Stress with Jen Byrd-Craven
2026-03-17 12:00:00.000 +00:00

David, this is Evolutionary Psychology the Podcast. You're David Pinsoff. I'm your Dave Petrozuski. This is Evolution, this is Evolutionary Psychology the Podcast, Actual Evolutionary Psychology by Actual Evolutionary Psychologists. Uh today we have Jen Bird Craven. She is uh at the intersection scientifically of the mind and the endocrine system, and that is uh what we talked about today. Yeah, we talked all about the nuances of stress and cortisol and what it does to the mind and body and the evolutionary origins of stress, its functions. Um, this was a big learning experience for me. I feel like I learned a lot about how stress works, how the endocrine system works. Yeah. Why do we need an endocrine system?

Why do we need a brain? Why do we have stress? Why is it bad? Why does it feel bad? Is it all bad? Uh all these things. And yeah, I I certainly learned a lot too. I feel like this is some of these episodes we are experts, and some I feel like we're we're bumbling uh idiots. And I actually really enjoy the latter category because I learn a lot and I feel like this was that latter category for me at least. Totally. Yeah, it was great to just expand my knowledge on a hugely important topic, which is stress. So if you feel stressed or not at all, um uh and if you have uh opinions about stress or know somebody who is stressed or wants to be less stressed, or does anybody want to be more stressed? Uh maybe maybe some people.

They're just too chill and they gotta figure out. Actually, I wanted to ask I wanted to ask Jen. Jen, if you're listening, I forgot to wanted to ask you, is there anybody who doesn't have stress? Like like there's people who are born without pain. I wonder if there's people who are born without stress, and I wonder what that does. Yeah, that would be fascinating to look at. Yeah, I've no idea. Well we can circle back to that. Maybe we can have Jen back on and we're work we can get somebody in the comments saying, I don't have stress, and here's what my life is like. Yeah. Well, kick back, relax, um, avoid activating your stress response and enjoy this episode with Jet Bird Craven. Is as I understand it, you study not only psychology, but something called the

endocrine system. I do. Um, we really haven't had uh an endocrine person on. We've we've sort of touched on it very lightly, but what is that and why do we have it instead of just a brain? Right. Um, that's a great question, actually. Um, so the endocrine system is is super old. Um, we share it with, you know, um almost all other um vertebrates um and things like that. And um it, you know, it essentially works alongside neurotransmitters and things like that to motivate our behavior. Um, and so I'm interested in, you know, sort of what motivates us and how can we sort of assess that. Um, and the endocrine system is a beautiful system to be able to tell us what organisms are prioritizing in the moment.

Um, and it's also a ton easier to measure than um brain activity um and things like that. So do you feel like people who study the mind from a computational perspective overlook the motivation and embodiment element? Because I've noticed as we sort of have technology and computing technology, it really emphasizes the information processing part of the picture. But then it all almost makes everything else feel like magic. Right. Is that have you noticed this at all or felt come up against this? I have a little bit, particularly in like in reviews um and things like that. Um when we send things to more general journals, um, it's you know it come it comes up and uh and also just even in teaching and things like that too with other, you know, students

um and that sort of thing. So um and it is really, you know, sort of, you know, people don't uh in my opinion, I'm biased, um, but they don't pay enough attention to these, you know, sort of older systems that are informing these newer information processing systems. So we're taking a brain-centric perspective, and really the endocrine system got there first in a way. Maybe as a way of putting it. Okay. Right. Yeah. Absolutely. That's interesting. I mean, I have a a a a deeper question. It's okay if you don't know the the answer to it, but it seems like a brain naively would be enough. Like if you need to motivate behavior, you have neurons, they're connected to our muscles, they're connected to our hearts, they're connected to our lungs.

Um, they can send a message to say, Hey, get going. Uh, you know, make the heart go faster, make the muscles tense up, get out of that situation. Seems like the brain is enough. Why do why do you need this whole complicated endocrine system. Yeah, that's a that's a great question actually. And you know, it's important to remember that a lot of this starts in the brain. And so like, you know, the hypothalamus, pituitary glands, and things like that, you know, we tend to think of like puberty is a great example. We tend to think of puberty on the level of the gonads, right? That's not what's happening. It's the pituitary that's signaling down to the gonads to start producing, you know, their stuff.

And so I think that you know having it integrated with the limbic system and uh things like that allows you to, you know, sort of be more flexible in your behavior, perhaps. Um, but it's also you remember brains are expensive, right? Um, and so if we could sort of, you know, have this on a you know, sort of um more simple level, um then that might, you know, sort of solve the problem without having to recruit um the brain. It's really when we, you know, sort of run up against challenges that we can't, you know, sort of just operate on the autonomic nervous system anyway that we then start recruiting higher, higher processes. Can I ask too, like, you know, if I think about from the perspective of development,

development is a chemical soup process where genes are contingently orchestrating the building of stuff. Um, is is it that, you know, the the brain is sort of neurochemical and can change the structure? So, like, you know, if electricity is in the right place at the right time, that can cause chemical changes and structural changes. But is the idea that the endocrine system is sort of like analogous to development, that it can do a better job of continuing development, right? Like, I mean, I think people I have a I even I have a cartoonish view of development as like, you know, once you're uh a certain once you're sort of an adult, you're done developing, but that's not an adaptationist way to think about the contingent

building of the phenotype. Is is that is that also true that the endocrine system is sort of this ontagenetic developmental chemical building process? Is that a a metaphor that's appropriate or not? Yeah, I think so. And you know, it stimulates gene expression or not, can silence genes and that sort of thing. And so even, you know, prenatally, one of the system that I'm most familiar with and I work with the most is the HBA axis, right? And so that can actually, you know, modify based on mother's stress levels, can modify fetuses, um, you know, gene expression in a number of different areas, um, metabolism, um, you know, um, just you know, essential stress response um and things like that. And then that process just sort of continues across development.

Um, obviously, you know, with puberty being sort of this massive reorganization and you know, sort of sensitive period of that, then you have, you know, um a lot of these um endocrine systems sort of recruiting higher level processes um to be able to is coordinate behavior and you know adapt. Yeah. Stress sounds really interesting and I'm sure we're going to get into that. I have another dumb question, um, which maybe again like to with David's caveat of like if if if we don't, if this is a a too big question, but why do we have puberty? Like why, why don't we just build um The adults. Why do we have extended childhood? Yeah, that's a great question. You know, and humans are unique in that we have a period of childhood that the other

apes don't have. They just go from infancy to juvenile period to adulthood adulthood. And then you also have, you know, adolescence is unique among humans, and particularly, you know, that growth period and things like that. And so I think that, you know, just drawing from like Barry Boggan's work um and some other things, childhood essentially is a feeding adaptation, right? Um and to be able to, you know, sort of um free mother up from lactation um and things like that, that frees her up to produce other offspring. And then you sort of outsource um that, you know, care of that little, you know, immature to, you know, um fathers, grandparents, aunts and uncles, others in their community, and

that sort of thing. And during that time, they're learning about the social environment. And humans are, as you guys know, just incredibly complex. And our culture and you know, even social groups change so quickly from generation to generation that you can't really have a system that's very static. And, you know, from the beginning, you need to have a system that's plastic and able to sort of modify these neural neural systems according to the appropriate context. So is it is it that building sort of a complete sexually mature adult right at childhood would be too costly in terms of energy? And that if you're a baby, you want to be as uh as you don't want to be too demanding of your uh parents' time and energy.

And if you had complicated sexual equipment to maintain, that would just be an extra drain on your family. And you want to try to be as cost effective as possible in this early period and save that energy intensive sexual maturation for later when you have uh perhaps accumulated more embodied capital and you are able to make those expenditures. Is that right basically the idea? Yeah, that's essentially the idea. And then it also allows for learning. It allows for, you know, sort of fine-tuning these systems to the particular cultural context, not only learning about technology, but learning about people, how they work, you know, who's aligned with who. You know, kids start tracking status and things like that.

And there's some evidence to suggest that that is better, you know, sort of fine tuned under the protective umbrella of parents and others, um, versus you know sort of getting right to it. You might get it wrong. And particularly because you know our groups are are so incredibly complex socially. And from a biological perspective, the idea of a morph, which is like a subtype or a version of a body, I guess is sort of the broadest way. So I guess the idea is that we have age morphs and is it that we're Are there, I mean, I mean obviously there's like you know developmental morphs where there's like a butterfly and a chrysalis and a caterpillar before the butterfly. Um, are our age morphs weird um compared to other species?

They are, they're very weird. Um, and that we, you know, we have a new a number of unique life history factors. So, you know, I mentioned childhood and adolescence. We also have menopause. So we have you know women living two, three decades longer, um, you know, past their um reproductive um periods. What is what is that about? You know, um, what is that for? And if you understand childhood in in a unique way, you can understand menopause uh to some extent. So mother grandmothers that are, you know, sort of helping to provision and also helping to teach um, you know, these complex social um systems, um, again, sort of you know, frees mom up to reproduce again. So, you know, overall reproductive success is higher and that sort of thing.

But it um it is, you know, it's it's a beautifully designed system in in a lot of ways, but also suggests that our evolutionary history was really strong with social selection. And you know, those that were, you know, a little bit more savvy and social skills did a lot a lot better. Yeah. I what I'm hearing you say, and just to make explicit, maybe for listeners, is that there's been arguments that we are foraging niches extractive, which is like we make a living. We're not like koala bears where you just eat a eucalyptus trees, leaves, whatever. We we we are we extract really difficult high process things like the process demand things, like and uh and then also socially we're very uh arms racy to put it simply.

Um, and so both things sort of are an arms race of ever increasing complexity. So, in some sense, we have a really hard job, and so it requires a lot of help, a lot of learning. Yeah, I think that is that a fair sort of summary, or at least like that's the one that's sort of why we're complicated, right? Like there's it, it's we're very biased to think intelligence is a good thing, but in some sense, from a biological perspective, it's very costly because of time and energy. And it's really we we we are we're sort of an unfortunate possibility space in organism space from a Dawkins perspective, in the sense of we have to be complicated because of the way we make a living, I guess. Right, right.

Absolutely. Yeah. And you know, they're just things that don't translate very well in a canalized form from generation to generation. You know, um, you know, foraging, you mentioned, is a is a great example of that. Um, we forage in a lot of different niches. Um, and you know, eating the wrong thing could kill you. Um you have to learn how to process, you know, um different kinds of foods and um things like that, and all that is you know um happening through this developmental process. Right. So you can't build into the germline the information about how to make a living. So it's setting up these more open parameter systems, yeah. Yes, absolutely. And you certainly can't build in, you know, sort of, you know, mating systems and, you

know, peer networks and, you know, all of those sorts of cultural things. Yeah. Is is a a a fruitful way of thinking about this in terms of the economics of energy uh and the endo endocrine system is you can think of them as kind of economic planners of, you know, uh channeling energy toward particular activities at particular life stages. So when you're in childhood, the best thing you want to do is invest energy in just eating and learning. Like that's that's your job. And then uh once you've eaten enough and learned enough, it's time to start competing for mates. And that and then you want to channel all the energy into sexually developing and competing for mates and entering you know so status games, whatever.

Uh and then you know, once you get older, you have kids, um, you want to channel energy into investing in those kids. Uh for women, if you start to have grandkids, you might want to uh uh channel effort away from mating competition and into investing in the grandkids. Uh and behind each of these shifts in energy uh throughout the lifespan um are the uh the the endocrine mechanisms that uh uh that channel uh energy allocation in different directions. Is that uh a fair way of of describing the the evolutionary logic of it? Yes, absolutely. That's perfect. Um and the endocrine system really gives us an idea of how that energy is being distributed and and to what extent, you know, in in different domains.

Um so that's why I love it is is that it really gives you an idea of what you know what is motivating that organism in that, you know, particular moment in time. Yeah. And I remember when I was a kid, uh I think it was like elementary school, there was like a poster. I have like a very vivid memory of it where I talked about the different stages of life. And I don't know, I don't know what source this was, but it was it was something like the equivalent of like, you know, it was like childhood play, like parenting, be productive. And I remember thinking, how do people know that? Like, I think my my implicit like kid model was sort of like I was maybe I was being blank slatey about it, but I was sort of like, How is it possible?

I didn't have the vocabulary to say what I'm gonna say now, but what my question was was how is it possible that this the human uh lifespan is reliably developing enough that people can predict people's motivations at different times in their life? Um, and I think that that's I I imagine scientifically in the history of the sciences that that is a phenomenon to be explained. And I wonder, you know, I and and maybe this is a getting the segue into how you got into this. But I can imagine one way to approach or how to get into the endocrine system or an evolutionary approach to the endocrine system is to look at phenomena like reliably occurring different phases of life and start to ask well, why would that exist?

Right. And another way is to sort of say, given an adaptive problem, what might not we be looking for? Or what might be missing? And you can kind of do both. How did you get interested in doing an endocrine informed psychology and marrying those two from an evolution perspective. And maybe this is relevant to the answer, but I'm also curious, sort of in that continuum of phenomenon first versus adaptive problem first, is is that is, you know, along that continuum, how is that informing that broader story of how you got interested in the endocrine system? Yeah. Yeah, that's a great question. So I really, you know, came through through this through through development. Not, you know, a lot of people, you know, sort of come at this through the mating context,

right? Um, and they get into interested in that. And um I think, you know, one of the things that I was really fascinated with as an even undergraduate student is the fact that that, you know, like you just mentioned, there is such universals in human development. Um, language is a is a perfect example of that. So we're exposed to different languages. Obviously, that the output is different. But if you look at kids across the world, they are reliably, you know, their first word comes about, you know, one year old. And you know, all of these things are very reliably sort of patterned. And then discovered that, you know, this marker of, you know, sort of where you're motivated happens to be, you know, really found in the endocrine system.

That you can, it's a, you know, sort of different than like heart rate and and and things like that it's a much more sort of um broad measure of um sort of where is this individual attending um and uh that sort of thing so one of the the um things that you know and I could sort of explain um so you know some of the work that I've done in in my lab but also um related to you know drawing from from other folks um so Laura Stroud is a researcher that does just, you know, sort of biopsy um type stuff and doesn't really come at it from this, you know, sort of more evolutionarily informed perspective. Um, but um, one of the findings that um I was fascinated with early is there's sex differences in um, you know, particularly, you know, we're we all get stressed over a lot

of the same things, but there's some things that men are more much more likely to at least show a stress response on if you ask them, it's essentially the same, but they show a stress response and then uh it's different for women. Um, and what's interesting about this is that doesn't show up, that different doesn't show up until puberty. So when you do, you know, kids on the in these paradigms, um, you don't see any sex differences, all of a sudden puberty comes in line, and you start seeing um these different responses in the stress response system, not in the in in um, you know, testosterone or estrogen and you know things like that. So they're tending to different um different aspects of their social

environment. And, you know, a lot of these things are, you know, a lot of times people say, well, isn't that socialized, right? But it's, you know, we see it pretty reliably developing across different cultures and, you know, um, you know, replicated across time. So for example, men are more likely to show a stress response and boys, adolescent boys, over you know, these public achievement stressors, right? Anything that can, you know, sort of impact your status publicly, a public performance, you don't do well, that's that's going to initiate a really um really nice stress response. Women also show that, um, and and adolescent girls, um, but not to the extent that men do. Women are much more reactive to social rejection, um even very, very subtle forms of social

rejection. And so um you could, you know, get people in a lab um and you have two confederates and they start talking to each other more so than the actual participant. So even that, they're not being rude, they're not, you know, physically rejecting her and things like that, just this beautiful nice stress response to that. Um people do not like it. The men in the situation, again, you know, will show some stress response, but not not to the extent. Um and those things are adaptively patterned. If you think about it right around you know adolescence, what you should be attending to, what men should be attending to is their public status, their explicit these status competitions and things like that.

That should motivate their behavior to attend to these things, you know, sort of um be able to fix things, fix mistakes and those sorts of things. And the same thing for women. So social rejection has really big consequences starting in adolescence and then in adulthood. And so you should be attending to those things. And again, this motivates you to repair to some extent. Just to push on the social rejection versus public representation. has there been work sort of unpacking what exactly is the representation? Like I don't maybe, maybe not. I mean, because I I can think about it sort of as it's all status in at a at a sort of more abstract level. And and I think too, you mentioned that you know it's the socialization.

There's been like a history of sort of there's been lazy evolutionizing and anti-evolutionizing in the past where it's sort of like, well, here's a behavior, is it learned or innate? Right. And I think the the the we're all doing the more complicated second wave thing of sort of there's some evolved representations, and there might be sex differences or even not about certain things being more problematic or putting more motivation behind, or this is sort of the north star of the control system, you know? And so I'm just wondering like they sound both like status. And I actually can't even uh tell apart maybe maybe it's sort of like a common knowledge versus I like I don't actually can't even reverse engineer exactly

what's different between like I intuitively I get public uh status versus social rejection. But I can't actually I couldn't tell you a rope what the robotic software level difference between those two things are. Yeah. Right. Yeah. And you actually bring up a really great point is that they are both status. It's just, you know, sort of, you know, how we in psychology are used to measuring status um versus not. So we're not really, you know, used to having this more evolutionarily informed um aspect of like, you know, status for women is you know sort of this social acceptance and and sort of you know how you're valued in the group same thing for men it just is expressed it you know quite differently and so um these stressors that I was talking about are more like

achievement stressors so as an example um you know participant comes in and they're asked to solve an unsolvable math problem um or memorize um a you know difficult passage like Paradise Lost or something like that and then repeat it um to the experimenter and then they see a confederate do quite well Um, so they're outperformed, um, essentially. And um, I think, you know, particularly for like skills, you know, you want to demonstrate that you're a skilled um member of your coalition, a valued potentially valued member of your coalition. Um, and and what that does is that just very publicly says, No, you're not. Uh so um I I I that's a great point. And that they're really both status. I see.

Um it's just how it's expressed. And also, I guess it would be an opportunity for like aggression. because I also think like sometimes male aggression is sort of oafish in in public, right? Or it's sort of like, oh, you're stupid, right? Like and and yeah. So um it's interesting, but it's interesting, yeah. Like the burden would be to sort of um unpack exactly what the representation is. I'm guessing we're gonna bump up against that a lot because I imagine, because I would also like to ask about stress, is a lot of the constructs you've inherited and we've all inherited are not coming from an adaptationist or even selection pressure or adaptive problem first. And I and there's often sort of a uh instinct blindness or essentialism

about it where it's intuitive, but that's a problem because then we don't really unpack what it is. Um so yeah, I mean is that true? You're saying yes. Is that absolutely yeah? Um and you know that much more so, obviously, in in sort of mainstream psychology than you know, um in our field. We we think a little bit differently about things. But um yeah, that's that's one thing that I come across a lot. Okay. I mean, maybe then this is a lead into then what is stress or is it even a thing? Um and it it's an intuitive and obvious and we all experience it. But then yes, can you disabuse us of the instinct blindness of stress? Yeah, absolutely. Well, and you bring a good a good point in that um oftentimes we're really poor reporters

of our own stress. Um, so um there's a lot of you know things that are happening sort of under underneath um underneath the hood, so to speak, um, that we're not aware of. Um, and um adolescents in particular are really horrible. Um, reporters of of you know, sort of, you know, how stressed you feel, rated on one to ten, you know, um, that sort of thing. So uh and in terms of being bad at reporting this, is are you are you talking to about a disconnect between self reports of how stressed a person is versus a physiological response? Yes. Such that a person might say that they're not very stressed, but physiologically they're revealing uh indicators of stress. Is that what you're talking about?

Yeah, that's what I'm talking about. More more commonly, it's the other way around. Um, so those like I'm very stressed, and and then you don't really see any physiological indicator of that. So interesting. Um yeah, yeah. But I I to answer your question of what is stress, you know, you can go way back to, you know, Hansele and, you know, things like that. And and, you know, essentially, you know, when the demands exceed the resources, you're going to experience, you know, sort of a disruption in homeostasis and you know, um, that sort of thing. So that basic definition is actually um really useful to build on, you know. Um obviously humans are much more complex than that, um, but um that's that's sort of you

know the foundation um that I that I you go from. Um and it's also important to, you know, sort of differentiate the two different stress responses. So the autonomic nervous system versus the HPA axis. Um, so autonomic nervous system more into the, you know, sort of current stress, acute stress. Um, the HBA axis is more recruited when that doesn't work. Um, so um, you know, you're experiencing a stressor and whatever you're doing, um, maybe what you did last time isn't working this time. And so then you recruit the sort of more expensive system um that's going to produce cortisol that um can, you know, is associated with sort of reorganizing um neural networks. And so to some extent, I really don't like the word stress um because a lot of times what

we're measuring is more like arousal, um, attention, focus, you know, um, those sorts of things, not necessarily, you know, sort of the what lay people um perceive as stress. Could could you have in theory a a positively valenced stress? Absolutely such that maybe maybe you found a really great mate and you're really excited and you can't stop thinking about the person uh and uh and it just fills you with energy. Would that be a kind of stress and would it show up physiologically as a stress response? It does. Um it sure does. Um so yeah the those people that are in the early stages of a romantic love when they're uh interacting with their partner, they they um show pretty nice stress response.

Um also kids, um, for example, like you know, the day before Christmas, um, right, um, they might be, you know, and pr there's you know uh anticipating um this great event um and that sort of thing a lot of times they'll they'll um show pretty high cortisol levels but they're happy. You know the affect is is excitement and um that sort of thing. That's fascinating. I mean, it suggests one way in which our intuitive notion, our full concept of stress is wrong in many ways, that it doesn't necessarily always need to be negative. What it is is basically the body mobilizing energy to deal with something. And it could be mobilizing energy to deal with a bad thing or a good thing. Right. Um that's that's really interesting.

It's kind of magical. I mean, in a way that it's obvious when you because we experience it, but it's sort of a system that's saying, like it's predicting based on informational cues in many cases, it's it's detecting a situation, and then it's creating in planning for future responses, um, and somehow knows what is more likely to be needed in the future. That's just sort of a magical thing, right? Yeah, yeah, it is. And it's, you know, sort of again happening all, you know, on the level of the brain to some extent. But yeah, and it's it's interesting in a way that we, yeah, uh the HPA access and cortisol in particular, the function of it is not necessarily, I mean, it does definitely mobilize, you know, resources and energy and things like that.

it's also associated with destabilization of neural networks, um, particularly if you're under chronic stress. Um, and that, you know, a lot of times in in, you know, sort of mainstream psychology, they say, oh no, the stress, you know, the stress response system is dysregulated. We need to fix this. It's actually an adaptive process because what what the the cues that are coming in is what you're doing isn't working. Change. You know, find some different neural networks, find some different ways of approaching um the situation. Yeah. I think one of the themes of this podcast has been respecting phenomena. And this sounds very much like a uh to almost channel David here, like stress is bad, right?

Like uh it's a bad it's bad stuff. We don't want bad stuff. And so anything associated with stress, we so deregulation, it sounds bad, right? It sounds like a tangle or something. But I is there, yeah, it sounds like what you're what I'm what I'm hearing you saying is that we should appreciate not only is it sort of not just in too many negatives, not only is it um maybe not just entropic, it might be smart. And we should at least respect and better understand what's going on first before we sort of in a patronizing way sort of say, well let's let's make sure we never get to stress, we never get to deregulation. Right. Right. Absolutely. So what is going on? Yeah. Uh or or maybe I mean maybe that's too broad of a thing.

I mean I it seems like a lot of your work has been looking at very particular things, which is probably how the systems work. There's no general stress response. Um can you give us maybe an example or um uh and maybe that's part of the story is that maybe you're arguing with people who think stress is general. I don't know. Like yeah, can you yeah? Yeah. Um well I guess you know, most familiar to me is I I've done a lot of work um with uh female friends and um a a paradigm that is um trying to mimic sort of a naturalistic um you know sort of playoff that that happens a a lot with, you know, sort of um and particular this is to some extent um you know um limited to age, but not not exactly. So um with um what I've focused on in the lab is um processes related to co-rumination, for

example. Um So you have friends that are coming together and they're discussing a problem that's outside of the dyad, but that is important to at least one member of the dyad. What is most interesting to me is that the friend whose problem it is not hers will also mount a stress response. And it's actually pretty consistent with her friends. And so what that tells me is what's going on there is part of it is not necessarily only to deal with our own, you know, sort of um scenarios, our own challenges and things like that. It's um to some extent to sort of, you know, uh prioritize another's um priorities, um, if that makes sense. And that what what does that do then? That helps bond you to that other person, you become, you know, sort of um, you know,

loyalty increases, the relationship quality increases, even while the stress response is is is doing its thing. Um, and so um I you know, I think to some extent we can, you know, sort of look at it that way. Um, and the it it was sort of surprising to some people that that you know both friends mounted a stress response on this. But if you think about it, what you're doing is coordinating and you're, you know, um also this is informative to you, right? Um sort of helping your friends solve their particular problem, maybe you can, you know, um be faster, more effective um at solving that social problem in the future. Yeah, it's interesting because it reminds me too of again, this is sort of instinct

blindness where you can imagine a simple model is you only have a real physiological reaction to things that involve you. But then of course, like, you know, like September 11th, like people have huge courtesy, you know, like super stress response. There's all kinds of, we know in popular culture, there's sort of like this is a disturbing video. Don't watch it if you do, you know. Like we, we, we are just swimming in emotional reactions. And arguably all most of our emotional reactions are third-party uh observations, right? Um, fortunately, probably. Um, so yeah, that's a really nice point to just sort of uh disabuse the the cartoonish view that sort of the the physiological stuff is really just for first person you know right

yeah absolutely that's why we enjoy movies right that's why we enjoy you know sort of reading stories and things like that as you're vicariously you know sort of going through this um with this character without taking the risk yourself. So there's a stress response in response to this friend who so what what can you yeah so can you kind of continue what do you think is going on with that stress response what's that for even in that particular situation yeah um I think you know if you think about it the the other way so um for example you're talking with your friend and um your friend is just you know sort of apathetic and they're just you know looking away they're not really you know sort of engaged um that's not a good ally right?

Um, that's not a good coalition partner. Um, and you know, um that sort of thing. So by showing that you're sort of, you know, you're engaged in this process, um, you're, you know, sort of um trying to unpack this with them, um, you know, maybe speculate um about the causes and consequences of this, you know, um system um and things like that, that um at least, you know, from some of the uh measures that we have, it's associated with them feeling closer afterwards. So they feel it it may be, you know, in part a sort of bonding situation. And um, I mean, you know, and we've all experienced that before. Like if we all experience the same stressor, right? Um, everybody feels a bit closer together.

I was just talking to my graduate students about that. They're going through their quant sequence together and they feel very, you know, very bonded now that they're all nice and stressed and had to do their mentor and uh those sorts of things. And so you feel, you know, it's it's almost like um, you know, fitness interdependence um in a lot of ways. You're sort of you know showcasing that. So yeah, go ahead. It's it seems like w what what you're saying is I I buy this logic of fitness interdependence that if if our fates are intertwined, then what's bad for you is is bad for me and what's good for you is is good for me. I mean the simplest example of that would just be with kinship or you know, what's good for

my daughter is good for me. When my daughter's happy, I'm I'm happy. But the same is true um with close friends, with close allies, there's interdependence there. But also, it seems like what you're saying is that part of the stress response may be a kind of costly signaling of interdependence. That if you tell me about your problems and I don't have a stress response and I'm blase about it and don't really react, I don't really pay attention, I look bored, I shrug it off, that's going to be a really bad sign. But if I uh am just as amped up as you are about the thing that you're dealing with and I'm just disturbed by it and appear to be having a stress response, then that is a costly and honest signal that I feel as if we are interdependent and that our faiths are

intertwined. And in in this sense, the cost would be paid in terms of the energy I'm burning to have this stress response. Um is is that an accurate way of describing how you're thinking about it? Yes, absolutely. Yeah. And so it's a yeah, it's a it's a signal that, hey, I'm invested in you. Um, I am your ally. Um, and uh and and that's that's really important, particularly, you know, in some relationships. If stress is important, why do we feel like stress is bad? Why is it unpleasant to be I mean, I mean, as David pointed out, maybe the uh there's a version of stress that is, you know, like, oh, I'm madly in love, and I'm around, you know. I mean, I think maybe maybe arousal uh is the folk category, right?

To um so maybe arousal is stress from a scientific perspective. But anyway, like why do we have at least half of arousal is quite negative and we call that stress? Why do we experience it as negative if it's so helpful from a functional perspective? Well, you know, I think if you think about like the emotion of fear, for example, like we don't like fear, we don't want to do, you know, um, we don't want to be afraid. Um, but it's really important that we have the capacity to do that, right? Um, and it's really important that, you know, and to some extent, you know, you can look at things like, you know, why do we watch horror movies? Um, why do we want to make ourselves we are deliberately scaring ourselves?

Um, what is What is that about? And I I think, you know, and there's individual differences and tolerance for that and you know that sort of thing. But I think, you know, what that's showing is just it's a motivational system, you know. Um, and um when we are experiencing the more negatively valent stress, um, that motivates us to, you know, sort of terminate whatever is causing it, um, or move away from it, or you know, um, that sort of thing. But it's it's quite informative. Is it is is what you're saying that the design itself of the system that's detecting the current state of the system or the organism is not sufficient to deal with the challenge. That this detection of the discrepancy creates a um

the motivation to change that into is is that it it tags that the current state is all of a sudden unpleasant, right? And that's part of the manifestation of all the engaged systems that are moving towards changing, if that makes sense. I mean, it's very abstract. I'm I don't know. Yeah, no, no, absolutely. But yeah, it's you know, it's adaptively calibrating your behavior to the context. Do people put them like I feel like this is there's also a mismatch thing where if you can avoid stressful situations, It seems like we would be designed to do so, but in an evolutionary environment, the range of sort of stressful situations we can avoid is maybe less, or maybe we have more control now to avoid stressful situations.

Like I'm thinking, a good example of this is there's good research on anxiety or stress and kids' play, where if you have kids that are avoiding anxiety-inducing play or stressful situations like difficult things physically or socially, it can actually backfire and stunt development. Yes. Obviously there's a middle Goldilocks thing, like you don't want kids to be, you know, going through barbed wire or um being bullied to the point of you know abuse or something. But but you don't want to cover kids in pillows and just have them re see smiley faces and happy stories all the time either. Um so I wonder, is there a mismatch in terms of our the controllability of avoiding stress? Maybe even for adults that may be unhealthy.

I don't know. Yeah. Yeah, no, absolutely it is. And I think, you know, uh adults try to do that for their children, right? Um, and and you know, you're right, it does cause problems. And so, you know, from developmental perspective, you want moderate stressors. Um, and you want to experience some stressors that are initially uncontrollable, um, that then move to the more controllable category. That's really the point, right? Is with coping skills and and things like that is this I can't control, but now I can control my reaction to it. I know what how to how to handle it. And um kids that don't have those experiences grow up to um have overactive stress response systems because it wasn't sort of inoculated during development.

Um and so then they just, you know, the they are hyper reactive um to literally everything. Um so parents can, you know, if they bubble wrap their children, um, they're actually harming them by doing that. And we're starting to see that more and more because of, like you said, our ability to be able to protect and to, you know, sort of control our environments. What we're seeing is that kids are not able to really deal with some of these challenges that they're experiencing or just, you know, just normal, typical, not like you were talking about like bullying and things like that, but just normal, typical, like, you know, how do I respond to that comment from my friend? Um, you know, um without getting, you know, sort of upset and looking in the truer and, you

know, um that sort of thing. Right. So sort of this is interesting because it it it gets into things like autonomy and feelings of re efficacy and responsibility. And the system sort of learns number one, I've learned how to deal with it in this k situation. Maybe the situation in an abstracted form uh will um uh will occur again. And then there's the meta thing of oh, I was stressed, I felt like I couldn't solve a problem. Um, but then I I was able to figure it out. Right, or there's a so it it it I'm just sort of fleshing out what you've already said that you sort of inoculate or learn that you can handle situations, yeah. Right. I mean we we talked about this a bit in the episode with um Colton Scribble Curiosity

and how we sort of learn how to self-regulate the more we expose ourselves. Um and the and the way I was tr trying to understand it was um there is uh a challenge in terms of burning the right amount of energy to deal with the challenge that you're facing. And that may be when there's a lot of uncertainty Uh uh, and you and you're dealing with something for the first time and you don't really know what's going to happen, our body errs on the side of overproducing energy. And then the more we encounter that situation again and again, and we get and we learn more about it and the types of things that are likely to happen, our body gets better at producing the right amount of energy and it's less likely to overproduce.

And so what what we we might intuitively understand that is like learning how to self-regulate. But I think if you go into the nuts and bolts, it's uh it may be more insightfully viewed as the body learning more and more about this situation uh and and learning the appropriate level of of energy that is needed to to deal with this with threat. And in the beginning, it may overproduce, you know, because you know it's it's more costly to underproduce than than overproduce. Um but uh as as you learn more and more, you get the balance right. Um anyway, that that was the s the sort of hypothesis that we were throwing out with with Colton. I'm sure I'm curious if if you find that plausible. Yeah. Yeah, it's very plausible.

Um and it's you know it's it's also related to sort of what I was talking about earlier, with cortisol being responsible for destabilization of neural networks, um, but also reconnection. Um, and so what on a neural level, what that looks like is now you have this synaptic pathways um to be able to quickly and and um easily, you know, sort of um deal with that particular threat, um, whereas you didn't before. Um and had you not, you know, had you not had that reaction, you wouldn't have had you know the energetic resources to be able to sort of you know disconnect those ineffective neural networks and reconnect more effective ones. I wanna get your take on on something that still puzzles me and that I find kind of

mysterious as about stress. And it seems to me that there are that stress is kind of poor this is maybe this is an illusion and maybe it really is well designed, or if if this is a an example of mismatch. But it seems like for a lot of the things that stress us out, we don't really need to burn a lot of energy. And in fact, in many cases, it could be counterproductive to burn a lot of energy. So if I'm stressed out about a math test that I'm gonna take tomorrow, it seems like I don't really need a lot of energy to deal with that challenge. I don't, you know, I'm not gonna be running a marathon, I'm not gonna be um fighting with anybody physically. All I need to do is just remember the damn information and then regurgitate that

information on the test. Uh it seems like you know, burning a bunch of energy is just not going to help me deal with that challenge. In fact, it could uh impair my ability to deal with that challenge insofar as it prevents me from sleeping uh and actually, you know, retaining and consolidating the information that I've learned uh and and and being cognitively capable the next day. It seems like there are a lot of examples like that where our body is burning a lot of energy to deal with a challenge that is fundamentally cognitive rather than physical. And yet the the body is treating it as if it were physical. And to me that seems kind of maladaptive. It seems like the body should be good at uh estimating when it's necessary to burn energy

and when it isn't. It should be stingy with with uh investments of energy. Do you am I missing something here? Is there is there hidden design here that I'm not seeing? Is this a an example of mismatch? Uh wha what what what is your take on this? No, I think that that's a great point. Um it to so it's both. Um to some extent it is mismatch. Um I think, but what you just described is sort of, you know, um very consistent with like Sopolsky's view um of the human stress response anyway, as being just basically like just overshooting all the time. And we're, you know, sort of misinterpreting these social situations as as being really impactful. I think I would argue that, you know, being, you know, sort of, you

know, way super stressed over a math test is probably not a great use of your resources. But what you're what we're cueing on are these much more, you know, sort of older sort of perspectives of, you know, the way that others view me is important. And it's important as far as what skills I'm bringing to the group, how valuable I am as a coalition member. And so these social evaluative sort of threats are, you know, you know, should be, should reliably activate the stress response system. Now, do we overshoot? Absolutely. We do. So I, you know, we've done a study with um students in uh speech classes, um, for example. They they um you know know, mount this beautiful stress response and also an immune

response to giving a stress in front of their class. Now, nobody, I mean, you know, I haven't heard of anybody, at least at my university, of like, you know, throwing daggers or anything like that at people that either, you know, do well or don't do well, you know, um in their speeches. But I think what that's cueing on is this sort of, you know, what others think of me is important um and my performance is important. And so what the stress response system is doing there is motivating you to prepare, motivating you to better your skill set. Um so if you think about, for example, um, you know, if you weren't if you weren't stressed about the math test, um, would you study? You know, um, does this, you know, sort of motivate you towards or away from important

outcomes? Yeah. Um uh I'm I I could I'm gonna make a comment about Robert Sapolsky, but I'm not gonna do that. So um uh but what I'm gonna push back against the idea that we're overstressed too much, which is if you imagine the and I don't know if this is true, but if you imagine like the correct design of the system, there's there's two principles. One is there's sort of an error management perspective where if the whole point of stress is the situations detected where there are not sufficient resources to deal with it, it's necessarily by definition, there's the a curve a state initially of activating more than had been previously, and that is probably activating more systems than even will

be in the future. So, for example, I'm learning how to rock climb. The moment I get to a difficult situation, I get really stressed and scared. Now, though, a lot of that stress and scared response is an error in the sense of when I become a really good rock climber, what that stress and scared response eventually causes me to do is a subset of all the systems that get turned on when I'm initially as a beginner scared and stressed. But the issue is I don't know that yet. And so there is definitionally like a turning on more of many systems. So you would think, even just baked into the design, it's going to look overactivated to the extent it's turned on, because the whole point of turning it on is to go through and

test do we need the system? Yes or no. And until the job of the stress system is to like wake everybody up in the mind and sort of go through and be like, are you going to be useful in this situation? Yes or no. And the process of waking everybody up is gonna look unefficient and overblown because that's the point, is you don't know who's gonna be relevant or not. And the second thing is, um, and I'm curious what you think about that. And the second thing is you could also imagine a good design feature would be to scale to the variation. So I think an a concrete way to put this would be yeah, why are kids worried about math tests if they were in combat? They would think like worrying about the math test would be stupid.

But you would imagine that, yeah, if you put a person in combat, it would rescale to what is the most important thing right now. But that's a design feature, right? Like it's like it we shouldn't be designed to sort of say, well, what's the range of stress every human on earth is experiencing? And then I should put myself objectively on that scale. No, if I'm a rich brat and like the worst thing that can happen to me is like my filet mignon isn't made the way I want it. I mean it sucks socially and like morally we can like poo poo that. But like it seems like a well evolved design system to sort of be like, look at the range of likely things and then like the things that are the worst, you have that system.

Why wouldn't you use that system? So like I actually would push back against that it's a bad design. I can you can see why people would moralize that, but it it strikes me as actually a really good design to sort of just um use up the variation that the system is experiencing um in that way. Yeah, no, absolutely. And that's you know, I do disagree with Sabolski on that. Um, that it's you know, um, this bad design. It's it's perfectly well designed. Um, that's exactly what you would expect, is to, like you said, sort of recruit all of these systems in a novel situation. Um, and you know, when we experience novelty, then that's you know, sort of all systems go. um, when it's a more familiar or habituated you know sort of context, um, then you know

there's there's less need to sort of re you know recruit all of these um different resources. Yeah. And I mean I will I I will say like as a parent, you know, I'm all the time with my son. I'm like, oh you don't have to react this strongly. So like I, you know, I take my science hat off. But I can see I can see both sides. Yeah. Yeah. Yeah. Absolutely. But you know, I on yeah, on some to some extent there, you know, this these mismatches um do, you know, sort of um there there's a point there, right? Um, and that, you know, yes, we, you know, we it's probably adaptive to get at least a little stressed over the mass test, um, because that's that's gonna lead to some important outcomes later. Um, but at the same time, we have the ability now to socially compare ourselves to groups

that are, you know, uh infinitely more um larger than um in our evolutionary past. And so I think that that then sometimes can create a mismatch. Yeah. I think a lot of advertising or uh in the marketplace of sort of attention. The people some people have called this sort of what is it like an attention market, where really what's being um sought is people's time and attention now. That's evolutionarily recurrent stressors are really, as you would expect, really good at capturing attention. You know, like one thing I always think about is I remember what the Weather Channel used to be like and what it's like now. And I like if I look at the Weather Channel website, I'm like convinced that like there's

going to be like apocalypse any day now. And you know, 15 years ago it wasn't like that. And I just view that as sort of a result of this market of needing people's attention. And one can make an argument that a lot of news and a lot of political discourse is like that too. So I actually I I wonder, um, or I would imagine the stress system or understanding its inputs is actually going to be really important for understanding um these larger issues of what social representations or content gets um public or people find interesting even. Uh-huh. Oh yeah, absolutely. Um yeah, don't tell um some of those companies at Instagram and and things like that. They could definitely recruit Well, they're already doing it.

Yeah, but I would think the basic science would correct against it and be like, look, they're actually using our endocrine system against us. Um and and that's part of why they're doing what they're doing. They probably don't know that they're doing it. That's just they're just A B testing, right? Yeah, yeah, absolutely. But that's, you know, that's and you know, on social media, that's why, you know, sort of, you know, things are sensationalized and and you know, this rage, like we we pay attention to things that are enraging, right? Why would why are we doing that to ourselves? It's ridiculous. Um, and a lot of times these are things that don't impact us on a day-to-day basis. Um, but we are still, you know, sort of recruiting this, you know, absolute rage at these

people and spend hours online, you know, arguing with strangers who we'll never meet and we'll never, you know, sort of have, you know, these um interdependent um relationships with. Um, but I think it's a it's just a design of the human mind of, you know, when this content is in front of me, um, so it must be important. It's interesting. I mean, when I when I think about stress, I I usually think about it in terms of its effects on the body. Um, you know, your heart races, your muscles tense up, your blood pressure increases. Um, but I haven't it's hard for me to wrap my hand around, you know, the fact that it might also impact the brain. Um is there thing are there things that the brain can do when

it gets a jolt of energy from a stress response that it could not have otherwise done? Does stress uh change cognition? Does it change neural processing? Uh is is in some ways do we need energy to cognitively deal with the challenge as well as physically deal with the challenge? Yes, absolutely. I mean, it regulates attention, right? Um it regulates arousal and attention towards, you know, one stimuli over another. You know, how do you prioritize all the stimuli in your environment? Um, that's that's part of what what does that um overall. So, um, and yeah, it it definitely gets this bad name because a lot of times we we have this icky feeling um when we feel that way. Um, but again, it's it's you know, it's really sort of, you know, working with these neural

systems um to in in order to sort of you know help us attend to things that were you know recurrently threatening um perhaps or recurrently rewarding as well um yeah that's yeah no oh yeah David go ahead yeah I I'm just curious like what so like why why the brain needs energy to pay attention. Like in theory you could imagine the brain just you know just you know uh turns on the the attention networks and focuses on focuses on on this particular type of information in theory that shouldn't require any more energy than being distracted or unfocused. And yet it's it seems to be related to how energized you are and how focused you are. Is there something about attention that requires energy or is that or is energy intensive?

I mean, just riffing about it, well, I'm thinking about it right now, like it could be that it takes energy to suppress systems that would otherwise uh take your attention away. Like um, you know, for example, if your stomach is empty and you're hungry if you're digesting or something, like that could just pull your attention away. And it takes some energy to shut down uh the that system. The process. You know, your your your feel your cravings, your appetites, your, you know, the the feelings going on in your stomach, like your digestive system. Like I know stress has effects on appetite and digestion. And it could be that the reason why attention requires energy is because it takes energy to to shut things down and suppress them.

Did you do you buy that logic or is there something else going on in the relationship stress and attention? Yeah, absolutely. You have to inhibit things that are at least in the in the moment not immediately important. right? Um, and um that does take quite a bit of energy and you know, sort of prefrontal cortex activity um to be able to sort of, you know, uh again, sort of, you know, decide which which is a priority. Um, let's let's not worry about digestion right now, um, because you know, there's a spare coming or, you know, um, whatever, or, you know, I have to I have to give uh a a talk um and uh that sort of thing. So I need to allocate my my energy resources and and you know, neural networks cost cost a

lot um they cost a lot of calories they're very expensive um so if you just think about it on a you know sort of cellular level um they're requiring energy to to fire even inhibition it's it's not just excitatory processes it's inhibitory processes also it it might also be the reverse um too which is that if there's a detection of an important situation, like a bear, or I'm about to give a talk, there's a lot of energy allocated to like just neck down stuff because it's important. But it's that the that's co-occurring with then the strong shift down in attention. And the idea is that such a strong shift or focus and attention is co-occurring with the detection of such an important situation that it uh um that

that shutdown in attention is worthwhile, right? So, so it might just be like it's sort of like Rob Kurzman's idea of like, why do we have an experience of mental effort? It's not that there's any more calories used up by something that feels effortful or not, but there's an opportunity cost. And so that should be detected. So it might be that like we're aware of a real shutdown in attention. Like, oh my God, I, you know, I was performing on stage and I wasn't even aware of the crowd, you know, like I was just in the zone, or like, you know, I saw the bear and I didn't even think about what I was doing. Like we have this experience, but I but it but I wonder if it isn't that it it is more energetic, it's just that it's only in those situations that are really

important that that are evolved psychology really directs attention very strongly, those also sometimes require energy too. But it's not that it's actually an energetic requirement. It's just that it's an important enough situation that it's worth reducing attention and most of the time it's not. And we're just aware that it's sort of weird um that our attention has been narrowed so much. Does that I don't know if that makes sense? Is that does make sense? Um to some extent. It's it's sort of a um, you know, yeah, uh going at it from from a slightly different angle. But yeah, it's uh we're using the same amount of energy, it's just how it's allocated. Um and most of the time we're not you we're not really aware of how our energy is is

allocated unless we have this, you know, sort of system that is making it more more apparent to us. I want to throw another hypothesis out. I mean, could it be that um the restructuring of our neural networks is energy intensive. You mentioned earlier that stress can affect uh brain networks and can uh damage certain neural pathways. Um could it be that, you know, if I'm in a really important situation that I need to pay really close attention to and remember every single detail of it and totally uh revise my plans and strategies uh and and you know into the future, then I'm gonna have to restructure my brain a lot during that moment. Uh, and that itself requires energy. I have to construct new neural networks.

I have to take in this information and uh, you know, uh store every detail of it so that I can use it later on, and so that I can use it to totally reorient uh my behavioral strategies going into the future. And so, could it be that the restructuring of brain networks and the retention of the information and the and the use of that information to guide long-term behavior is itself energy intensive. And that might explain the link between stress and attention. Yeah, yeah, absolutely. And, you know, um, that's the thing, is that you we can look at that one way as like, you know, if you think about a stressful situation or maybe, you know, um social evaluative, maybe not you're you don't feel super stressed, but you're you know very roused and you

know, very attentive to the situation. Um, afterwards you feel hungrier than you would have otherwise, right? Um and so it it there is that sort of process of of sort of, you know, I I expended some calories somehow. Um you did something. Yeah. And I like I don't this is all anecdotal, but like, you know, after I'm done teaching, for example, I'll just be like compulsive for an hour, you know, like in a way that if I hadn't been, you know, or just like I feel like I need a break. I just need to like and I don't know what I don't know what that is, and I don't know if there's like a good account of that, but I I feel like people talk about that a lot. We're like, you know, oh, or I didn't realize how stressed I was, but now that I'm coming

down, I just need to relax for a while. Like, I mean, you can see how people have this like hydraulic model of things, but I mean clearly there's something to that, right? Like so I um, yeah, there there's still mysteries there in terms of describing sort of what what that means at a computational level. Like why do people have that? It's certainly a real thing at every scale, right? Like people come out of a super high stressful abusive relationship and they just like they have to unwind and they're, you know, like every scale of whether it's teaching for an hour or a year-long stressor or multi-year stressor or whatever. Um, it's interesting. And I feel like sometimes people poo-poo that hydraulic model thing, but I think there's

something to it, but I don't know what would be going on there. Yeah. Yeah. No, I do think there's something to it. I don't think we understand it very well. And I think that goes back to, you know, sort of what you mentioned earlier is this mind blindness, right? A lot of this is happening, you know, on a very implicit level. Um, we really only bring it to explicit awareness when it's absolutely necessary. Yeah. It's really interesting. Um, some of this stuff starts to touch on things like you know um school performance or obesity or discounting the future, sort of things that as we as citizens or as social institutions sort of train people, we run up against the fact that people have adverse social situations,

they get stressed. And then we're dealing with phenotypes that vary in how designed for a stressful environment they are. And I know some of your research has sort of touched on things like social adversity, and obviously it's a big political or social issue, as you would expect, right? Um can you talk maybe at least or give some uh flavors of what what those some of those areas of research are, what you've discovered that might be surprising to people, or just people who don't know the work? Yeah. Um, so it's interesting um to to me um that development has any sort of signature on, you know, the adult phenotype. And so just, you know, sort of starting from that perspective is why would we, why would we

sort of, you know, calibrate our our, you know, attentional systems, our stress response systems and things like that in a childhood environment, you know, to something that's, that's um going to happen later. And, you know, there there's debate in the field about, you know, sort of the predicted value of childhood versus adult environment in our evolutionary past or even today and things like that. But one of the things that we found most is that all adversity isn't the same. And so, you know, sort of I'm talking about, you know, like if you're just in a low resource environment, yes, that's adverse. Um, that's not fun. Nobody wants to be there. But that doesn't leave the same signature on the stress response system as, say, an

unpredictable social environment And so kids that are coming from, you know, sort of these more, I don't know, I don't want to use a value judgment, but chaotic is a lot of times the term that's used. These, you know, homes that are, you know, unpredictable, basically. Um they um maybe, you know, parents are unpredictable in their behavior, the resources are unpredictable, um, you know, those sorts of things, they seem to show a stress response system that's calibrated to that unpredictability. But what that does is that then pulls back, you know, you mentioned, you know, sort of future orientation that pulls that back to be able to, you know, develop that as a skill or something that is even worth developing, you know, your energy towards and because

become much more, you know, sort of present focus, reward focus on you know what what's happening um in the immediate. Yeah, that makes sense given the design of the system. You're basically what you're saying, if if I understand correctly, is that if the whole point of the stress system is uh what's currently happening, you're not prepared for. And if the environment is non-stationary, meaning it's moving constantly moving, you're basically just telling the stress system you're gonna have to be active a lot. It's not rational to expect that the way the environment is today is gonna be like, you know, it's I'm just it's obvious I'm saying out loud. But yeah, no, it makes sense that that would that would be the case.

Um, and I guess in a world where um, you know, if you wanna be a good worker in the widget factory and you want to be a good, even just collaborative partner, it's ideal to have somebody who whose calibrational settings are at least stable or not discounting the future to the extent that discounting the future means they might be more likely to want to exploit you for good or fair or not fair reasons. Like you can see where um social friction arises or value judgments come up from the people who have the luxury of not discounting the future sort of look down upon discounting the future. Yeah, for sure. Go ahead. Yeah. I mean it it it it's making me think of a a metaphor of like if you're on a a sailboat and

there's really tumultuous and unpredictable weather such that there could be a storm at at any time, you're gonna want to have all hands on deck, you know, for most of that time just in case there's a huge tidal wave or there's a huge storm and you need to you know throw water out of the boat, right? But if you can perfectly predict the weather. Even if it's really bad weather, even if you know there's going to be a storm at this exact time for three hours, you can just sleep and then you can just be prepared for that storm. And so it's not really the storms per se that that are going to make you have the all hands on deck response. It's the unpredictability of when the storm is going to come that the n necessitates the

all hands on deck response. Yeah, that's a that's a fantastic analogy. Um really really great. And one of the things that we see too, um, and some of my research has shown is those, you know, individuals from these really unpredictable environments, they don't get stressed over, you know, that we can send them through the trier social stress task, um, and they don't show any response. Um and a lot of it is because their systems are calibrated to um at least in our sample, they there was a lot of neighborhood violence. There was a lot of, you know, just unpredictability even in their young adult environment. And uh so this, you know, yeah, I can come in and you know do some math problems for you,

no problem. Um that's not going to really impact my uh you know sort of survivability. Um but and you know sort of consistent with that we looked at their diurnal stress response. So we you know have an initial stress response in the morning and then it usually sort of declines throughout the day. with these individuals, it was it was sort of the opposite and that they got they ramped it up towards the end of the day. Um initially when I got that finding I couldn't really understand what was going on. Uh right it was like, you know, again, are are their systems just broken? Are they, you know, uh what are they doing? But if you look at their context, when are the things that are most likely um that are

going to be bad to for you to happen in the evenings, right? Um if you if you're living in these, you know, sort of more violent neighborhoods, um, and you know, things like that, that's that's when, you know, um you're you need to be um sort of vigilant. You need to be aware. Um and so yeah, your your um analogy with a sailboat is is absolutely perfect for that. Yeah. Yeah. Um it it also it reminds me of of um some of the work that Daniel Nettle's done on obesity and the unpredictability of food. Um and what he's argued is that um the tendency of the body to store energy in the form of fat for the future is or may be caused by an unpredictability in the available food sources, such that if you're constantly skipping

meals or if you're uncertain about where your next meal is going to come from, or if if at any moment you could just run out of food, then it becomes a really good bet for you to store energy on your body in the form of fat just in case food is going to be unavailable or insecure in the future. Uh, and so he has uh run uh a counter to this mismatch story that the reason why um we have this obesity problem is because we just can't control ourselves and we we shove the Twinkies in our mouth. But he's actually argued that there's actually more logic and sophistication to this system, that it's responding to reliable cues of uncertainty and food insecurity, and it's adaptively storing energy on the body for those kinds of ecological contexts.

I'm curious if if there is any other research to back that up about the relationship between stress and eating and fat storage and obesity. Yeah. No, there is. And you know, also it's very consistent with you know future discounting and and and things like that. So childhood obesity, you know, we we see kids that are more impulsive, they're less able to wait for long-term rewards, you know, um, those sorts of things. The entire system is is sort of calibrated to the here and now, um, you know, because later, um, we'll worry about that later, right? Um to survive this moment um in particular. And um, you can even draw from, you know, like the studies with the Dutch hunger winner um and and things like that.

So those um, you know, mothers when they were pregnant experienced um malnutrition, a lot of unpredictability, and things like that. And they followed them afterwards. And those kids were more prone to developing obesity, more prone to developing heart issues, you know, um, and those sorts of things because the signal that they got was, you know, there's not enough food. Um, and you need to, you know, really downregulate your metabolism um in order to take advantage of the calories that you do receive. Yeah. It's an it's an interesting thing too, and this comes up uh buses back to the magic point where I the the fact that our endocrine system interacts with our brain is really interesting. I mean, again, it's sort of stupid that I think that's interesting, but but it is because

somehow our brains know how resources are unpredictable, right? Or I mean, so it for example, you might say, well, like maybe, you know, if my how often am I hungry? That feels like a very physiological thing. But there's a lot of things like social cues. There's probably a lot of cues of like how often do I see food? And if you don't believe that, well, like look at all the social reactions. Like, you know, you're not getting punched a lot, you know. And even if you are, like it matters whether or not somebody was like intending it or not. But a lot of things are just very abstract social or inner information processing cues of like what's the level of violence or conflict. And somehow this is having an effect not only in our brains, but also the rest of our body.

It's a really fascinating idea that very abstract cues can have a very concrete, even developmental or kind of calibrational effect on us, like how much we're likely to store fat, for example. Right. Absolutely. Well, and that's, I think, you know, reflects the fact that we don't really, you know, not only do we not understand the brain as well as we think we do, um, but we particularly don't understand development and the developing brain like we think we do. Or as much as we think we do, kids are, you know, encoding much more information than we give them credit for. Yeah. Um, to just I would this is something I just bring it back to stress for a second. Um, have you thought about stress differently because of this work?

So for example, like if somebody's listening and they're like, well, how can I help my kids be less stressed? Or like if somebody I care about is stressed, um, is there a reaction that's sort of the a better thing to do, a worse thing to do? Does it really depend on what the stressor is? Because I know like that's always, you know, we don't want our kids to be stressed, but then as you said, we want them to gr build the muscles of dealing with that. Um, do you think differently about stress, or like do you if does anybody ever ask you for like you know advice, maybe quote unquote, uh, or like how to approach stress among people we care about? Yeah. Yeah, for sure. Um, yeah, I get that question a lot.

And um I think, you know, a lot of it really depends on on what the stressor is, you know, um, and then also, you know, what, you know, potential impact. And and, you know, we can talk about how good we are at at you know, sort of um forecasting this, but what potential impact that might have, you know, um on the individual as well. I think, you know, just taking kids, for example, um, a lot of you know, parents want to protect them from any sort of any sort of adversity, right? Um, or any sort of negative outcome. And um, you know, I could take, you know, homework uh as an example of that. Like, you know, parents sometimes will, you know, make sure that their kids do that, you know, homework, or um if they didn't turn it in, oh, can they, you know, can they turn it

in, you know, for a grade now? And that sort of thing. I had with my oldest son, his teacher was actually shocked at a parent teacher conference because I told her, I said, I want you to fail him. I he didn't turn this stuff in. Um, so fail him because otherwise you don't ever learn to sort of mobilize those resources to be able to, you know, sort of make that happen. And then they become student college students that ask for extensions and, you know, um those sorts of things. But on, you know, sort of a bigger level to and particularly now, it's really difficult, I think, for parents to understand or to know what is a threat versus what isn't a threat, right? Um, and that's what you know, a lot of parents make the mistake of, you know, sort of like

not letting their kids play outside, um, not letting them, you know, sort of experience some of these things on their own and having to, you know, deal with challenges of, you know, how do I cross the creek or you know, um, you know, those sorts of things, or how do I stay away from people that might be dangerous or situations that might be dangerous? And um, so they they keep them inside. Well, what are they doing inside? They're going on the internet and they're getting all sorts of, you know, um things that they shouldn't be exposed to and, you know, um that sort of thing. But parents perceive that uh as um, you know, being safer um and that sort of thing. So perception is a big, you know, um component to this, a big key to it.

But I think, you know, sort of with other relationships, you know, um, that you might care about, I think it really depends a lot on, you know, the particular stressor. But what people are looking for is a coping mechanism, right? Um, of of how do I feel better about this? How do I solve this, you know, um particular problem. And to the extent that you can form an allyship or, you know, whatever, um, and and sort of helping them out, I think would would be um better about that. But um, like you mentioned before, it's it's difficult to sort of, you know, particularly in this day and age, to determine what what should I be stressed about. Um, you know, so for example, should we, you know, should we be worried about, you know, um

how, you know, how much our colleagues are making, right? Um there's there's um people that will go in and look at, you know, salaries and um things like that. I would recommend no. Uh Than not being something. But what that's reflecting is that's reflecting a motivation towards, you know, um, towards status driving. Um and so if you could redirect that in a way that is, you know, um more controllable, then you're gonna see the stress response system damn down. So part of it is that the status or not, yeah, well, status is the example, but the stress system, in addition to our current situation, it's also a function of what the plans and goals are. So the same situation might not be stressful to one person versus another because of where

their mental representations of where they're trying to get to are. Yeah. That's interesting. Yeah. Cool. Well, I think we're about uh getting to that time in the episode where we uh ask our canonical question, which is uh is there anything that we should have asked you or that we should have talked about that we have missed? Uh let me think about that for a second. Um sorry to stress you out. Yeah, no. No, because yeah, I know I know because there's lots of like specific studies you've done um too that we haven't really talked about. But I mean people can look on your website too. But yeah, if there's anything or yeah, any any question at all or anything that you're either currently working on or um you know, really yeah, yeah.

Yeah. I think most of my current work, I have, you know, a couple different areas. Um, and um one thing that I think that people don't know enough about, or I don't know enough about, uh, we don't know enough about as a field, is, you know, um to say so I got into sex differences talking, you know, understanding sex differences sort of through this stress response um system interest um and uh that sort of thing, but also an interest about parenting and fatherhood. And so I think that that's you know sort of an area that that people we don't know enough about. We don't know enough about how fathers uniquely impact kids' development. And one of the ways that we think that may um be happening is actually through dads are

more likely to, for example, you know, do rough and tumble play with their kids and you know um things like that. That's sort of a it's a low level, but it's a risk. Um and it's allowing kids to sort of, you know, get experience with, you know, sort of getting really aroused and coming right to that edge of aggression and pulling back and those sorts of things. And so um just you know sort of building from that, I don't I don't think that we know enough about that. And I wish more researchers would would sort of you know get in line with um sort of understanding what you know what is going on with human fatherhood. Um why why are dads even investing in all? And I realize there's a lot of, you know, there's variability in that investment.

Um, but why are you for why are you spending all your energy that way? Um not even, you know, why are you not um, you know, seeking more mates, but just, you know, why are you not just, you know, um spending your energy making more money or, you know, having more fun, doing um things that why are we motivated um in that way? So um so yeah, that's that's you know one area that I'm sort of dabbling in. But interestingly, um, it's really difficult to get dads to participate um in research. Um, even though we know that they're doing all of these things, um, we we can't quite, you know, sort of um get it on an observational level. Um, so yeah, yeah. That's fantastic. Yeah, no, you're preaching to the choir as you're talking to two dads uh of young kids

right now, and uh yeah, no, parenting psychology and dad um yeah psychology that's fantastic we should do like a special issue in eHB or something even if it's totally yeah I mean I I'm curious what you think about uh a change I noticed in myself after becoming a dad. Um I am now after becoming a dad much more likely to cry during movies um like movies that I saw before like I remember I saw Moana before becoming a dad and then after and I did not you know, have much of an emotional response when I first saw it. And then after becoming dead, I was like bawling during the entire movie. Like Yep. Uh your child changed your brain. Yeah, changed my brain. I uh it's it's it's weird. I don't know how to explain like why why crying during movies?

I don't know what that's about, but um it's an interesting response I've noticed in myself. Yeah, I think that reflects, you know, just more empathetic sensitivity. Um and you know, you guys know this. And, you know, when I tell my college students that get very upset and worried about it is, you know, when you're a father, when you become a father, if you are investing, you experience a little decline in testosterone, right? So testosterone is negatively associated with empathy. And so it's probably, you know, an adaptive calibration there to become more sensitive to these social cues, particularly um, you know, of this individual that you're um should be really highly invested in. You can tell them that it's fantastic to experience a decrease in testosterone.

As somebody who I feel like I had an excess of testosterone and I was like miserable, like falling out of my skin and I had it out of the kid and I'm like, this is awesome. I'm like I'm very glad to have less testosterone in my system. Yeah. Like it's it's a um you know parenting the parenting and uh the what what dads are doing and we've had some people on like Karen Kramer or Shina Lu Levy, this this idea that uh this second or third wave evolutionary approach to even even though we have to reproduction is important, the idea that investment in the social and physical capital of offspring really makes a big difference on their success and their status, right? Like we don't question the idea that investing in my own

generation's resources and status is good fitness from a fitness perspective. But there used to be sort of this cartoonish idea that, well, if we just have kids, then that's all that matters. And like the number of kids is all that matters. But if you just follow the logic for yourself, then it's also it matters how many resources your kids have. It matters what their social status is. It's just as much of an arms race their generation as it was for yours. And if you just accept that consistent logic, then it immediately becomes a thing of yeah, you're not going to just necessarily always just invest in mating or maximizing the number of offspring. There's also what's the level of investment in that in the next generation

because they're in an arms race just as much as you are. Yeah, absolutely. Yeah. And what's going to pay off, right? Um, and paying off is is on you know, really developing, you know, socio competitive competencies um in your kid because their status is going to impact, you know, future generations as well. Yeah. I've actually I've always felt as a coalition slash alliance researcher myself, I've always thought that the time course of alliances and the fact that you as an adult currently your alliance structure will fundamentally may or may not survive the future because there's new there's new the kids are gonna grow up I've always thought that was also under emphasized that that the this there must be a psychology of worrying about that of wanting to affect that and I think

that's also something that hasn't been um uh as as emphasized as it needs to be. Absolutely. Yeah. I think history, uh, people uh just this stupid aside, but like I always wonder like why we teach history the first the way we do and when we do. Because I don't know about you guys, but I feel much more interested in history the older I get. But I was taught history very early. And I actually wonder if it's a readout of like the evolved psychology being like we have to indoctrinate the kids early to our history. And it's the expression of wanting our current social narrative to extend. And it's probably not well designed for what kids actually are interested in. But it's yeah, yeah. Yeah. No, there's a huge demand for, you know, teaching kids the values that the parents hold.

Like I see so many children's books that are, you know, preaching these political messages. And, you know, I agree with the political message, but still I find it interesting that there's such a demand for, you know, inculcating kids uh into these values at such a young age. I think it does speak to this um adaptive problem of ensuring that the kids don't grow up to, you know, uh shake up the the political alliance structure uh that was built, you know. Right. Yeah, that's some of it's pretty explicit. Like I've seen uh like I grew up in a religious background. I remember looking, this was years ago, like like for example, like people staying in a religion, like it's very explicit and well known that if you don't get kids early, they

don't stay in it or uh or get in it at all. Like there's very much uh an age time course. Right. Okay. Yeah. Um, well, well, Jen, thank you so much for coming on. It was a pleasure. I feel like I uh it was the perfect combination of I feel like I am a clearer thinker about really important fundamental things, but it also is opening up a whole bunch of mysteries and questions. But I think that's that's the lovely beauty of taking an evolutionary perspective is that sort of the the things we take for granted are actually strange and we just get clarity on that. Right, right. Absolutely. Yeah. Thank you so much. David, this was not a stressful episode at all. No, in fact, it was quite relaxing and enjoyable.

I I I yeah, agreed. Um, if you feel the same, then please uh like and subscribe, social media, Patreon. Um, and uh David, I just want to reiterate how lovely the music is for this podcast. Thank you. I appreciate it. That's very sweet to hear. Yeah. Um, can you remind me how do you do it again? Do you use a you don't keyboard or no keyboard? Uh mouse. So I use Logic Pro. Okay. Um and you can just click a note and then drag it up or down to raise or lower the pitch and I'd copy and paste the notes and put them where I want and amazing. Yeah. Yeah. It's a lot of fun. That's cool. It's called being a composer with on your computer is it's wonderful. It's you don't yeah. What kind of guitar do you have?

I have an acoustic guitar. Mainly because I used to have an electric guitar and it was too annoying for my wife to play. So but she likes the sound of acoustic guitar. Headphones, headphones. You can plug in. What kind of acoustic guitar do you have? Oh, it's right here. I didn't even know. That's fantastic. Oh, it's beautiful. What what what brand is it? Is it fender? I have no idea. I'm I'm on a guitar. Uh could look in the whole sun hole. Yeah. Yeah. Yeah. Okay. Yep, it's a fender. Yeah, I'm not a guitar person. I don't know a lot about guitars, but I just enjoy playing them. Okay. So fantastic. Well, great. Well, maybe next maybe next week, maybe next out for a weekend, you can we can get a little

bit of David on the acoustic guitar or maybe bonus episode. Ooh, yeah. I mean, maybe we'll do that if we like if we get a lot of support from our listeners. Oh, nice. But if we Yeah, that'll be a nice incentive for you guys. Well, we have to do our homework and think about what incentive to dangle in front of us. Yeah, live performance. Yeah, and David Pins off on the guitar. Oh, I like this song request. Oh wow, this is amazing. Yeah, I'll leave I'll I'll write a song about whatever you want. How's that for incentive? Well, now we have to think about when we have the incentive down, now we have to think about what we want from people. Hmm. Uh well, you can give us some money on Patreon. You can say some nice things about us on social media, leave us a kind review.

I think that's about it, right? That is, but it's pretty um vague. Like you have to like if somebody's like, well, what do I have to do personally to be able to be the one to tell David here's what the song should be? Like donate this amount of money, or like, you know get this I don't don't we have to have how about this after your kind review after your kind words on social media after your Patreon donation just say this one's for you David I want that song sounds good all right for whoever whoever gets to that first okay all right uh interesting okay good um I like this direction okay uh and this is how we become a bluegrass band okay all right um have everybody have a good week and we'll we'll see you

with Charles Darwin Um okay. Uh with the AI ghost of Charles Darwin's throwback. We should get we should get an AI to be to like you know read all of Charles Darwin's works and just be Charles Darwin and then just interview him on the podcast. That is weird. That would be pretty bizarre to do, actually. But it might be interesting. I don't know. I feel ambivalently about that. I don't know. That's great. It's an idea. I feel really uh yeah, I feel that's I I'm confident that it is an idea. That's a little stressful. Okay. All right. Uh okay, David. Um I'll see you next week and maybe we'll uh maybe we'll have Charles Darwin and you on the guitar next week. Maybe he'll accompany me on uh on my son.

On the steel guitar for whatever reason. I don't know why. Um right, everybody. Have a good have a good week.