EP #66
Drinking Habits and the Reptilian Brain
listen to
EPISODE #66
Summary
In this episode of the “Alcohol Minimalist Podcast,” Molly explores the evolution of the human brain, challenging the traditional triune model proposed by Paul D. MacLean. Molly reflects on her own journey of understanding neuroscience and its impact on her drinking habits, highlighting the influence of Lisa Feldman Barrett’s book, “Seven and a Half Lessons About the Brain.” She discusses the outdated notion that the brain evolved in layers over time, emphasizing that recent research has debunked this oversimplified view. Molly acknowledges the enduring appeal of the triune theory while presenting modern perspectives from neuroscientists like Terrence Deacon and Dr. Robert Sapolsky. The episode delves into the brain’s role in social reality, dispelling myths about evolutionary processes and encouraging a nuanced understanding of neuroscience.
Transcript
Hey, it’s Molly from alcohol minimalist. What do you do in this October? I would love to have you join me in my more sober October challenge. What do I mean by more sober October, it simply means that we’re going to add in more alcohol free days than you currently been doing, whether that’s one or two or 31. It’s up to you, you get to set your own goal and that’s why it’s more sober October. You can check it out and learn more at get got sunnyside.co/molly It’s totally free. I’ve got prizes, I’m going to be going live every week to announce the prize winners. And it’s just going to be an awesome event. So I would love to have you join me. You can learn more at get.sunnyside.co/molly and you can get registered today. Welcome to the alcohol minimalist podcast. I’m your host Molly watts. If you want to change your drinking habits and create a peaceful relationship with alcohol, you’re in the right place. This podcast explores the strategies I use to overcome a lifetime of family alcohol abuse, more than 30 years of anxiety and worry about my own drinking, and what felt like an unbreakable daily drinking habit. Becoming an alcohol minimalist means removing excess alcohol from your life. So it doesn’t remove you from life. It means being able to take alcohol or leave it without feeling deprived. It means to live peacefully, being able to enjoy a glass of wine without feeling guilty and without needing to finish the bottle. With Science on our side will shatter your past patterns and eliminate your excuses. Changing your relationship with alcohol is possible. I’m here to help you do it. Let’s start now. Well, hello and welcome or welcome back to the alcohol minimalist podcast with me your host, Molly Watts coming to you from well, it looks to be a little cloudy this morning. But you know what? I’m going to take it. We actually lost power for six hours yesterday in the afternoon and evening due to some windy wet weather here. So I guess a few clouds this morning and I can actually see some blue sky poking out behind them will have to be okay. I am also hearing rumors that there are 70 plus degree days in my future this week. So anyone that’s been listening to this show for any length of time knows that’s going to make me super happy. So I am looking forward to that. All right, before we get into today’s episode, I do have a little bit of housekeeping. We have a prize winner this week for someone who has left a review of either the podcast or the book. In this instance, it was for the book breaking the bottle legacy on Amazon. And so Kay girl, I don’t know who you are. But Kay girl, if you are listening, you are our prize winner this week, please email me Molly at Molly watts.com. And let me know that you are the winner of some alcohol, minimalist swag and I will get that out to you. Again, you can be entered into Win win as well just by leaving a review of either the podcast on wherever you listen to podcasts, or by reviewing the book as well either one, and you will be entered to win. So thank you, Kay girl for your kind review. All right, today on the podcast, we are diving into one of my favorite topics again, it’s your brain, well, our brains, my brain to the human brain. And specifically today I’m going to be doing a deeper dive into the triune brain model. One of the fundamental things I’ve tried to do with this podcast is to present science from a full 360 degree view. For example, I’ve often talked about understanding the limitations of the research that has been done with regards to alcohol. And why we can’t accept headlines like study shows that red wine is good for your heart at face value, because the studies are often correlation, not causation, and they’re not double blind, placebo controlled studies. And so there’s reasons that we need to take the science that we read about alcohol with a grain of salt. And I’ve also shared a lot of neuroscience research because understanding some of the ways my brain works definitely helped me refute some of my own long standing self limiting beliefs about my ability to change Ah, my drinking habits. And it’s very clear, of course, as well that alcohol affects our brain chemistry, which is another piece of brain science. So, again, for me, it’s always been important to understand the science. And this knowledge really helped me correct my thoughts about alcohol, which in turn changed how I felt about drinking. So I could take different actions and actually change my drinking habits. Now, none of this is up for debate. The thing about neuroscience is that we’re constantly learning more about the brain. So the science literally changes all the time. And we have to be flexible, and be willing to reevaluate our own literacy, when it comes to science in this particular field, really, when it comes to our literacy in science in any field. All right. But the question Do you really have a reptilian brain has been bothering me, it’s been bothering me first, because I hear a lot of coaches, and self help leaders talk about the lizard brain, or our more primitive lower brains. And I definitely have to obviously, if you’ve listened to this podcast, you’ve heard me talk about the lower brain. I’ve talked about the human brain as having evolved by design to seek pleasure, avoid pain and conserve energy. And while that basic premise that brains evolved over millions of years is true, and that different species, including humans, and the mammals, evolved in different ways to perpetuate each species is fundamentally correct. It isn’t necessarily accurate to say that the brain is compartmentalized or structurally specific, with certain areas involved with emotion and other areas only involved with thinking that isn’t true. The prefrontal cortex is involved in the emotional responses and the Olympic system is also a while not involved in cognitive function, you can’t think without including your limbic system. But this idea that we evolved with emotion and then involve this cognitive processes later, that was certainly what I believed, and what I’ve kind of set on the podcast for sure. Well, I found myself at a crossroads recently, when I was confronted with the ideas in a book called Seven and a half lessons about the brain, by Lisa Feldman Barrett. And here’s what she says about the triune brain model. Quote, it’s certainly a compelling story at at times, it captures how we feel in daily life. For example, when your taste buds are tempted by a luscious slice, a velvety kick chocolate cake, but you decline it because honestly, you just finished breakfast. It’s easy to believe that your impulsive inner lizard and your emotional limbic system pushed you in a cake word direction, and your rational neocortex wrestled the pair into submission. But our human brains don’t work that way. Bad behavior doesn’t come from ancient and unbridled inner beasts. Good Behavior is not the result of rationality, and rationality and emotion are not at war. They do not even live in separate parts of the brain. Alright, so if you’ve listened to this podcast before, you’ve heard me talk about the triune brain model, and how learning about the brain and understanding the brain’s evolutionary path helped me figure out how to break what I believed was an unbreakable daily drinking habit. To recap what the triune brain what the triune model says. The concept behind the triune brain or reptilian lizard brain was proposed back in the 1960s by neuroscientists Paul McLean. McLean suggested that the human brain is divided into three layers that each emerged in succession in the course of evolution. The oldest the reptilian brain, or our complex controls basic functions such as breathing, body temperature and heart rate. Next, the limbic system controls emotional responses. And finally, the cerebral cortex controls language and reason. Now, I will also tell you that I recognized and recognize still that the triune brain model is outdated and newer, more sophisticated models of the brain exist. In fact, in my own book, breaking the bottle legacy, here’s how I described it. In the 1960s, American neuroscientists Paul McLean introduced the triune brain model. He detailed this model in his book published in 1990, and titled The Triune brain in evolution. In it he described IPS the brain has three distinct structures that evolved over the course of humankind. He described the three areas of the brain in terms of an organizational hierarchy, beginning with the most basic of functions such as breathing through higher order conscious activity like metacognition previously mentioned. While more recent research has shown the model is over simplified, it does provide a very good foundation for understanding brain functions. In my journey to unwind my own drinking habit, I found this model explained much of the why and how I had created my drinking habit. It also put the power to change that habit in my control. As I say, right there, it was foundational. And the triune theory has been foundational, even for the neuroscientists of today who’ve gone on to debunk it or show that it is incorrect in terms of evolutionary process. Here’s what Wikipedia says. The triune model of the mammalian brain is seen as an over simplified organizing theme by some in the field of comparative neuroscience. It continues to hold public interest because of its simplicity. While inaccurate in many respects as an explanation for brain activity, structure and evolution. It remains one of the very few approximations of the truth we have to work with. The neocortex represents that cluster of brain structures involved in advanced cognition, including planning, modeling and simulation. The limbic brain refers to those brain structures wherever located, associated with social and nurturing behaviors, mutual reciprocity, and other behaviors and aspects that arose during the Age of mammals. And the reptilian brain refers to those brain structures related to territoriality, ritual behavior, and other reptile behaviors. The theories conceptual beauty and intuitive appeal have lent it enormous staying power. It is still covered in many textbooks and course lectures in biological psychology. But according to Terrence Deacon, PhD, an expert on the evolution of human cognition at the University of California, Berkeley, subsequent research has revealed that McLean’s basic premise his hats on top of hats view that brain systems were added by accretion over the course of evolution was mistaken. Adding on is almost certainly not the way the brain has evolved, said Deacon. Instead, the same structures have become modified in different ways in different lineages. Deacon continues to stay about McLean that he was really the model of the move towards understanding the brain in evolutionary terms. A lot of our contemporary advances right on top of his work, even though in hindsight, it was misleading. That happens a lot in the sciences, he says, and we don’t often give credit to the false starts that really push us along the way. Hey, everyone, just a quick break here in the show to talk with you about Sunnyside. Sunnyside has partnered with me and I am super excited to share this company with you. I’ve actually had the founders on the show before and I will link that in the show notes so you can hear a little bit from them. Sunnyside is an app that helps you cut back on your drinking or simply build healthier drinking habits. I have watched the company grow over this last year and I’m so impressed. They are deeply mission driven and they are building a service to help millions of people create a healthier relationship with alcohol and they’re doing it without the pressure to quit or feel guilty. So of course you know it aligns with everything I talk about here at alcohol minimalist. Think of Sunnyside as a digital coach that helps you set the plan for the week and provides tools to track your drinks and measure your progress. All while using proven behavior change techniques to create a lasting habit change. It’s super easy to start super easy to stick to and it includes a 15 day free trial so you can test it out. Really it’s worth checking out. Head on over to sunny side.co/minimalist To get started today. For me, the triune model served as a model that encouraged my interest In neuroscience, it helped me understand that my drinking habit was not the result of some pre wired genetic disposition, but simply a learned response that I had unconsciously taught my brain. Now, I have since learned more about the brain and I understand that there are limitations to the triune model, especially if you are focused on it as some sort of anatomical description of evolution in the brain. Why is that a problem first, because the triune model implies that evolution is a linear progress with one organism evolving into the next, ie lizards turned into mice turned into monkeys turned into humans, and mammals did not evolve from reptiles, mammals and reptiles share a common fish like ancestor. The correct view of evolution is that animals radiated from common ancestors within these radiations complex nervous systems and sophisticated cognitive abilities evolved independently many times. Another reason it’s a problem. The cerebral cortex is not unique to mammals, because reptiles fish and birds have a super cerebral cortex too. So this idea that, you know, it wasn’t until the later stage mammals and humans that we got this big cerebral cortex is not true. Other other mammals and fish and reptiles have a cerebral cortex as well. And third, the brain did not evolve with more sophisticated layers built over simpler layers. The notion of layers adding to existing structures across evolutionary time as species became more complex is simply incorrect. So according to Feldman Barrett in the book, seven and a half lessons about the brain in McLean’s day, scientists compared one animal brain to another by injecting them with dye, slicing them paper thin like deli meat and squinting at the stained slides through a microscope. neuroscientists who study brain evolution today still do this. But they also use newer methods that allow them to appear inside neurons and examine the genes within, they’ve discovered that neurons from two species of animals can look very different that still contain the same genes, suggesting that those neurons have the same evolutionary origin. If we find the same genes in certain human and rat neurons, for example, then similar neurons with those genes were most likely present in our last common ancestor. Using these methods, scientists have learned that evolution does not add layers to brain anatomy, like geological layers of sedimentary rock. But human brains are obviously different from rat brains. So how exactly did our brains become different? If not by adding layers? It turns out that as brains become larger over evolutionary time, they reorganize. Scientists have recently discovered that the brains of all mammals are built from a single manufacturing plan, and most likely the brains of reptiles and other vertebrates follow the same plan. The common brain manufacturing plan begins shortly after conception. When an embryo starts producing neurons. The neurons that form a mammals brains are created in an astonishingly predictable order. The ordering holds true for mice, rats, dogs, cats, horses, anteaters, humans, and every other mammalian species studied so far, and genetic evidence strongly suggests the order holds for reptiles, birds and some fish. Yes, to the best of our scientific knowledge, you have the same brain plan as a blood sucking lamprey. If the brains of so many vertebrates develop in the same order, why do these brains look so different from one another? Because the manufacturing process runs in stages and the stages last for shorter or longer durations. In different species. The biological building blocks are the same, what differs is the timing. For example, the stage that produces neurons for the cerebral cortex in humans, runs for a shorter time in rodents, and a much shorter time in lizards. So your cerebral cortex is large. A mouse is a smaller and an Iguana is is tiny, or non existent. It’s debatable. That was a quote directly from seven and a half lessons about the brain. I see value and understanding why the triune model has persisted. And there are many leading scientists including Stanford educator and neuro endocrinologist Dr. Robert Sapolsky, who is the author of the award meaning both behave the biology of humans at our best and worse, which was just published in 2017. He believes also in the value of the triune theory as, quote, a highly schematic and conceptual view of the brain that helps us understand human behavior. So Polsky explains, the brain is insanely complicated. everything connects to everything, a gazillion little sub regions. Amid all that complexity, functionally, it’s very easy to think of the brain as coming in three functional layers. This is a broadly simplified way to think about aspects of brain function when it becomes to behavior. This is highly schematic, the brain doesn’t come in three layers. But one can think of it first most, the bottom most, the most ancient as being what’s often termed as the reptilian brain. It’s located at the base of the brain, and it’s responsible for all of the regulatory stuff. On top of that, is conceptually what can be termed the limbic system, the emotional part of the brain. This is very much a mammalian specialty, this part of the brain connects emotions to behaviors that perpetuate the species. Sitting conceptually, not literally, on top of the limbic system is the cortex. Now, everybody’s got a little bit of cortex, but it’s not until the primates that you have tons and then apes, and then us. There’s a YouTube video, which I will link where Dr. Sapolsky does a fantastic job of showing how the triune model serves to help us understand how all three of the areas can influence each other. And perhaps most importantly, how we can use cognitive functions to influence more autonomic behaviors of the brain. And as a side note, there’s actually a website called Robert Sapolsky rocks.com, where he you can watch a bunch of his lectures from Stanford, and it’s absolutely brilliant. I’ll link that too. But suffice it to say he is among the most renowned behavioral scientists. And yet he shares things in a way that is down to earth and even funny. So what else can we take away from the triune model? First, we can accept a few general ideas, for example, that some structures in our brains are older than others, from an evolutionary standpoint, and that our emotions involve some relatively primitive brain circuits that have been preserved over the course of mammalian evolution. The fear circuit and the pleasure circuit, for instance, are specific neuronal circuits that form what might be best called not our emotional brain, but rather our emotional neuro networks. In short, if we want to continue associating the term limbic system with the emotions, then we need to redefine this term so that it includes the circuits specific to each emotion. The switches in these circuits consists of structures such as the amygdala, the nucleus accumbens, the hippocampus, the hypothalamus, and the thalamus, and certain areas of the prefrontal cortex and the temporal cortex. And no doubt other structures are involved that remain to be discovered. So again, we’re not taught you know, the limbic system or the emotional neural networks, which I like, includes both your frontal cortex, your prefrontal cortex and your temporal cortex, in addition to all those other structures that are typically known as the limbic system, just like real scientists and researchers, further study further education in psychology and neuroscience has helped me continue to evolve my understanding about the brain. And that’s important because I truly believe in the power of neuroscience to help everyday people like you and me, live our lives to the fullest, I find the human brain to be completely fascinating. And I know I’m not alone. I also know that studying neuroscience requires us to be ready to think again, or rethink what we might have previously understood. It’s been like that for decades for for centuries. It wasn’t until the last 40 years that neuroscience and our ability to more effectively study the brain has really exploded. And although we’ve made progress, there is still so much to learn. The brain is among the most complex systems known. And there are many important functions that remain a mystery, such as how memory is stored, how the brain processes information, how many types of neurons exist, and why people develop brain diseases like dementia. Today with cutting edge nature inspired technologies, we are entering an accelerated era of discovery about the brain. Scientists can now look at the cells living inside living brain control the actions of specific cells with light and correct errors in the cells responsible for brain function. Many big questions will be answered by scientists who turned to nature for inspiration. I will leave you with the epilogue from seven and a half lessons about the brain, I will link it in the show notes. If you want to pick up a copy for yourself. I definitely appreciate the way the information is presented in that book, and I see value in moving away from the triune model of brain evolution. I also understand that having a human brain allows me to harness the network of neurons that make up my own brilliant human brain to create the life and experience the mind that is mine. And that alone should give you hope. Quote, once upon a time, you were a little stomach on a stick floating in the sea. Little by little you evolved, you grew sensory systems and learned that you were a part of a bigger world, you grew bodily systems to navigate that world efficiently. And you grew a brain that ran a budget for your body. You learned to live in groups with all the other little brains and bodies, you crawled out of the water and onto land, and across the expanse of evolutionary time. With the innovation that comes from the trial and error and the deaths of trillions of animals. You ended up with a human brain, a brain that can do so many impressive things, but at the same time, severely misunderstands itself, a brain that constructs such rich mental experiences that we feel like emotion and reason wrestle inside us. A brain that’s so complex that we describe it by metaphors and mistake them for knowledge. A brain that’s so skilled at rewiring itself that we think we’re born with all sorts of things that we actually learn a brain that’s so effective at hallucinating that we believe we see the world objectively, and so fast at predicting that we mistake our movements for reactions, a brain that regulates other brains so invisibly, that we presume we’re independent of each other, a brain that creates so many kinds of minds that we assume there’s a single human nature to explain them all. A brain that’s so good at believing its own inventions, that we mistake social reality for the natural world. We know much about the brain today, but there are still so many more lessons to learn. For now at least we’ve learned enough to sketch our brains fantastical, evolutionary journey, and consider the implications for some of the most central and challenging aspects of our lives. Our kind of brain isn’t the biggest in the animal kingdom. And it’s not the best in any objective sense. But it’s ours. It’s the source of our strength and our foibles. It gives us our capacity to build civilizations and our capacity to tear each other down. It makes us simply imperfectly, gloriously human. All right, that’s all I have for you this week, my friends. Until next time, choose peace. Thank you for listening to the alcohol minimalist podcast. This podcast is dedicated to helping you change your drinking habits and to create a peaceful relationship with alcohol. Use something you learned in today’s episode and apply it to your life this week. Transformation is possible. You have the power to change your relationship with alcohol. Now, for more information, please visit me at www dot Molly watts.com