the animals were raised and maintained humanely while conventionally raised animals are confined to feed lat.
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At Bell Kempo.com huberman and entering my code huberman to get 20% off your first time order. I'm partial to the rib eyes, or the New York steaks. So on one day, I might have a ribeye the next day. I might have a New York steak. I also really like the meatballs. I'm a particular fan of the meatballs. So again, that's Bell Kempo.com huberman, and enter the code huberman at checkout to get 20 percent off your order. And now, without further Ado, my conversation with dr. Robert sapolsky. Great. Well,
You so much Robert for joining us today. I've been looking forward to this for a very long time. I appreciate
it. Why is glad to be here?
There's an enormous range of topics that we could drill into, but just to start off. I want to return to a topic that is near and dear to your heart, which is stress. And one of the questions that I get most commonly is what is the difference between short and long?
Term stress in terms of their benefits and their drawbacks. And the reason I say benefits is that obviously stress and the stress response can Keep Us Alive. But stress, of course, can also sharpen our mental acuity and things of that sort. So how should we conceptualize stress? And how should we conceptualize stress in the short term and in the long
term? Well,
Basically sort of two graphs that wanted to draw. The first one is just all sorts of beneficial effects of stress short term. And then once we get into the chronicity is just downhill from there short term because it saves you from the Predator short term because you're giving a presentation and you think more clearly or your your focus is better, all sorts of aspects of that and
and what then want it being an argument is, how long does it take to go from short-term to long-term and with that somewhat arbitrary, but the sorts of chronic stressors that most people deal with are just undeniably in The Chronic range, like having spent the last 20 years daily traffic jams, or abusive boss or some such thing. The other curve that's sort of perpendicular to this is
Dealing with the fact that sometimes stress is a great thing, like our goal is not to cure people of stress because if it's the right kind, we love it. We paid good money to be stressed that way by a scary movie or roller coaster Rod. What do you want up? Seeing is when it's the right amount of stress. It's what we call stimulation and the basic curve there is, here's an optimal level of stimulation.
And too little and function goes down with what we would call boredom and too much and function goes down with what we would call stress. And the optimum is what all of us aim for,
in terms of the benefits of stress in the short-term. One thing that's really striking to me, is how physiologically the stress response looks so much, like the excitement response to a
to a positive event and we can speculate that the that the fundamental difference between short-term stress and short-term excitement is some neuromodulator like dopamine or something like that. But is there anything else that we know about the biology that reveals to us? You know, what, what really creates this thing? We call valence that an experience can be terrible or feel awful or it can feel wonderful exhilarating depending.
This somewhat subjective feature we call valence. What do we know what valence is, or where it
resides on a really mechanical level? If you're in a circumstance, that is requiring, that your heart races and your your breathing as fast and you're using your muscles. And some such thing. You're going to be having roughly the same brain activation profile. Whether this is
Is for something wonderful or something terrible with the one exception being that if the amygdala is part of the activation, this is something that's going to be counting as adverse weather that the circumstance and adverse circumstance recruiting the amygdala into it and how much it's the amygdala being involved biases you towards, you know, interpreting it as even more awful, the amygdala in some ways this kind of the checkpoint as to whether we're talking about.
Out, excitement or Terror?
Let's use the amygdala as a transition point to another topic that you've spent many years working on and thinking about, which is testosterone and other sex steroid hormones. I heard you say. Once before that, among all the brain areas that bind testosterone that you know, where testosterone can park and create effects that the amygdala is among the
The the most chock-a-block full of these parking spots. These receptors. I realized there's a lot here, but how should we think about the role of testosterone in the amygdala? Given that the engagement of the amygdala? Is fundamental in this transition point between a exhilarating positive response and a A- stressful response or maybe just broadly, how should we think about testosterone and its effects on the brain?
And pertinent to the transition from whether this is a stressor, that's evoking fear or revoking aggression, in terms of that Continuum also because the amygdala is in the center of all four points on those axes. Basically, almost everybody out. There has a completely wrong idea as to what testosterone does, which is testosterone makes you aggressive, because males virtually every species out there of mortis.
Stas thrown in a more aggressive and seasonal meters have testosterone surging, at the time of year. They're punching it out over territory and and you take testosterone out of the picture. You castrate any mammal out there including us and levels of aggression will go down and the easy thing. Then tends to include to conclude the testosterone causes aggression and the reality is testosterone does no such thing.
Doesn't cause aggression. And you can see this both behavioral and in the amygdala. What does testosterone do it lowers the threshold for the sort of things that would normally provoke you into be so that it happens more easily. It makes systems that are already turned on turn on louder rather than turning on aggressive music or some such thing. What does that look like? Behaviourally? You take five?
Male monkeys, put them together. They form a dominance. Hierarchy. Number one is great. Number five is miserable. Number three is right in between that, take number three, and shoot the guy up with tons of testosterone and he's going to be involved in more fights, aha testosterone, uniformly cord causes aggression, but you look closely and there's a pattern to it is. Number three, now challenging numbers, two, and one for their place in the highwomen.
Absolutely not. He is brown-nosing them exactly as much as they used to what's going on. Is he's just a miserable Terror to poor number four and five. And in that case, what testosterone is doing, is amplifying the pre-existing patterns of aggression and amplifying the social learning. This work has gone into it. Now. I'm sort of the more productive level. So how does that translate into the amygdala does testosterone make
Amygdala neurons, have action potentials. Does it cause those neurons to suddenly speak about fear and aggression? Spontaneously, absolutely not. What they do is if the amygdala is already being stimulated, it increases the rate of neuronal firing what it was worth it. It shortens after hyperpolarization. So the theme there exactly is it's not creating aggression. It's just upping. The volume of what
To aggression is already there. And once you factor that in, you know, it's impossible to say anything about what testosterone does outside, the context of what testosterone related behaviors, how they get treated in your, in your Social
Survey. And in terms of status, and the relationship between individuals, either non-human primates or humans. Can we say that testosterone and levels?
Of testosterone or I should say, can we say that relative levels of testosterone between individuals is correlated to status within the hierarchy.
Yes, but in a way, the winds up being totally uninteresting. Like you go back. I know. Whatever number of decades to Endocrinology texts and they were two, totally reliable findings in there. And see I have a dog and here, that's
so good. We like dogs at The huberman Lab podcast.
Jingling a bit. They are welcome. They are. Absolutely welcome. Yeah. And their Beach to truisms Which is higher levels of testosterone.
Your own project higher levels of aggression in peonies and other animals, higher levels of testosterone predict higher levels of sexual activity. Whoa testosterone causing bow, and the correlation is there and when you look closely we could cause and effect stuff sexual behavior raises testosterone levels aggression raises testosterone levels your levels before had or barely predicted what's going to happen, so it's over.
Response rather than a cause when you Loop it that though, in terms of making sense of individual differences. They don't matter a whole lot. You can like spend an entire career on the social circumstances that produce, three and a half percent more testosterone than the circulation and expect to see all sorts of interesting implications. And that's not really the case. It's somewhat of a
Yes, or no, modulator of the much more subtle social stuff that's already there.
Very interesting. You know, I think that there's a, there's a lot of misconceptions about human biology, but testosterone seems to be one area where, at least from what I can find on the internet. There's a sort of at the peak of misunderstanding, maybe we could just ask a few more questions about testosterone and sexual behavior, because there's an interesting story there about caste.
Raishin versus non castration and the causality again. But before you address that, I just want to highlight something that you said that I think is so vital, which is that behaviors such as aggressive behaviors and sexual behaviors can actually increase testosterone. I did, I hear that correctly and the reverse is sort of true but not but not in a causal way. Is that set right
the opposite direction? With the causality? Yeah.
Yeah. Yeah, so if I were to
Increase somebody's testosterone by 30 percent male or female doesn't matter that their sexual behavior may or may not change
essentially, Zero Effect at all. Your brain is not that sensitive to fluctuations and testosterone levels in terms of things like aggression, raising testosterone is a great footnote. If you have the right type of willing to die in the trenches devotion sort of thing, watching your favorite team. Play a sport will raise.
Your testosterone levels as you sit there with a potato chips in your armchair. So it's not the physicality of aggression. It's the psychological framing of it. So yeah, testosterone is not causing that and a great way to appreciate that. Is okay. See you at all these testosterone sexual behavior correlations and you do the definitive endocrine Intervention, which is you do.
Was subtractions that you've removed the testes. And as I said before levels of sexual behavior goes down good. We've just shown that testosterone is somehow causes. Critically they go down but not down to zero whether you are a rat or a monkey or a human whatever and what predicts how much residual sexual behaviors there, how much sexual behavior there was before castration.
And what that's telling you is by then that's Behavior. That's being carried by, social learning and context rather than by a hormone. Exact same thing with aggression. Drops. After castration doesn't go to zero, the more prior history of it, the more it just keeps coasting along on its own even without testosterone.
Very interesting is can we say that there's an exception in terms of the early organizing effects of hormones? Like, for instance, if a
Whooping animal is deprived of testosterone or estrogen, or aromatized testosterone into estrogen. You know, there's a whole story there is, you know, but then I could imagine that the circuits of the brain that are responsible for initiating sexual behavior in the first place, might not emerge and therefore, not be sensitive to testosterone later in life. Is that right? Yeah,
exactly. And a great way of seeing that is this totally nutty biological factoid, which is the second to Fourth.
Digit ratio and hands. Oh, yeah, totally. Obscure thing, the ratio of one to the other in some way, reflects levels of testosterone Anderson exposure during fetal life, and I can't remember which way it goes and its miniscule and you need a thousand people in your sample size to be able to see anything but you see it in other primates. It's already there and Fetal sonograms all of that. So that's a readout.
Out of subtle differences in prenatal exposure. And that winds up being a predictor of a whole range of sort of stuff and adult Behavior. So yeah. At the fetal end, when you're still building, everything testosterone in the amount of it is making a huge difference. By the time, you're an adult. It's just, you know, somewhat of an all-or-none
signal. Yeah, I could have a confession, which is that I was a master student at Berkeley and Mark breedlove's.
Inna. So I'm an author on that paper. Although I'm deep within the author line and you got the description of it. Exactly. Right. That it's the D to the index finger, to the ring finger ratio is more similar in females. And then it is in males and males. They index finger tends to be shorter and for people out there who are listening to this, who are now freaking out or measuring, think that there's a proper way to measure this which is it eyeballing. It doesn't work all the time unless at the extremes and there's some really
Kissing stories there. It actually has been replicated. No fewer than five times Mark, Breedlove tells me. But yes, in terms, in terms of these early organizing affects. Those are very seem, very robust in most studies. These later, effects are sort of, activation of neural circuits by hormones. I'm absolutely fascinated by this and if we, I do have a couple other questions, which, which is we normally associate testosterone with males, but of course, females make testosterone.
As well from the adrenals and, and presumably elsewhere to. I'm guessing if we looked hard enough, we'd probably find that there were other sources of androgens in females. It, can we say that the that these General Contours of effects on on aggression, but also pertain to females? And, and I suppose I should ask in particular about female female aggression, which does exist in many species, female male to aggression as well as maternal aggression, which is a row.
Lost aspect of our evolution, of course that the mother will an angry mother animal of any kind protecting. Her young is truly dangerous in the best sense of the, of the
word. And that type of, you know, post-party Rishon period after birth, aggression is all about estrogen progesterone. Those sorts of things, female aggression. The rest of the time has testosterone as a major player at a much lower.
Lower level on the average on the average, one always has to say, but it's basically the same punch lines in females. The lower levels of testosterone are essential for typical levels of aggression and sexual behavior. Nonetheless. They're not causing it. It's not sensitive to small individual differences. Same exact thing, you can get way over impressed with the importance of androgens and females just as readily as in males,
so
In line with that, how should we conceptualize testosterone? All right. I realize there isn't a single sentence or that can capture a hormone in all its effects because hormones have so many different slow and fast effects on the brain, on other glands, on their own, on the very glands, that produce them. But as I've heard you talk about testosterone today and over the years, I start to get the impression that as the most misunderstood molecule in human health. In the universe, it has
It's clearly doing something very powerful. It's Shifting the way that certain neural circuits work adjusting the gain on the amygdala as you described and and certainly other things as well. Is there any truism about testosterone like and its relationship to effort or its relationship to resilience and in a way that maybe will help me and other people sort of think about how to think about testosterone.
Yeah.
Maybe three separate answers to that. The first one is, I think it's a fair summary to think that when it comes to motivated, strong behaviors. What testosterone does is make you more of whatever you already are. And that to me, sexual arousal, libido aggressiveness spontaneous aggression, reactive aggression, things of that sort. It's upping the volume of things that are already strongly there.
Second way to think about it is.
Well, here's here's like my favorite finding about testosterone, and this, this was some wonderful work by a guy. John Wingfield, who's one of the best behavioral endocrinologist out there and about 20 years ago. He formulated what was called The Challenge. Hypothesis of testosterone action. What does testosterone do? Testosterone is what you secrete. When your status is being challenged and it makes it more likely.
That you'll do the behaviors needed to hold on to your status. Okay, so that's totally boring, the straightforward if you were baboon. If somebody is challenging, your high rank, the appropriate response on your part is going to be aggression. All right. So we've just got in through the back door to stop streaming than aggression again, but then you get to humans and humans have lots of different ways of achieving or maintaining status. And all you need to do is go to like some fancy private.
It school's annual auction and you will see all these half-drunk alpha males competing to see who can give the most money away as a show of conspicuous, like, you know, property that they have. And in a setting like that. I mean, I've haven't been able to take urine samples if there's times, unfortunately, but that shows the flip side of it, if you have a species that hands up status in a very different sort of way.
A testosterones could have Boost that also. Okay. So that generates a totally nutty prediction. Wow, take people in a circumstance. They playing an economic gain where you get status by being trustworthy and being generous in your interactions with the game. If you give people testosterone, does that make them more generous? And that's absolutely the case. Totally cool finding showing you. I don't know. Basically if you took a whole
Whole bunch of Buddhist monks and shot them up with testosterone. They'd get all competitive with each other as to who could do the most random acts of kindness. And if we have a societal problem with too much aggression, the first culprit to look at is not testosterone. The first to look at is that we hand out so much damn elevated status for aggression and so many circumstances. So I find that finding to be fantastic. Third.
About subtlety of testosterone. Okay. So like some subtler, behavioral effects, you give testosterone to people and they become more confident. They become more self-confident. Well, that's good. People. Pay to take all sorts of nonsensical self-help courses, that will boost your self-esteem. And that's a good thing. And less testosterone makes you more confident that is inaccurate and you're more likely to Barrel into wrong.
Decisions. What shown in economic game play is that stops room by making you more confident. Makes you less Cooperative because who needs to cooperate because I'm on top of this. All on my own testosterone makes people cocky and impulsive and that may be great in one setting, but if in the others, you're absolutely sure your army is good over on the other country, in three days. So he'll let's start World War one and you get a big surprise out of that test.
Austrian altering risk, assessment beforehand, probably played a big role in that kind of miscalculation
super interesting. I always think about testosterone and dopamine being close cousins in the brain. Not just because of their relationship through the pituitary and hypothalamus that, of course, but also, because of dopamine's salient role in creating this bias towards Xterra reception, you know, when somebody takes a drug that increases,
As dopamine or their chock-a-block full of dopamine, they tend with I want to highlight 10 because this is I'm really generalizing here, but they tend to focus on outward goals, you know, things beyond the boundaries of their skin and testosterone seems to do a bit of the same. It tends to put us into a similar mode of perceiving, the outside world in ways that we are asking questions. Like, how do I relate to this? Other of my species? How do I relate to these goals? Is there?
Thing that we can do it, a better conceptualize the relationship between testosterone and dopamine and motivation. Or would that just take us down the the Alleyways of neural Pathways and the hypothalamus? Which is fine too.
Well, I think it's got lots to do with sort of this massive revisionism about dopamine everyone. Since the Pharaohs got brought up being taught. The dopamine is about pleasure and reward turns out it isn't. It's about anticipation.
One of reward and it's about generating the motivation. The goal-directed behavior needed to go get that reward. And before you know it you're using like elevated. Dopamine your entire life to motivate you to do, whatever is going to get you like entry into heaven afterlife, kind of, you know, it's it's doing that sort of thing. So it's really about the motivation and what testosterone does even in individuals who were not aggressive and why?
And replacement is often a very helpful thing for aging, males is increases energy. It increases a sense of their nests of presence of alertness, it increases motivation. So that's a whole aspect, which then takes us into is your motivation to get up and like go, you know, hand out lots of soup in a soup kitchen for homeless people? Or is it to get up and go ethnically?
Glenn's a village. It's got much to do with what your makeup was, before the testosterone caught on board. So it's activating an energetic sense, testosterone within minutes increases glucose uptake into skeletal muscle. You're just more awake and alert and all of that. And that has a lot to do with what dopamine does. And as one might predict, then getting just the right levels of testosterone infused into.
Bloodstream feels great to Lab Rats. They will lever press to get infused into the range that optimizes dopamine release. So there's you're absolutely right there. You're deeply intertwined
and such beautiful biology there and I love the way you encapsulate their relationship. I I want to ask about estrogen and we don't hear as about estrogen as often and it's always interesting to me now, doing some public.
Facing education, you know that testosterone is this very controversial molecule just to say it is almost controversial but estrogen doesn't seem to hold the same controversial wait and yet estrogen has a very powerful effects on both, the animal brain and on the human brain of males, and females men do not want their estrogen to go too low, terrible things happen. They will lose cognitive function. Libido can
So men need estrogen as well, but perhaps, maybe we can put the same filter on estrogen, as we did on testosterone. Are there any general themes of estrogen that are that people should be aware of? Or the you think that are generally? Misunderstood is it really all about feelings and empathy and making us more sensitive? I sense, not
know. And it's once again, very context dependent. And if
Even after giving, birth is playing a central role and you wanting to shred the face of somebody getting too close to your, your kitten's kind of thing. We know, it's not just warm fuzzy, you know, empathic kind of stuff estrogen, you know, in lots of ways could be summarized by if you had a choice in the matter, between having a lot of estrogen in your bloodstream or not go for having a lot of estrogen. It included, enhances cognitions. And exactly as you said,
Stimulates neurogenesis in the hippocampus. It increases glucose and oxygen delivery. It protects you from dementia. It decreases inflammatory. Oxidative damage to blood vessels, which is why it's good for protecting from cardiovascular disease and contrast to testosterone, which is making every one of those things worse. This brings up this Minefield of the question, which is so what about
Menopausal estrogen and all sorts of lab studies, with non-human primates suggested that you keep estrogen levels high, after a monkey's, equivalent of menopause and you're going to keep brain health a lot better or decreasing, the risk of dementia stroke. Every such thing as fugitives, great antioxidant, all of that. So, in the 90s, I think, when
She lie. I'm forgetting her name. But when there was the first female head of the NIH Bernadette Healy set up this massive, prospective human study. What was going to be. The biggest one of all times, looking at the pluses and minuses of postmenopausal, estrogen and tens of thousands of women. This was great and they had to cut the show study short. Because what they were seeing was as
Estrogen was not only doing the normal bad stuff that you expect in terms of some decalcification stuff, but it was increasing the risk of cardiovascular disease and it was increasing the risk of stroke and was increasing the risk of dementia and this ground to a halt and everybody. They stopped the study and front page news and everybody pad point and nobody could make sense of it who had been spending the last 20 years, studying the exact same thing in primates.
And seeing all the protective effects and the explanation turned out to be one of those things where, like, law of unexpected consequences. Okay, menopause in women at last different lengths of time that may be a factor that's going to come. You know, what, let's not start. Giving our study subjects more estrogen until they're totally past menopause. And when you've got that lag time in between, you sure,
Shift, all sorts of estrogen receptor patterns and that's where all of the bad effects come from. Boiled of the monkey studies had involved, just maintaining ovulatory levels into postmenopausal period. If you do that and you get great effects. Estrogen is one of the greatest predictors of protection from Alzheimer's disease. All of that, but it needs to be physiological. Just keep going. What keep continuing with your body has been doing for a long.
Versus let the whole thing shut down and suddenly like try to fire up the coal. Stoves at the bottom of the basement, kind of thing. And get that going there. You get utterly different outcomes. And that caused a lot of human health consequences when people suddenly decided that estrogen is, in fact, neurologically endangering postmenopausal e,
wow, that's fascinating and I never thought that these steroid hormone.
Receptors. Could you know, by not binding estrogen have being devoid of estrogen? Binding? I should say, could then set off a opposite biochemical Cascades fascinating? I guess it raises the question about testosterone replacement to whether or not people should talk to their doctor before too long men and women, talk to your Physicians before too long to avoid these, whatever is happening in these periods where there isn't sufficient testosterone. And or estrogen
Sounds like a good cause longer term problems, even when therapies are
introduced to additional misery / complications. So, okay, you're trying to understand. You look at women with a history with or without postmenopausal estrogen replacement where it's done, right? And you're seeing 20 years later, estrogen is predictor of a decreased risk of Alzheimer's that. Then you got to start trying to do the the unpacking Pros.
Aspect of type studies, how much estrogen, at which times estrogen, which is just a, as a catch-all term, for a bunch of hormones. S trone estradiol sgo how much of each one of them natural or synthetic go. Try to figure all of that out. And the second complication is, it's often hard to say anything about what estrogen does outside, the context of what progesterone is doing and often. It's not the
Levels of either. It's the ratio of the two. This is such a more complicated endocrine system than testosterone and, you know, because you have to generate dramatic cyclicity that like no male hypothalamus ever has to dream of it's a much more complicated system. Thus, it's more complicated to understand let alone like figure out looking ideal benefits are of it.
Yeah, can I don't know what to make of the literature on dropping rates of testosterone and dis and endocrine disruptors. You know, what, I was at Berkeley. When Tyrone Hayes published his data on these frogs that were drinking water from various locations, throughout the United States, not just in California, and seeing very severe, endocrine disruption through blockade or, and of Androgen receptors and all sorts of issues. And you hear this all the time. Now that sperm counts are
Popping that they're all these endocrine disruptors that there's birth control in the water in the drinking water. It all sounds starts to sound a little crazy and yet I've also been fooled before by, you know, I guess a good example would be. There's a lot of crazy stuff in the world online. About all the terrible stuff in highly processed foods. And yet you've got very respectable people endocrinologists at UCSF like Robert lustig saying, yeah, these a lot of these hidden sugars and these emulsifiers they're causing.
Real problems. So I've become more open-minded about the question and so, are we suffering from drops in sperm counts, and testosterone, and estrogen and fertility as a consequence of endocrine disruptors in the in the environment and food or because of social reasons. Is there anything that we can hang our hat on like real data that you're confident? And or is it just a
mess? No. The phenomenon just appear to be quite
Real cross-sectional studies, human populations. Or I still don't understand why. This was one of the first things that has spotted, decreasing, testicle size and crocodiles. Go figure why that was one of the first contributions to this. And I think the phenomenon is absolutely real. And what your then left with is a to Classic challenges, which is this is correlated with something Broad in.
Environmental toxins, which one's how much when etcetera and the other one always being well, okay, dropping is a dropping enough to make a difference. How big of an effect is this? And those are where the juries are still
out. Yeah. It's an area that I know there's a lot of interest in and you've got groups of people who won't touch a receipt at a store because of the bpas that are on the inks of the. And then you got people who don't care about those things. It's it is a family.
Donating area and I hope that more biology will be done there. Soon. I'd like to briefly returned to to stress. You described a study, once about two rats one, running on a wheel. Voluntarily one who's basically stuck in a running wheel and is forced to run any time. Rat number one runs. So in one case the rat is voluntarily exercising and in the other case, the the
The rat is being forced to go to PE class. So to speak. But really and seeing Divergent effects on biology and I'd like to just touch into this and use it as kind of a case study for stress. Mitigation in general. I'm rather obsessed in our colleague. David Spiegel associate chair of Psychiatry at. Stanford is obsessed with this question of how humans can start to mitigate their own stress.
What do you think about stress, mitigation? And and what should we do? As individuals and as families and as a culture to try and encourage people to mitigate their stress, but in ways that are not going to turn us into rat. Number two, where we're being forced to mitigate our own stress and therefore becomes more stressful.
And what you see is rat. Number one gets all the benefits of exercise rap. Number two, gets all the downsides of severe stress with the same.
Exact muscle expenditure and movements going on perfectly yoked great example. That it's the interpretation in your head and I haven't kept up with that literature, but I'll bet you rat. Number two is having a whole lot more activity and it's amygdala than is Rhett. Number one. Okay, so stress mitigation anything I should say here. I should preface with reasonably good at telling
Young people. What's going to happen if they don't manage their stress, but I'm terrible at actually like, managing stress or advising how to manage that. I'm much better with the bad news aspect of it. But what do you see is by? Now, just a classic literature half, a century old, sort of showing, what are the building blocks of stress, not who you step outside and you've been gored by an elephant. And can you grow?
From your experience and what doesn't kill you makes you stronger or not. You could have a stress response. But you're in the realm of the gray zone of ambiguous, social interactions, that sort of thing. Some people have massive stress responses, others. Not at all, in between. Enjoy it. Like, what are the building blocks of what makes psychological stress stressful? And the first one is exactly, is brought up by that running study. Do you have a sense of
Of control, a sense of control, makes stressors less stressful and the running wheel shows that or studies where you you lab rat or you College freshman volunteer have been trained that by pressing a lever you're less likely to get a shock. And today you're at the lever there working away and unbeknownst to you. The lever has been turned off and it has no effect on shock frequency. But because you think you have some control you have less of a stress response.
If you were a rad and doing this day in and day out, you're less likely to get an ulcer. So a sense of control and related to that is a sense of predictability. Rat gets shocked, human, get shocked, whatever. And the scenario either is the shocks come now, and then or the shocks come down and then and 10 seconds before a little warning, light comes on. And then you get the warning light. The shocks are at this stressful. He got predictability.
See, because if you're not getting warning light, any second, you could be a half second away from the next shock, you get a warning light and you know that, if there isn't one you've got at least ten seconds worth of relaxation, you know, what's coming, you can prepare your coping responses and best of all afterward, you know, when you're finally safe, when you can recover from it, and that's enormously predicting protective, the others outlet for frustration.
And you take a rat who's getting shocked, and if it could run on a running wheel, that's protective thing. It's doing it voluntarily. If you've got a rat and a Knopf on a bar of wood, a stressor is less stressful. Unfortunately, if you have a rat or primate, we're human and they're stressed, the ability to aggressively dump on. Somebody smaller and weaker. Also reduces the stress response and displacement aggression.
Explaining the fact that displacement aggression reduces stress accounts for a huge percentage of Earth's like unhappiness. So all of those variables get social support as well. That's a good one interpreting circumstances being good news rather than bed her race. So you've got this very simple sort of like take-home recipe of go out and get as much control and much predictability and as many outlets and as much social support as possible and you're going to do just fine and you go out and do
That and that's a recipe for total disaster because it's much much more subtle than that one. Great example. Okay, so you're getting shocks, you want to warning before hat, get a little warning light 10 seconds before. Each shock is wonderfully protective. Get a warning shot, get a warning light, one second before the shock doesn't do anything. There's not enough time for you to get the psychological benefits of the anticipation. Now, instead get
A little warning coming on two minutes before each shock and it's going to make things worse because you're not going to be sitting there like, you know, reveling and sort of your sense of predictability. And it's soon to be okay. You're going to be sitting there for two minutes saying damn here. It comes predictive information, only works in an Aerodrome. A similarly control. Do you want to have a sense of control in the face of stress?
And the answer is only if it is a mild to moderate stressor because what's happening, then your sense of control is completely independent of the reality of whether you have control or not. But in the face of mild to moderate stressors, a sense of control gets interpreted, as wow. Look how much worse things could have been. Thank God, I have control. I'm on top of the semester. My fate in contrast if it's a major stressor all
That a, you know, arbitrary sense of control does is make you think, oh my god. Look how much better? It could have been. I could have prevented it, and we all know that intuitively. Like we do that in the faces of people's worst stressors. Nobody could have stopped the car, the way, the kids suddenly jumped out. It wouldn't have mattered. If you would gotten them to the doctor a month ago. Instead of now, it wouldn't have made me. You didn't actually have any control.
And what you see is, you absolutely want to have a huge sense of control, over mild-to-moderate stressors and especially ones that result in a good outcome. Hooray for me. And in the face of horrible stressors, what you want to do is like self-deception then like truth and Beauty don't necessarily go hand in hand at that point. And that's why stress management techniques of control and predictability.
You wind up being far worse than neutral. If you're preaching that to somebody homeless or somebody with terminal cancer where somebody who's Refugee, tell the neurotic middle-class person that they have the psychological tools to turn, you know, Helen to heaven. And there's some truth to that do the same thing to somebody who's going through a real hell and that's just privileged, you know, heartlessness to do.
That because that doesn't work or more, you know, Outlets if your Outlets are damaging, that's not a good way to mitigate stress social support. If you're confusing mere acquaintances for real social support, you're going to have the rug pulled out from under you at some point. If you're mistaking, social support for being going and bitching and moaning and demanding supportiveness from everyone around you, rather than you doing some of that. Reciprocally that's not going to work very well either.
You know, it's not simple. It's not for nothing. That lots of us are really lousy it, like being good friends, and things like that and why it takes a lot of work to, like, do it, right? Because you do it wrong, and it may temporarily seem like a great thing. But when it turns out to be completely misplaced, Faith, you're going to be feeling worse than before you
started.
Interesting. These days. There's a lot of interest in using physical practices, to mitigate stress, you know, trying to get out of the ruminating and to some extent, take control of neural circuits in the brain by using exercise, and using breathing and hypnosis. And and of course hypnosis has a mental component as well. What are your thoughts on stress mitigation from the standpoint of? Okay, so we don't want to be rat number.
We want to select something for ourselves. So we have to take take the initiative for ourselves being forced into exercising is not. It could actually have negative health effects, a perhaps. So we need to pick something that we like we need to take control of it in terms of supporting other people you touched on that a bit. What is the best way to support other people? Is it to talk about the stressful thing? I mean, I'm not asking you to play psychologist here, but I find Divergent data on this, you know, we can
Spin ourselves up into a lather by ruminating on something and language. Seems to me like a, it's a wonderful tool, but it's also a fairly deep deprived tool because it doesn't really get into the core of our physiology, like something like breathing would. So what are your thoughts on more for lack of a better way to put it more head, centered cognitive approaches to stress mitigation versus kind of a going at the core physiology. Cold showers now, or even
Nothing to some extent, you know, just to get people stress, acclimated voluntarily taking cold showers, you know,
make some sense, physiologically preconditioning for when the real stressors come in terms of what you bring up. How Transcendental Meditation? Mindfulness, exercise prayer, sort of reflecting on gratitude. All that sort of thing collectively. They work on the
Which they work. In terms of, they can lower heart rate and cholesterol levels and have all sorts of good outcomes, but they come provides us. One is exactly the caveat that comes out of the running wheel study is it doesn't matter how many of your friends swear by the Stress Management technique. If doing it, makes you want to scream your head off after 10 seconds. That's not the one that's going to work for you. So, you know read the fine print in the testimonials, but it's got to be something that works for you.
Other one is the Stress Management type techniques that work. You can't save him for the weekend. You can't save them for when you're stuck on hold on the phone with music for two minutes. It's got to be something where you stop what you're doing and do it or virtually daily or every other day and spend 20 30 minutes doing it. And what you see coming out of that is this like 80/20 rule from economics?
80/20 80% of the complaints in the story, come from 20% of the customers, things like that. What do you see is if your entire life consists of every single thing on your shoulders that you can't say no to 24/7? If you've stopped that and finally said my well-being is important enough that I'm finally going to say no to some of the stuff, but I can't say no to and I'm going to do it every day for 20 minutes. Whatever Stress Management.
Q, then during those 20 minutes short of, who knows what you're already. 80% of the way there. Simply by having decided. Your well-being is important enough that you're going to stop every single day and have that is priority. And that's the exactly the same finding that you find people with, chronic depression, untreated that merely calling and getting an appointment to see a mental health. Professional people start feeling better already because it's evidence.
That you've been activated and you matter enough to do this and you could conceive that this would actually have a good outcome rather than a hopeless one, just doing something meditative or reflective every day or so and it hardly even matters, which one you're doing. And what comes out of that is thus another warning, which is do not trust. Anybody who says it has been scientifically proven that their brand of
Management works better than the other ones. Just watch your wallet at that point.
Amen. I think one of the core goals of my lab and David Spiegel's lab and I know you've worked with David and published papers with David as well is to really try and find out what are the various entry points to this thing that we call the autonomic nervous system and the stress system and the systems, that when gone unchecked really can take us down a dark path, you know, and the idea that there are so many entry points is
Only the one that keeps what the data keep telling us over and over again. So there's no magic breathing tool or exercise. Its any variety of those or one of those. And again we come back to this idea that it's the one that you select in the one that you make space for. And it's the one that you hopefully enjoy, that's going to work. Best in terms of physiology and
there's nine for those people who were stuck around you.
Right? Right. Absolutely. And you know, that brings me to the
Question of, I find it amazing that how we perceive an event and whether or not we chose to be in that event or not, can have such incredible, eat different effects on circuitry of the brain, and circuitry of the body and biology of cells. And in some ways. It boggles my mind. Like, how can a decision made presumably with the prefrontal cortex? Although other parts of the brain as well. How can that change essentially?
Ali. The polarity of a response in the body and I mean you've talked before about type A personalities and that we don't have to go into all the detail there for sake of time but it is interesting that the effects of endothelial cells. I mean, literally of the size of of the portals for blood are in opposite direction depending on whether or not somebody wants to be in a situation as a highly motivated person. Maybe you could just give us the top Contour of that because I think it really
Illustrates this principle so beautifully. And then maybe if you would, you could just speculate on how the brain might have this switch to turn. One experience from terrible to beneficial or from beneficial to terrible. It's really
fascinating. Well, all you need to do is like tonight before you're going to sleep and you're lying in bed, and you're nice and drowsy, and your hearts beating nice and slow.
Start thinking about the fact that you know, that heart isn't going to beat forever and imagine your toes getting cold afterward and imagine the flow of blood coming to a halt and all of you clotting. And if you're, if you're going to be doing something with your physiology, at that point, that 99% of mammals out there, only do if they're running frantically and you're going to be turning on your synthetics response with thought, with emotions with memory in the measure of
That is just how much the cortex and the limbic system sends projections down to all the autonomic Regulators in the brain. You can think autonomic regulatory neurons into action in ways that lie, other animals can do with like extremes of environmental circumstances, given that, and the autonomic role in the other Big Challenge in understanding. It is gigantic and
Visual differences and that's him. You talked about the optimal amount of stress that counts as stimulation and in general that stress that not too severe and doesn't go on for too long and there's overall in a benevolent setting and under those conditions. We love being stressed by something unexpected and out of control and predictability like really interesting. Plot turn in the movie. You're watching. That's great, but you could be
Visual differences that somehow has to accommodate the fact that for some people the perfect stimulatory amount of stress, is like getting up early for an Autobahn bird-watching walk next Sunday morning. And for somebody else, it's signing up to be like a mercenary in Yemen and tremendous individual differences that swamp any simple, you know prescriptions.
Yeah, the the
Prefrontal cortex, this thinking Machinery that we all Harbor. It's such a double-edged sword. And what's remarkable to me is how the areas of the brain, like the hypothalamus and the amygdala, they're sort of, like switches. I mean, they, there's contacts in, there's gain control, you talked about the game to drove by testosterone, Etc, but they're really like switches. I mean, if you stimulate ventromedial hypothalamus, you get the right neurons. And animal will try and kill even an object that sitting next to it. You tickle some other neurons.
Try and mate with that same object. I mean, it's really wild. The I think there are probably rules to prefrontal Cortex. Also, but it sounds like the the context plural from which prefrontal cortex can draw from is probably infinite so that we could probably learn to perceive threat in anything. Whether or not it's another group or whether or not it's science or whether or not, it's somebody's version of the shape of the earth versus another. I mean, it's like you can place
plug in anything to this system and give it enough data. And I think it sounds like you could drive a fear response or a love response. Is that overstepping
or a mixed? Hardly ambivalent one that is changing by the millisecond and like good mutually contradictory. No, that's absolutely the case the prefrontal cortex. I more than once have I regretted having like wasted 30 years of my life studying the hippocampus when I should have been studying. The
Prefrontal cortex because it's so much more interesting what it does and it's all this contextual stuff. It's all the ways in which it's not okay to lie in this setting, but it's a great thing. And another, it's not okay to kill unless you do it to them and then you get a metal. It's not all of this social context and moral relativity and situational ethics stuff. That's the prefrontal cortex. That's got a master that
And that wines that meaning that's place in your brain, more than anywhere, where you say, your perception of things can powerfully influence the reality of what's coming into, you mean, great example, just harking back to testosterone. Okay. So exercise boosts up testosterone levels does exercise and success do it more than exercise and failure of literature back in the 80s or so.
Looking at outcomes of marathons to testosterone, rise more, in the people who win and then the losers wrestling matches. Things of that sort with a simple prediction and the answer wound up being you didn't see a simple answer. Okay, you win the marathon that's not necessarily an increase of predictor of increased testosterone. What's that about? And then you find like, you know, the winner testosterone decreases and you find out the guy who came in 70
The third is having a massive testosterone increase. Whoa. What's that about? What's that about is far more. Human subtlety. The first, the guy who won the race as a decline in testosterone because he came in three minutes later than he really really was expecting. And everybody now is going to be writing it up about how he's over the hill and the guy who came and 73rd is having a boost of testosterone, because he was assuming he'd be dead from a heart attack. When third mile, instead. He managed to finish.
It's this interpretive stuff going on in there. And that's what prefrontal cortex is about
amazing. It raises this question of cognitive flexibility, you know. Can can we tell ourselves that something is good for us? Even if we're not enjoying it and can we can we wriggle around these corners of choosing the exercise or doing the? You know, I personally am not a big fan of
Um, long, bouts of meditation, but I've benefited tremendously from things like, dedicated, breathing and shorter rounds of meditation. Can I tell myself that it's good for me and wriggle around the corner and get my physiology working? The way I want? Do we have cognitive flexibility. Can I be that third place Runner and tell myself? Well, at least I'm I came in I wanted to win so badly. That was my primary goal. But another goal was to beat my previous time and I did do that.
That. And so, I mean, it's what, to what extent can we toggle? This relationship between the prefrontal cortex and these other more primitive systems
and an enormous amount, you know, for example, being low and hierarchy is generally bad for health and like every mammal out there including us, but we do something special, which is we can be part of multiple hierarchies.
Same time. And while you may be low ranking and one of them you could be extremely high ranking in another, you're like, have the crappiest job in your corporation. Would you were the captain of the team, softball of the softball team this year for the company, and you better bet that somebody who's going to find all sorts of ways to decide that nine to five, Monday to Friday is just stupid paying the bills. And what really matters is the prestige and the weekend your poorer, but
You're the Deacon of your church, your. And so we can play all sorts of psychological games with that. One of the most, like consistent reliable ones that we do, and need to use the frontal cortex. Like crazy is, somebody does something rotten and you need to attribute it. And the answer is, they did something rotten because they're rotten, always have been always will be this constitutional explanation. You do something wrong to somebody and how do you explain it afterward?
A situational one. I was tired. I was stressed in this sort of setting, I misunderstood this. We're best at excusing ourselves from bad things because we have access to our inner lives and we've got prefrontal cortex. Has that are great at coming up with a situational explanation rather than, hey, maybe you're just like a selfish rotten human. You need to change and that's all prefrontal cortex, and we do that every time.
We don't let somebody, you know, merge in the lane in front of us. Even though you curse somebody who does the same thing to you and you know, endlessly,
your, I love it. Your statement about the fact that we can select multiple hierarchies to participate. In to me seems like a particularly important one nowadays with social media being so prevalent. I know you're not particularly active on social media, although you
Be pleasantly, or I don't know. Unpleasantly surprised to find out that there's a there's a lot of positive discussion about you and your work. So you don't even need to be on there. We'll just continue to discuss your work. But the but what's interesting about social media I found is that the context is a very, very broad. I mean, one could argue that who one selects to follow in, which news articles you're reading etcetera can create of kind of a funneling of information that itself can be dangerous, you know, more verification of crazy ideas or or even
Just less exposure to new ideas. But there's also this idea that social media is an incredibly broad context. So as you scroll through a feed, it's no longer like being in your eighth grade classroom or your office or your faculty meeting, you are being exposed to thousands. If not millions of context, this meal that soccer game, this person's body. This person's intellect. YouTube is another example. It's a, it's a
Vast vast landscape. And it's so the context is is completely mishmash. Whereas I'm assuming we evolved, think we did evolve under context, that were much more constrained. We interacted with a limited number of individuals and unlimited number of different domains Seasons tended to be constrain us all. And of course, then we got phones and televisions in the started to expand, but now more than ever our brain, our prefrontal cortex and our sense of where we exist in these multiple hierarchies.
He's has essentially wikked out into Infinity. How do you think this might be interacting with some of these more primitive systems and and other aspects of our of our
biology? Well, I think what you get is in some ways, the punchline of what's most human about humans, which is over and over, we use the exact same blueprint, the same hormones, the same kinase, is this,
Same receptors the same, everything were built out of the exact same stuff as all these other species out there and then we go and use it in a completely novel way. And usually, in terms of being able to abstract stuff over space and time and dramatic ways. So. Okay, you're a low-ranking baboon and you can feel badly because you just like killed a rabbit and you're about to eat and some high-ranking guy boots you often.
Takes it away from you and you feel crummy and it's stressful and you're unhappy. We are doing the exact same things with like our brain and bodies when we're losing a sense of self-esteem, but we can do it by watching a movie character on the screen and feeling inadequate. Compared to like how wonderful or attractive they are. We can do it by somebody driving past us and expensive car and we don't even see their face and you can
You belittled by your own socioeconomic status. You can watch like the Lifestyles of the Rich and Famous or read about what Beezus is up to. And for some reason, decide your life is less fulfilling because you didn't fly into space for 11 minutes. And so you could feel miserable about yourself and ways that no other organism can simply because we can have our meaningful social.
Works include like the party you're reading about on Facebook that you weren't invited to because it is taking place in Singapore and you don't know any of those people but nonetheless somehow that could be a means for you to feel less content with who you've turned out to be.
Do you take steps in your own life to actively restrict the contexts in which you think and live and, and contemplate in a, you know, in order to
Enhance your creative life. Your intellectual life. Are those are those steps that you actively take.
Well, I very actively, don't know how to make use of anything with social media. So I guess that counts as my having thus actively chosen not to learn hell. So that's the case. Shouldn't lie for the last year and a half, like lots of people, I've gone through stretches where I can manage to sort of enforce a moratorium on.
The news and I was wonderfully free. I think in the larger sense, though. In addition, to me, being a neurobiologist. I'd through spent decades spending part of each year, studying wild baboons out in a national park in East Africa. And I've spend three months a year without electricity, without phone calls with, you know, going 12 hours a day without saying a word to somebody. And when I finally would it would be
Somebody nomadic pastoralist guy in a different language. Yeah, I did 90 percent of my like insightful thinking about anything in the laboratory during those three months each year and not one in the lab and that would be inundated with stuff.
I think there's reverse shifting Trend towards trying to create a narrowing of context that people. And I like, what I see. I have a nice, she's 14 years old, and she, and her friends are very
Good at putting their phones away. They say we're not going to have our phones for this interaction, especially after and I realize we're still someone in this. It's unclear where we were headed. But app 2020 was so restrictive and she was so separated from her friends. Now, it's, let's really focus on being together and not bring in all these other elements from our phones. And I have that brings me great. Hope for the that generation. Maybe they will, you know, or who knows? Maybe they'll run off and study baboons. We need more.
Or field researchers. So along the lines of choice. I'd like to shift gears slightly and talk about Free Will about our ability to make choices
at all.
Well, my personal way out in left field, inflammatory stance is, I don't think we have a shredder Free Will despite.
You know, 95% of philosophers. And I think probably the majority of neuro scientists saying that we have free will and at least some circumstances. I don't think there's any at all and the reason for this is you do something you behave. You make a choice, whatever. And to understand why you did that weird that intention come from part of it was due to like
The sensory environment you were in the previous minute. Some of it is from the hormone levels in your blood stream that morning. Some of it is from whether you had a wonderful or stressful last three months in which would Enduro plasticity happen. Part of it is what hormone levels you were exposed to. As a fetus part of it is what culture? Your ancestors came up with and thus, how you were parented when you were a kid, all of those are in there and you can
Stand where behaviors coming from without incorporating all of those. And at that point.
Not only are there all of these relevant factors, but they're ultimately all one factor. If you're talking about what evolution has to do with your behavior by definition. You're also talking about genetics. If you're talking about what your jeans have to do with behavior by definition, you're talking about how your brain was constructed or what proteins are coded for. If you're talking about like your mood disorder, now,
You're talking about the sense of efficacy. You were getting as a five-year-old. They're all intertwined. And when you look at all those influences, basically, like the challenges show me a neuron that just cause that behavior or show me a network of neurons that just cause that behavior and show me that nothing about what they just did was influenced by anything from the century environment. One second to go to the
Lucien your species and there's no space in there to fit in a free-will concept that winds up being, you know, in your brain, but not of your brain, there's simply no wiggle room for it there,
so I can appreciate that. Our behaviors and our choices are the consequence of a long line of dominoes that fell prior to that behavior, but is it possible that I can
Dean in the domino effect, so to speak, you know, in other words, can my recognition of the fact that genes have heritability. There's an Epi genome that there's a hormonal context. There's a historical context, can the knowledge of that gives me some small small, Shard of Free Will meaning, does it allow me to say? Ah, OK. I accept that. My choices are
Somewhat predetermined and yet knowing that gives me some additional layer of control is, is there any philosophical or biological Universe in which that
works? Nah?
All of that can produce the wonderfully, positive belief that change can happen, even dramatic change, you know, we're some circumstances most unlikely people and change can happen. Things can change. Don't be fatalistic. Don't decide because we're mechanistic biological machines that nothing can change can happen. But where people go off the rails.
Is Translating that into we can change ourselves?
We don't, we can't because there's no free will. However, we can be changed by circumstance. And the point of it is like you look at an app leesia. A sea slug that has learned to retract. It's Gil and response to a shock on its tail. You can do like conditioning Pub, Logan conditioning on it and it is learned. Its Behavior has been changed by its environment.
And you hear news about something like horrific lie, depressing going on and you know refugees and in wherever and as a result you feel a little bit more helpless and less of a sense of efficacy in the world and both of your behaviors have been changed. Okay? Okay. Yeah, I guess that's but the remarkable thing is, it's the exact same.
Ecology, the signal transduction Pathways that were happening in that sea snail, incorporate the exact same kinase is and proteases, and phosphatases that we do when you're having mammalian fear conditioning, or when you're alert, it's conserved. It's the exact same thing. It's simply playing out and obviously a much, much fancier domain and because,
You have learned that change is possible, despite understanding mechanistically that, we can't change ourselves volitionally, but because you understand changes possible. You have just changed the ability of your brain to respond to optimistic stimuli and you have changed the ability of your brain to now send you in the direction of being exposed to more information that will seem cheerful rather than depressing.
My God, that's amazing what Nelson. Mandela and Martin Luther King and all these folks did. WOW under the most adverse of circumstances. They were able to maybe I can also maybe I can go read more about people like them to get. Even more data points of changed. Neurochemistry, so that your responses are different now and, you know, you're tilted a little bit more in that direction of feeling like you can make a
Difference instead of this all damn hopeless. So enormous change can happen with the last thing that could come out of a view of, we are nothing more or less than the sum of our biology. And it's interactions with environment is to throw up your hands and say and thus, it's no use trying to change
anything.
So we can acknowledge that changes extremely hard to Impossible, that circumstances can change and yet that striving to be better. Human beings is still a worthwhile Endeavor. Do I have that?
Correct? Absolutely, because simply the knowledge either from experience or making it to the end of the right neurobiology class as talk you that change can happen within a framework of a mechanistic neurobiology.
You were now more open to being made optimistic by the good news in the world around you you are more likely to be inspired by this or that you were more resistant to getting discouraged by bad news, simply because you now, understand it's
possible.
Yes, somebody who spent much of his career working on the hippocampus. I have to assume that you are a believer in neural, plasticity, that neural circuits can change in response to experience. And that some of the same so-called top-down mechanisms of prefrontal Cortex that we were talking about before can play a role there that the decision to try and change and the pursuit of knowledge and the pursuit of experience can shape our circuitry and therefore make us different machines. So to speak.
Yeah, and not only can
Say prenatal hormone exposure change the way your brain is being constructed. But learning that prenatal hormones, exposure can change the construction of your brain, will change your brain right now. And how you think about where your intentions came from. Wow, maybe that had something to do with it. The knowledge of the knowledge is an effect or in and of itself.
That's such an important and Powerful statement to hear. I think that many people think that if a tool it is doesn't involve a pill or a or a protocol that it's useless and certainly there are pills and protocols that are very useful in a variety of contexts for a variety of things. But the idea that knowledge itself, whereas you put it knowledge of knowledge is itself. A tool, I think is a very important concept for people.
Embed in their minds. And listen, I'm so grateful for this discussion and for you, raising these topics. I think that people, you know, many people know your work on testosterone on stress, and we've covered some of that today. The work on Free Will. And this idea that we are hopeless or that, we are in total control. I think I'm realizing and listening to you that it's neither, neither is true. And that the solution
Resides in understanding more about Free Will and lack of it and and also neural plasticity. You're working on a book about Free. Will. Are you willing to tell us a little bit about that book and where you are in that process and what we can look forward to?
Yeah. It's going really. Slow title is determined a science of life without Free Will. And essentially the first
After the book is trying to convince the reader. Okay. If not that there's no free role whatsoever. But at least there's a lot less than is normally assumed and going through all the standard Arguments for free will. And why that doesn't make sense with 21st century science, and that has led to Leading reading a lot of very frustrating philosophers who basically are willing to admit.
Mitt that stuff is made out of like atoms and molecules and like there's a physical reality to the world. They're not just relying on Magic but that they believe in Free Will for Magical reasons, and we're doesn't make sense. Okay. So the first half of the book is to hopefully convince people that there's much. Less Free Will needs to think, and then the second half, is this gigantic juncture built around the fact that I haven't thought there's any free will since I was like an ass.
Lessened. And despite thinking that way, I still have absolutely no idea how you're supposed to function with that belief. How are you supposed to, like, go about everyday life? If anything you feel entitled to isn't true? If any angers and hatreds, you feel aren't Justified if there's no such thing as appropriate, you know, blame or punishment, or praise, or reward, and none of it makes any sense and somebody
Like even compliments you on your haircut and you've been conditioned to like say oh well, thanks as if you have something to do, how are we supposed to function with that? And so the second half is wrestling with that and what the punch line there is, is it's going to be incredibly hard and if you think it's going to be hard to subtract a notion of Free Will out of making sense.
Serve like serial murderers. It's going to be a thousand times harder of making sense of when somebody says good job to you. And because it's the exact same.
Unreality of sort of our interpretations. It's going to be incredibly hard. But nonetheless, when you look at the history of how we have subtracted, the notion of agency out of all, sorts of Realms of blame starting with thinking that which has caused hailstorms 500 years ago to the notion that psycho dynamically screwed up Mother's cause schizophrenia.
We've done it, we've done it. Endless number of times. We've been able to subtract out a sense of elation and understanding how the world Works around us. And we don't have murderers running amok on the street and Society hasn't collapsed into a puddle. And in fact, it's a more Humane Society. So the good news is, it's possible because we've done it repeatedly in the past, but it's going to be hard as hell. And
It's hard as hell. To try to write about that coherently. I'm discover. And so, it's going slowly.
Well, I speak for many, many people. When I say that, we're really excited for the book when it's done, and we will patiently, wait, but with great excitement for the book, determined you said it's the title, correct? Yeah,
determine the science of life, without Free Will seems like you can't publish your book these days without a subtitle. So,
That's that's it.
Fantastic. Well, very excited to read the book. Very grateful to you for this conversation today. I learned a ton every time you speak I learn and for me, it's really been a pleasure and a delight to interact with you today and over the previous years. I should say as colleagues and thank you, again, Robert for everything that you do, and all the hard hard work and thinking that you put into your work because it's clear that you put a lot of hard work and thinking,
And we all benefit as a
consequence. Thanks, and thanks for having me. This was a
blast.
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