Understanding & Controlling Aggression
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Welcome to the huberman lab podcast, where we discuss science and science space tools for everyday life. I'm Andrew huberman and am a professor of neurology and opened ology at stanford school of medicine. Today we are discussing aggression.

I'm going to explain to you that there are several different types of aggression. For instance, reactive aggression versus pro active aggression, meaning sometimes people will be aggressive because they feel threatened, or they are protecting those that they love who also feel threatened. There's also proactive aggression where people go out of their way to deliberately try and harm others.

And there is indirect aggression, which is aggressive, not involving physical violence for incense, shaming people and things of that sort IT turns out that there are different biological mechanisms underlying each of the different types of aggression. And today I will define those for you. I'll talk about the neural circuits in the brain and body that media ate each of the different kinds of aggression.

Talk about some of the hormones and peptides and neural transmittals involved. I promise to make IT all accessible to you, even if you do not have any biology or science background. I also discuss tools, psychological tools and biological tools that one can use to Better control aggression.

Now, right here is the outset. I want to acknowledge that any discussion about aggression has to have an element of context within IT. To be fair, human beings invest a lot of money, a lot of time and a lot of energy, and indeed can even derive pleasure from aggression.

Later, i'll talk about neural circuits in the brain and body that reinforce in other word's reward through the release of chemicals that make people feel good acts of aggression. However, what are mainly referring to is the context in which human beings will pay money in order to dive what we call vicarious aggression. Put IT simply, people spend an enormous amount of money and time and energy watching other people engage in, for instance, aggressive sports.

And we know that observing your team winning over another team causes the release of neurochemicals in your brain and body that make you feel good. And yes, that can make you feel more aggressive. We also know, of course, that most governments invest many billions, if not trillions, of dollars, in infrastructure, technologies and human beings in order to engage in aggression, if needed, so called military warfare at seta.

So today's discussion will include a description of regression in the pathological sense. Actually, talk about an explosive, aggressive disorder that most of you probably haven't heard of, but is actually far more common than perhaps you. No, we'll talk about the role of things like attention, depth is hybrid activity disorder and how that can relate to aggression through the relationship between impulsivity and aggression.

And we'll talk about verbal aggression, physical aggression, proactive aggression has mentioned before, and reactive aggression. I'm certain that by the end of the episode, you will come away with a much more thorough understanding of what this thing that we call aggression really is. And when you see IT in other people, I think I will make more sense to you.

And when you observe IT in yourself or the impulse to engage in aggression, verbal or physical or otherwise, I hope that you'll understand IT Better as well. And of course, the tools that I will describe should allow you to module and control aggressive tendencies or previous positions, to aggressiveness, and just generally to be able to engage with people in a more adaptive way overall. Before we begin, i'd like to emphasize that this podcast is separate from my teaching and research roles at stanford.

IT is, however, part of my desire and effort to bring zero cost to consumer information about science and science related tools to the general public. In keeping with that theme, i'd like to thank the sponsors of today's podcast. Our first sponsor is athletic Greens. Athletic Greens is in all in one vitamin mineral probiotic c drink.

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That's element t dot com slash huberman and you'll get a free element sample pack with your purchase. They're all delicious. So again, if you want to try element, you can go to element element t docomo slash human. Today's episode is also brought to us by waking up, waking up as a meditation APP that includes hundreds of meditation programs, mindfulness trainings, yoga eda sessions and nsd r non sleep depressed protocols.

I started using the waking up up a few years ago because even though i've been doing regular meditation since my teens and I started doing yoga ea about a decade ago, my dad mentioned to me that he had found an APP, turned out to be the waking up APP, which could teach you meditations of different durations. And that had a lot of different types of meditations to place the bringing body into different states, and that he liked IT very much. So I gave the waking up up a try, and I too found IT to be extremely useful, because sometimes I only have few minutes to meditate.

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I think that many people out there are put off by aggression, although others are drawn to aggression both in themselves and when observing IT in others. The reason to talk about aggression is that, as mention before, the context of aggression really matters. So there are instances where aggression is adaptive.

For instance, a mother protecting her children if she's being attacked or her children are being threatened. I think most people would agree that so called maternal aggression of that sort, provided the context is right, is a great thing. Protecting our Young is, after all, one of the primary adaptive drives of our species.

And think gunness IT is, of course, other forms of aggression, like unprovoked, pro active aggression, somebody simply being violent to somebody else, even when unprovoked. Most of us cranes, when we see that kind of behaviour, we can even evoke aggression in people when they observe that kind of behavior. So again, context really matters.

But a more general, and perhaps in more important reason to think about and understand aggression is that by understanding the biology and psychotic of aggression, you will be in a much Better position to understand how all emotional states come to be, both in yourself and in others. For instance, many of you have probably heard the statement that I believe arises from pop psychology, not from formal academic psychology, that aggression is just sadness. It's a form of sadness that's amplified and IT shows up as aggression.

But when we look at the underlying biology and the peer reviews literature on this, nothing could be further from the truth. We have distinct circuits in the brain for aggression versus grief and morning. Those are non overlapping. Now that doesn't mean that you can't be sad and aggressive or in a state of morning and aggressive at the same time, but the idea that sadness and aggression are one in the same thing is simply not true.

And by understanding that, or perhaps by understanding that irritability and aggression are not the same thing, you'll be a much Better position to apply some of the tools that we will talk about in this episode in order to be able to reduce or eliminate or if it's adaptive to you to moderate aggression. And yes, there are cases were modulating your aggression, in some cases, even ample flying aggressions can be adaptive. Now this, of course, is not the first discussion about the biology of aggression, where the psychology regression.

And we really can look to the beginning of the last century, at the time in which the formal study of aggression really began. One of the names that most associated with the formal study of aggression is none other than cona larens. Some of you may be familiar with that name, others of you may not be familiar with that name. Cradle's studied so called in printing behaviors and fixed action pattern behaviors. He's most famous, at least in scientific circles, for getting geese to believe that he was their parent.

And if you were to put into google conrad with A K larens, just as IT sounds, conrad geese, you're going to see a lot of photos of conrad walking down roads with a lot of geese following him, or swimming lakes with a lot of east following him, yet a habit of geese adopting him because of the behaviors that he partaken. So he would swim out on a lake in front of a bunch of logic, and then they would think that he was the parent, and they would imprint on him. He even lived with these animals, and they lived with him.

A strange character, from what I hear, but none. There's all. This work was deserving a of a nobel prize, because what he discovered were fixed action patterns, that is, patterns of behavior that could be evoked by a single stimulus.

Okay, this is really important. The idea that you can get a whole category of behaviors like swimming behind a parent or looking to somebody for comfort and only them. The idea that that you could get a huge category of different behaviors in a bunch of different context, triggered red by just the presence of that person is remarkable.

Because what is suggested in what turns out to be true is that there are neural circuits, not just individual brain aries, but collections of brain areas that work together to engage a pattern of behaviors. And that's the first fundamental principle that we need to define today, that when we talk about aggression, we are talking about activation of neural circuits, not individual brain, is but neural circuits. They get played out in sequence like he's on a piano, but that playing out in sequence means that aggression is a verb that has a beginning, a middle and an end.

And it's a process, it's not an event. And as you'll see, that turns out to be very important in terms of thinking about how one can halt aggression, prevent that from happening before it's initiated or maybe in prolonging aggression, if that's what's needed. Now conrad's had no real knowledge of neuroscience IT.

I mean, obviously, he knew there was a thing that we call a brain and the nervous system, and he knew that there were chemicals in the brain and hormones and things that sort that we're likely to play a role. But he really didn't take any measures to define what the neural circuits were, Frankly, didn't need to. He had his nobel prize, and he did all this beautiful work, known for an abundance of work.

But he did think about what sorts of underlying processes could drive something like aggression. And he talked about one particular feature that's especially important. And that's this notion of a pressure, the idea that, yes, certain hormones will bias somebody or an animal to be aggressive.

Certain transmit states, and you'll learn with those are today, will buy us somebody to be more or less aggressive, maybe even submissive and passive, maybe out right, proactively aggressive towards anyone or anything in front of them. And yes, of course, there will be historical features based on their childhood at a he understood that there will be a conStellation of things that would drive people to be aggressive. And he described as so called pressure, almost like a hydraulic pressure.

Just think about fluid pressure in a small container. Push, push, pushing until the can or the container is ready to explode, and how multiple features, multiple variables could in pinch on that and create that pressure. And turns out that's exactly the way that system works. There is no single brain area that flips the switch for aggression.

Although we'll soon talk about a brain structure that generally houses the propensity and the output of aggression, this notion of a hydraulic pressure that can drive us toward aggressive behavior, or conversely, can be very low pressure and keep us in the state of nonreactivity, maybe even even passivity or submissiveness, is a very important feature, because IT really captures the essence of how neural circuits work when we're talking about primitive behaviors generally. And you can start to notice this in yourself and in others. You can start to notice when you are wearing toward aggression or when someone is wearing toward aggression, verbal or physical, now that waring is the build up of this hydroid pressure that the rends was referring to.

And IT really does have an underlying biological basis. Now, IT was some years later that the first experiments came along, which really started to identify the brain areas and the biological so called pressures that can induce aggressive behavior. And the person that really gets credit for this is a guy by the name of walter hess, who at that time was working on cats.

And I know that when, say, working on cats, a lot of people who crank, a lot of people who have cats as pets, and certainly cats can be delightful. Some people like them more, or some people like them less. Most people printed the idea of doing experiments on cats.

I should say that these days, very few laboratories work on cats. Most laboratories that work on animal models will work on flies or software, fruit flies for their capacity, due genetics on laboratories, mice, sometimes rats, but usually mice. And occasionally you'll find a lab that still works on cats back in the time of has very few laboratories worked on mice.

Most laboratories worked on cats or rats. And the reason for that is nowa ys, most laboratories use mice if they use animal models, because of the genetic tools that existed. Me to knock out this team, or knock in this in that said, a, which can be done in humans or non human primates, at least not very easily at this point in history.

So when I say he was working on cats and realized that probably evoke some negative emotions in some of you, may be even aggression in some of you, what we can do, however, is look at the data and make use of the data in terms of our understanding. What has did was he had cats that were awake, and he was able to lower stimulating electrode into the brain. Now keep in mind that the brain does not have any pain sensors.

So after a small hole is made in the skull, electrics alert into the brain. This is what's done commonly in human ero surgery. And he was able to stimulate different brain areas, and he was sort of poking around.

And when I say sort of, he was doing this with some logical intent and purpose, he wasn't just poking around and there for fun. He was trying to identify brain regions that could generate entire categories of behavior. Allah larens, right? These fixed action pattern behaviors.

Eventually, his electrode landed in a site, and he provided electrical stimulation to the cat that cause this otherwise passive pouring, relaxing your cat to suddenly go into an absolute rage. So arched back, hissing hair up, so called pilot direction, where the hair go up. Animals try to make themselves as big as possible, often when they are aggressive, dreaming, maybe even been spitting, believing not cats and other animals can do this.

And the cat tried to attack him and anyone else, and anything else, even in the animal objects, when he stimulated particular brain area. So has obviously took notice of this incredible transformation in behavior and the fact when he turned off the stimulation of this particular brain area, the cat, very quickly within seconds, went back to being passive com Kitty. Now, of course, he repeated this experiment in other animals because he had to confirm that IT wasn't just happened to that.

There wasn't something unique about this one cat that perhaps he had stimulated an area that had been built up during the kitten hood of this a of this cat, and had been reactivated. Maybe this kitten had been traumatized early in life, or scared and reactivation of a particular circuit unique to that, cat created this aggressive behavior. That wasn't the case.

Every cat that he looked at and stimulate this particular brain area, the cat would immediately go into an aggressive, almost rage type behavior. Of course, we can't enter promotional es. We don't know what the cat was feeling for all we know, the cat could be happy, although that seems pretty unlikely.

And later, experiments done in mice, but also in humans, confirm that, indeed, stimulation of this brain area evoke not just behavioral aggression, but also subjective feelings of aggression and anger. So what was this incredible brain area, or rather, I should say, what is the brain area that harvard, this incredible capacity to generate aggressive behavior in his his experiments? Well, for those of you that are regular listeners of this podcast, you will probably be relieved to know that today we are going to talk about some new neural circuits times we'll ll center back on the a migdalia or the profondo cortex in those names will come up.

And for those of you that haven't heard them before, don't worry, all make IT clear as to what those brainers are and what they do. But today we're going to talk a lot about the so called V M H, or venture al media hypothalamus. The venture your, this is a nucleus, meaning a small collection of neurons.

What are neurons? Nerve cells? And that small collection of neurons that we call the venture medio hypothenuse, is truly small, is only about one thousand five hundred neurons on one side your brain, and a matching one thousand five hundred neons on the other side of your brain.

And that combine three thousand neons or so, exactly thousand, but three thousand neurons or so is sufficient to generate aggressive behavior of the sort that has observe in the cat and believe IT or not, when you see somebody who's in the act of rage, or an act of verbal aggression, or in an active defensive aggression, protecting their family or loved ones or country. Etta, almost certainly those neurons are engaged in that behaviour. Those neurons are perhaps even generating that behavior.

Next, all describes some experiments that we're done just recently within the last ten years or so, but leading right up until this year and even last month that keep confirming again and again and again that IT is the activity of neurons in the venture media. Hypothalamic are both necessary and sufficient to generate the full catalogue of aggressive behaviors. Now before I go further to describe the beautiful recent studies on the v mh, the venture media hypothesis and the important role of testosterone and more importantly, estrogen in the activation of aggressive behavior.

That's right. That's soon to be clear to you why that's the case. I want to emphasize that the ventral media hypothalamus is something that we should all care about. why? Well, IT turns out that many categories of psychiatric disorders, developmental disorders and psychological chAllenges, things like schizophrenia, a ptsd, postal matic stress disorder, depression, borderline personality disorder and even certain forms of autism, can include elements of aggression and even violence.

Now is certainly not the case that aggression and violence are present in all people who suffer from is a french or ptsd, or depression or autism or borderline personality disorder. Absolutely not saying that, however, IT can be a feature of those and it's a well described feature. In terms of trying to to understand the conStellation of chAllenges that people suffer from when they have though.

So thinking about the v mh goes way beyond just understanding basic aggression in the context of adaptive aggression. So you know, when a earlier, I use example, maternal aggression, that's one adaptive form of aggression, IT also can be pathologic aggression, and I can harm ourselves or others. So keep this in mind as we go forward to, because later were going to talk about specific tools designed to modulate or prevent aggression in for instant people with attention deficit hyperactivity disorder and especially kids with add.

In the meantime, let's return to the vm h. This relatively small collection of neurons. And the reason I say relatively small as well, your brain has many hundreds of billions of neurons, maybe even trillions of neurons.

Exact number of neurons doesn't really clear, but it's a lot and IT certainly is a lot relative to the number of neurons, this three thousand or so neurons living in your hypothalamus that can evoke this aggressive response experiments done by David Anderson's lab at cal tech. We're really the first to pass the fine circuitry and to really show that the venture media hypothalamus is both necessary and sufficient for aggressive behavior. These are important experiments in their worth.

Knowing about what they did was they identified, first of all, where the venture media pathna as was in the mouse, that was pretty raght forward to do a sort of known before they started these experiments. And then they analyzed which genes, meaning which D N A, which of course, becomes R N A, and R N A becomes protein, which DNA, and therefore which proteins are expressed in particular cells of the venture, my hypothalamus. And IT turns out that there is a particular category of neurons in the venture media, hypothalamus that make an estrogen receptor.

And IT is those neurons in particular, that are responsible for generating aggressive behavior. How do they know this? Well, they used a tool that actually been destroyed by a previous guest of this podcast.

We had an episode with a psychiatrist, bioengineer and my colleague, stanford school medicine coral draw. He and others have developed tools that allow people to control the activity of neurons, essentially by remote control, by shining light on those neon. So in the context of an experiment on a mouse, which is what David slapped did.

And these were the beautiful experiments of dyin, who's now in her own laboratory at new york university, put a little fiber optic cable down into the brain of the hype, the hypothesis, that is, of the mouse. The mouse is able to move around in its cage, freely moving even. That has a little tedder.

This little wires are very thin wire. And that little thin wires, actually, what we call up trode. And the experimental alist, in this case die, was able to stimulate the turning on of a little bit of blue light.

And that blue light activated only those estrogen receptor neuron in only the venture media hypothalamus. And the way he was able do that, as he had to introduced a gene that have been developed by our friend, carl, that allows light to trigger electrical activity of those neurons. So if any of that is confusing, or all of that is confusing, here's the experiment.

There's a mouse in a cage as little wire coming out of its said, IT doesn't notice. Believe IT or not, we know this because it's still eating and made in doing all the things that might like to do on daily basis and sleeping at seta. And the mere presence of a button will activate a little bit of light released at the end of that wire that light activates.

Particularly neons, in this case, is the estrogen receptive containing neurons in only the venture media hythe's. When that mouse is in a cage with another mouse, a couple of things happen depending on what the other mouse is. Or we could say who the other mouse, if it's a male mouse, and you put in there with a fee male mouse, the male mouse will attempt to mate with a female mouse.

Provided that the male mouths has gone through puberty, he will try to mount and make with a female mouse. Now, female ice are either in a receptive phase or a non recept of phase that there's called extra cycle. They don't have a menstrual twenty eight day cycle that even extra cycle.

And on particularly days at that extra cycle, they are not happy to met. They will basically keep their high quarters away from the male mouse at all costs. They'll even attacked the male mouse on certain days of the extra cycle. However, the female mouths will undergo what's called lord is, which is an arching of her back, and you'll allow the mail to mount and mate with her so large number of experiments were done, but the first experiment really was to put the male mouse in with a female mouse whose, in the so called receptive phase of astra, that is, he will allow, and he starts mating with her.

And they go through the standard repeat are of mating behaviors that you observe in mice mounting thrusting information is its called in the mouse sex world I guess I don't know what the mice call, but that's what the experimenters call IT and then afterwards that he will disband. okay? So they observe this kind of mounting in, and sex behavior is very typical, but about halfway through the behavior that you turned on the light to stimulate the estrogen recept container on only in the male mouse.

And what he observed was incredibly dramatic. The male mouse ceases from trying to mate with the female mouse and immediately tried to kill the female mouse. He starts attacking her.

Then he turns off the light. The male stops and goes back to trying to meet with the female else. I'm sure all of this was very confusing and disturbing to the female male.

Nonetheless, that was the repeat they would meet. You would stimulate these venture, medio hypothalamic neurons. The male mouse would immediately trying to attack and kill the female mouse, and then SHE would stop the stimulation, and he would stop trying to attack and kill the female mouse.

Return to the attempt, at least to mate with the female mouse. These are such dramatic shifts in behavior triggered only by the activation of only the small set of neurons within the venture media hypothetic. And for those of you that think that you can watch the sort of thing without being disturbed, I encourage you to go to youtube.

We will provide a link, uh, where you can see a video of this type of behavior. It's incredibly dramatic. The shift in behavior is almost instantaneous. Curse within seconds, if not more seconds, thousands of a second. The next experiment that he did was to put a male mouse with this stimulation with light capability in its venture.

Media hysteria is into a cage alone, but with a rubber glove filled with arrow water mouse walking around sniffing ping, which is what male mice seem to do. They seem m to hurn ate everywhere as actually an interesting, perhaps interesting, future of male mice and action. Many male animals, perhaps even humans, we don't know, or maybe we do know.

Basically, this has been the observe time and time again in experiments, mainly by lisa towers lab at the script institute, is characterize this, if you put female mice into an arena, a cage, they always, year in eight, in a very small corner of that cage, where, as if you put male ice into an arena or a cage, that you're and me everywhere, they have this kind of session with springing that you're in everywhere you can um sort of transport SE that to human behaviour, if you like, in any event that you put the mouse in the cage alone. But with this rubber glove the mouse is walking around, you're ending eeta doing whatever is that my do then SHE stimulate tes the activation of these venture medio yp themes neurons. And the mouse immediately tries to kill the glove.

IT goes into a rage, attacking the glove as if IT were another mouse or some other animate object. But of course, it's an inanimate object, is just a rubber glove. SHE stops the stimulation, and the mouse immediately goes back to being completely calm, or at least not attacking.

Again, we don't know what the mouse was feeling. So these are very dramatic videos. Again, you can see them by following the links that we will provide in the caption if that sort of thing is going to disturb you by a to see fern since the attack, one mouths attacked and please just don't watch them.

I'm not interesting um traumatizing anybody or you traumatizing yourself. That is A A number of different variations were done on this experiment. For instance, stimulating the vm h in female mice as a post male mice, the female mice in with other fema mice or with other male mice, no matter what variation one Carries out.

So IT doesn't matter if it's male with female, male with male, female, female eta stimulation of the venture media hypothalamic, a male mouse or female mouse evokes there's a very dramatic, almost instantaneous aggressive behavior, physically aggressive behavior. Subsequent experiments done by dyin in her own laboratory and other laboratories have shown that the venture media hype athamas is connected with a bunch of other brain areas that are interesting. And i'll talk about some of those in a little bit, but one of them that I want to call out now is the so called P.

A G, the paradoxical grey nucleus. This is a large structure in the back of the brain that how's things like neurons that can create ops. We all know if the opp o crisis, but these are neons that can produce industrious means made by the body, chemicals that can cause pain relief.

You can understand why that might occur in a circuit for aggression, right? Even if one is the aggressor, it's likely that they may incur some physical damage and you'd want some pain relief. The P. A G also is connected to a number of neural circuits that eventually, through several processing stations, stations, excuse me, arrive at things like the jaws and in fact, stimulation of the venture menu hypothenuse can evoke biting and aggressive biting behavior.

Now, aggressive biting behavior is particularly interesting, because in humans, and especially in human children, biting is something that, while Young children might do as a form of aggression, tends to disappear pretty early in childhood. And if IT doesn't, it's often seen as a mark of pathology. I have a story about this actually when I was a kid I went to a summer sports camp and I i'll never forget this that we are playing soccer and um in a in a rare stroke of locker accident happened to score goal.

I wasn't a particularly good socket player, especially not at that stage of my life. They later figured out that I was just Better to make me a full back because I could just wait there and do what full backs to do as Better taking the ball or the person out. Then I was putting the ball in um the goal none's I again by chance I.

Score to go. And I was trotted back to my side of the field and all the sun. I felt this thing in my back.

A kid not to be named. I do remember your name. I'm gonna tell you what his name was. A kid jumped on my back and bit me on the top of my back. And this, of course, resulted in a discussion, and in a time out, in all the usual things and parents, I think god involved.

I don't recall anything much else of IT, but I recall that this was considered especially troubling behavior because he bit me as supposed to hit me or shoved me down, or something that sort. And IT does seem as if the tendency to use biting as an aggressive behavior is associated with a more primitive circuitry. Now here i'm truly antiproton fied.

I don't know what this other kid have to be thinking or feeling at the time. How could I and I certainly am not going to say that biting in every case reflects a pathology. Although I think there is general agreement in the psychology community, in the psychiatric community, that past a certain age, the using of one's teeth to impart aggression, gresh and damage on others is that particularly primitive and troubling? At least for the observer, the person experiences a pretty disturbing event.

Diese lab has shown that activation of the ventures media of hypothermia triggers the downstream circuit in the paraquat cal gray, which then triggering a whole other set of circuits of fixed action patterns. Here we are, bachelor reza N. S. With fixed action patterns, including swinging of the limbs, right punching. This wouldn't necessarily be controlled punching, but also biting behavior.

So it's remarkable to me at least, that we have circuits in our brain that can evoke violent use of things like our mouth or violent use of things like our limbs that, of course, could be used for things like singing or kissing or eating or, you know, just speculating in any kind of polite or in polite way. The point here is that neural circuits, not individual brain areas, evoke the conStellation of behaviors that we call aggression. Now, many of you are probably puzzled, or at least should be, because i've been talking about this highly specialized brain area, the venture media hypanis is, and this highly specialized subcategory of neurons in the venture media hythe's these neurons that make estrogen.

And yet the activation of those cells triggers dramatic and immediate aggression, both in males and in females, and both against males and against females. What's going on here? Most of us think about estrogen, and we don't immediately think of aggression. Most of us here testosterone, and we might think about aggression, although other things as well. In order to understand this, I just want to briefly refer back to a conversation that I had on a previous episode of the human lab podcast, and that was with my colleague, the great robberts.

A post key, of course, is a professor stanford studied to stop one and its impacts on behavior, as well as astrogation and hormones, their impacts on behavior, to make a long story short, and to dispell a still unfortunately, very common myth. Testosterone does not increase aggressiveness. Testosterone increases pro activity and the willingness to lean into effort in competitive scenarios.

Sometimes this is referred to as the chAllenge hypothesis. But to make a long story short, if people are given testosterone, or if you look at people who have different levels, excuse me, of testosterone dorgan's that they naturally make, what you'll find is that testosterone tends to increase competitiveness, but not just in aggressive scenarios. So if somebody is already aggressive, giving them testosterone will have the tendency to make them more aggressive.

If somebody, however, is very benevent, lent and altruistic, giving them to ostern will make them more benevent, lent and altruistic, at least up to a point. Now, of course, there are are certain forms of synthetic testosterone es that are known in sports circles and in other circles to increase aggressiveness because of the way those particular forms of sthetic test astronauts work. But in general, most of the experiments that are referred to have not been done using those that have done using the, let's call them, the more traditional biological forms of testosterone, or that resemble the biological forms of distinct Robert suppose.

He described a really interesting experiment in which, if you look at the stock levels, or you administer additional test, test to people who are doing philanthropy, giving money to organizations, they essentially doing good, because these are organizations doing good. What you find is that increasing testosterone, or further increasing testosterone, one makes people more willing to compete to give more money than the other person in the room, in order to put IT in air quotes to alpha out the other person by giving more money. So this is an act of altruistic or benevolent philanthropy.

IT is not act of aggression. Of course, we don't know what the people are feeling underneath all that. Again, we can't enter promotional es or project on other people what they are feeling.

But the point is that testa tron itself does not make people more aggressive. And in the experiment that we've been talking about up until now, it's actually the activation of estrogen receptor containing irons that makes these animals more aggressive. And IT turns out there's evidence that in certain context, estrogen can make people more aggressive.

So what's going on here, what's going on is that testosterone can be converted into estrogen through a process called a robotization. There's an ensign called a rotate. Any time you have word, the ends in A S E, at least if fits in the context of biology, it's almost always, not always, but almost always an so the aroma zone converts testosterone into estrogen.

And IT is actually testosterone, aromatic zed, converted into estrogen and then binding to these estrogen containing neurons in the venture media hypothalamus. That triggers aggression. I want to repeat that IT is not testosterone on itself that trigger aggression. IT is testosterone, aromatic zed, into estrogen within the brain and binding to these estrogen receptor containing irons in the venture media hypothalamus that evokes aggression and dramatic aggression at that.

Now, this effect of estrogen causing aggression in the brain is very robust, so much so that if you take a mouse that lacks the romantic enzi, or a human that lacks the romantic and time, and they do, then there is a reduction in overall aggression despite high levels of testosterone. And if people who, or mice who have the roman enzyme have that enzyme blocked, well, then IT doesn't matter how much you increase test astre one or any of its other derivatives, you do not observe this aggression. So this runs counter to everything that we know.

And think about the role of testosterone. Again, testosterone increases competitiveness. IT can increase the desire to work under chAllenge. I've said IT before, and I ran this or pressure tested this against Robert suppose sky, who's been working on testosterone and its role in the brain and behavior for many decades now.

IT is fair to say that testosterone has the net effect of making effort feel good, or at least increasing the threshold at which effort feels bad or unsustainable. And IT does that by way of changing the activity or the thresh hold for activation of brain structures like the amiga la and other brain structures associated with anxiety. So the next time somebody says testosterone makes people aggressive, you can say, ah no, actually it's estrogen that makes people aggressive and animals aggressive for that matter.

Now of course, IT is the case that because males have relatively less estrogen circulating in their brain and body than females, right? Because the test is not over, that testosterone is required in the first place in order to be converted into estimate to activate this aggressive circuit involving these estrogen receptive containing neurons in the venture media hypothalamus, but nonetheless is estrogen. That is the final step.

IT is the hormone on which aggression hinges. And I think for most people, that's a quite surprising finding. And yet, this is perhaps one of the more robust findings in both the animal and human literature.

As IT relates to hormones and psychological states and behavior course, IT is the case that if testosterone is low, that a person or an animal will exhibit less aggressive behavior. But that's not because of reduced testosterone persae. It's because of the subsequent reduction in testosterone.

Meaning if there's no testosterone to error, tize into an estrogen will also be lower. So we've establish that it's not testosterone, but testosterone converted into estrogen that activates the circuits for aggression. But nonetheless, it's still surprising, right? I mean, most of us don't think about a estrogen as the hormone that stimulates aggression IT. Turns out it's all contextual.

There are beautiful data showing that whether or not estrogen stimulate aggression can be powerfully modulated by whether not days are short or days are long, in other words, whether or not there's a lot of sunshine or not. Now obviously, brain is in case in skull, so IT doesn't really know if there's a lot of sunshine out, even though you can see the sun with your eyes, you can feel IT on your skin. Dayle th is converted into hormonal signals and chemical signals.

And the primary hormonal and chemical signals involve melatonin and doping, and also the stress warmth. And to make a very long story short, in the long days where we get a lot of sunlight, both in our eyes and on our skin, melatonin levels are reached. Military is a hormone on that tends to produce states of sleepiness and quiescence.

IT also tends to activate pathways that tend to reduce the things like breeding and sexual behavior. In long days, dopamine is increased. Doping is a molecule associated with feelings of well being and motivation, and the desire to seek out all sorts of things, all sorts of motivated behaviors.

And in long days, provided we're getting enough sunlight on our skin and to our eyes, the stress for mones, especially court, as all and some of the other stress hormones are reduced in levels if estrogen levels are increased experimentally under long day conditions, IT does not evoke gassion. However, in short days, if estrogen is increased, there is a heightened previous position for aggression. And that makes perfect sense.

If you think about what short days do to the biology of your brain and body. In short days, the military and signal goes up. There's more military and circulating for more of each twenty four hour cycle.

Stress hormones are circulating more. Why short days tend to be associated with winter? In winter, we are bombarded with more bacteria, viruses.

Because bacteria, viruses actually survive Better in cold than they do in heat. In fact, in my laboratory, we work with a lot of viruses and bacteria. When we want to keep them alive, we put them in the freezer.

If we want to kill them, if we want to accuse ate them, we put the other U. V, light, like you to see from the sunlight. So shorter days are conducive to aggression, not because they are short per, but because stress, formal levels are higher and because dopamine levels are lower. Now here's where all of this starts converge on a very clear biological picture, a very clear psychological picture, and indeed, a very clear set of tools that we can think about and use. Under conditions where court is all is high, where the stress hormone is elevated, and under conditions where the neuromodulator serotonin is reduced, there is a greater propensity for estrogen to trigger aggression.

Now again, I know i've said IT before, but for males who make a lot of testosterone on relative estrogen, you have to swap in your mind this idea that if testosterone is high, that means that s rogen is low, because, well, that can be true in the periphery y in the body. If testosterone is high, there is going to be some of romanization that conversion of teston ergen. So any time you hear that testosterone is high, you should think testoon is high in the body and perhaps estrogen is low in the body.

But that means there's going to be heighten levels of emerging in the brain and therefore increased propensity for aggression. In females who generally make less test astern relative to estrogen, there is sufficient emergent already present to trigger aggression. So both males and females are primed for aggression.

But that's writing on a context. And that context of whether not you get a tendency for aggression or not depends on whether not cortile is high or low. And i'm telling you that if cortisol is relatively higher in any individual, there is going to be a tilt, an increasing that hydraulic pressure that larenz talked about toward aggression. And if serotonin, the neuromodulator that is associated with feelings of well being, and sometimes even a slight possibility, but certainly of well being, if serotonin is low, there's also gonna a further shift towards an aggressive tendency.

So if we return to Lorenz hydro lic pressure model of aggression in other internal states, we realized that external al stimulus, things that we hear, things that we see, for instance, someone saying something upsetting or are seeing somebody do something that we don't like to others or to us, as well as our internal state, our subjective feelings of well being, but also our stress level, our feelings of whether not we have enough resources and our content with what we have. All of that is converging on this thing that we call internal state in creating this pressure of either to be more aggressive or less aggressive. And now we have some major players feeding into that final pathway.

That question of whether not will we hit the other person? Will we say the thing that is considered aggressive, but we not say that? If somebody says something or does something aggressive to us, will we respond? Or will we be submaster ve or even passive again?

There are many things falling into that question in dictating whether not the answer is absolutely all, fight back or i'm going to attack them even unprovoked. Or if they say that i'm going to do that, or no matter what they do, i'm not going to respond. These kinds of things are very complex, and yet we really can boil them down to just a few common elements. And i'm telling you that those elements are, whether not cortisol levels are relatively lower or relatively higher. Again, relatively higher is going to tend to make people more reactive.

why? Because reactivity is really a function of the autonomic nervous system, which is sort like a sea saw that isolates between the so called sympathetic ARM of the automated ic ary system, which tends to put us into a state of readiness through the release of a drennen court, is all in a journey when they are circulating, the brain and body, make us more likely to move into react, and to speak, it's actually what will induce a kind of low level tremor, which is an anticipatory trauma, to be able to move more quickly, right? Body in motion is more easily set into further motion, that is, and the ne modulator serotonin is a nurse dulce.

Or that in general, is associated with feelings of well being in response to what we already have. So when we are well fed, sir tone intends to be releasing our anybody in particular welfare with carbo hydrates. The precursor to serotonin is trip to fan.

And indeed, there are nice studies expLoring the types of diets, nutritional programs that can reduce aggression behavior, both in children and in adults, and trip to fan rich diets or supplementation with trip to fan. So for trip to fan rich diet, things like White turkey meat, but then they're also a number of over hydrates. You can look up.

It's very easy to find foods that contain lots of trip to find those foods contained the precursor to settle. And now IT isn't simply the case that eating more foods with trip to fan will tend to reduce your aggression as well as they could do that. If you ate IT in abundance, IT could make you tired and then you're less likely to be aggressive.

I don't recommend that strategy, but the idea here is that when it's been explored, increasing levels of trip to fan, either by supplementation or by food or drugs, prescription drugs that increase serotonin offer in its flu oxyde, sometimes called prose acs, or after any number of the other assessors, tend to reduce aggressive behavior. Now, not always, but in general, that's the case. Similarly, because elevated cortisol tends to shift the whole system again, create more of a hydro lic pressure towards aggressive states.

If courses all levels are reduced, well, then the tendency for aggressive behavior is reduced. This is supported by a number of peer reviewed studies, will provide links to some of those in the caption showing te. We're going to return to this a bit later in the context of specific studies that have looked at genetic variants in different individuals that caused them to make more or less serotonin, or at least to meet ability serotonin differently.

This is also the case for so called the intervention explosive disorder that can often be associated with gene variants that control how much serotonin is made or how it's metabolize or how much court is made and how much is metabolic in thinking about tools, there are number of things that one could consider. First of all, there are number of decent studies expLoring how supplementation with the omega three fatty assets, which are precursors of some of the transmitter or systems, including seattle, in that can modulate not directly mediate but modulate mood and emotional tone. Supplementation with the omega trees has been shown to reduce impulsivity and aggressively in certain context in things like A D, H, D, or in individuals who have a pre disposition for aggressive, tight behavior or aggressive thinking.

Now that doesn't necessarily mean that the omega fatty assets are going directly to the venture media hypothalamus changing the activity of neurons there. More likely, they are causing or modulating an overall shift in mood through the immune system, through hormonal systems that are changing the overall tone or the propensity for neurons in the venture al media hypothesis to be activated. How much omega three fatty acid? What source? We have talked about this on the podcast before.

You can, of course, get omega three fatty acid from a number of different foods. Getting them from whole foods is probably the best way to do IT. But many people, including people with depression, will often supplement with one gram or more of omega three fat assets per day.

Some people, including myself, will take them every day as just a general mood enhancer and will suffer from depression. But i've found to be beneficial for my health. And so some people do that. And i've talked about before how, in double blind policy, al control studies people taking one to three grams of omega three fatty acid per day, typically in the form of a high quality. Other, other, other sources as well, L, G and so forth, can experience improvements in mood that are on power with some of the assis, the selected serotonin and reuptake inhibitors.

And of course, if you are prescribed in essy by your psychiatry or doctor, please do take that and don't cease to take IT, just simply to take omega three is, however you might mention to them, and you can find links to the studies in our previous episodes on depression, that supplementation with mega fati assets of, at this one grammar, more of E, P. A, specifically. So getting above that one gram threshold as high as three grams per day of the E P.

A has allowed people to take lower doses of assess, arise and still keep their mood in a place that's beneficial for them and in terms of keep in courtiers all in arrange, that's healthy and doesn't buy a someone told high levels of aggression in your tablet. That's again going to be set by a number of larger modulators of contextual cues. And i've talked about some of those on the pod spital.

Just briefly recap them. Now I will, sly, getting sunlight in your eyes early in the day and as much sunlight as you safely can in your eyes throughout the day is going to be important. Again, because of this effect of stroke en, in long days, not increasing aggression.

However, in shorter days, ater gen increases aggressions because of the increasing cortisol observed in short days. Another way to reduce cortisol was discussing our episode on heat and the use of sona and heat, but also hot bs IT turns out that hot bath and sona can be very beneficial for reducing courters. All all the details on that are included in the epsom on heat.

It's time stamps, so you can go directly to that if you want to learn about the temperatures and the various durations. But you just give a sops is of that a twenty minute sona at anywhere from eighty to a hundred degrees? Sales is going to be beneficial for reducing cortisol.

If you don't have access to a sona, you could do a hot bath, adjust the temperature, sea, don't burn yourself. I think you know, eighty to one hundred degree. So he is going to be too hot.

For many people, it's a hot bath, or as many people hook can't tolerate that. How bad can tolerate the sona? So safety first, always. And of course, but hot bath reduce court as all hot sawn is reduce court as all of a duration about twenty or thirty minutes is going to be beneficial.

And of course, some of you may be interested in expLoring the supplementation round and for reductions in court is all really the chief player there is, uh, uganda, which is known to decrease cortisol fairly potently. I should just warn you that if you're going to use as uganda in order to reduce cortical, first of all, check with your doctor, healthcare provider before adding or attracting anything from your supplementation or health regiment. Of course, I don't just say that to protect us.

I say that to protect you, you are responsible for your health. What you take in, what you don't take, chronic supplementation with ash uganda can have some not so great effects of disruption of other hormonal pathways and or transmitter pathways. So the IT seems to be about two weeks of a regular use before you'd want to take a break of about two weeks.

So uganda, again, a very potent inhibitor of court is all, but with some other effects as well. Don't use IT chronically for longer than two weeks. But if your goal is to reduce court as all, let's say you're going through a period of.

Increase your stability and aggressive tendency. Maybe you're also not getting as much light as you would like. And perhaps also if there are other circumstantial things leading to towards more gressier ess in your goal is to reduce aggressiveness that can be potentially helpful. And in light of all this stuff about cortisol and estrogen and daylight, th should mention that there are, in fact, some people who have a genetic previous position to be more irritable and aggressive and a couple of different gene pathways associated with us. We never like to think about just one gene causing a specific behavior.

The way to think about genes is that genes generally code for things within our biology in the context of days discussion, things like neural circuits, or the amount of neurotransmitters ors that are made, or the amount of hormones that are made, or the amount of neurotransmitter or hormones, receptors or enzymes that shift the activity of our biology in a particular direction. They bias our biology. And in fact, there is a genetic variant present in certain people that adjust their estrogen reception sensitivity, and that extradition receptor sensitivity can result in increased levels of aggression, sometimes dramatic, and increases.

However, and also very interestingly, photo period, meaning daylight, is a strong modulator of whether not that aggressive veness turns up or not, whether or not that person with the particular gene variant is more aggressive or not, depends on how long the day is and how long the night is. One particular study that I like that references, this is trainer at all. The title's study is photo period reverses the effects of emergence on male aggression via genomic and non genomic pathways.

This was a paper publishing the proceeds of the national academy of sciences will put a reference to this in the shown that if you would like to explore further. But IT really points to the fact that rarely, sometimes, but rarely, is in the case that just one gene will cause somebody to be hyper aggressive, almost always there is going to be interplay between genetics and environment. And as environment changes, such as day leave changes and the link of night changes, so too will the tendency for people with a given genetic variant to be more aggressive or not.

Now, of course, in the absence of detailed genetic testing for this particular estrogen recept variant, most people i'm missing you are pulling, not walking around knowing that you have this gene or not. Regardless, I think it's important to pay attention to how you feel at different times of year, depending on where the night, summer, whether not the winter, whether you're getting sufficient sunlight, meaning viewing sufficient sunlight or not, whether not you're getting sufficient sunlight exposure to your skin or not, whether or not your indoors all the time, generally, those things create with season, but not always. You can go through long bouts of you're hard work in the summer months when days are long, but you're indoors a lot and getting a lot of flowers in light exposure late in the evening.

And perhaps that's when you're feeling more aggressive. So we have to be careful about drawing a one to one relationship between any biological feature and certainly psychological or behavioral feature like aggressiveness. But it's, I believe, helpful to know that these genetic biases exist, how they play out again.

They shift our biology in in a general, they're tic direction. They don't change one thing. They change a variety of things that bias us todder away from certain psychological and behavioral outcomes and the very thing that we can do in order to offset them.

And we describe those earlier in terms of trying to keep court as allow by getting sufficient sunlight regardless of time of year and regardless whether not you happen to have this particular genetic variant. So earlier I talk about how IT is testosterone converted into estrogen that's activating aggression in the venture media hypothalamus, not testosterone itself. However, there awesome studies Carried out in humans that have evaluated the effects of testosterone and how levels of testosterone corporate with aggressiveness in the short term.

Just going to detail a few of those studies because I think they are interesting and important. First of all, there is a study that has explored levels of testosterone in men of different professions. Now before I tell you the data, I want to be very clear here with the studies such as this one never knows whether or not these men went into a particular profession because they had a testosterone level of a given value, or whether not the work itself altered their test astern levels or both.

And I think it's fair to assume that that it's probably both. So be very careful in assuming that a given test astern level is causing for choosing a particular career or that a particular career is causing for creating a particular testosterone level. This study used celia testosterone levels as the measure, which, to be fair, is not the best way to measure testoon.

Typically, blood raw would be the best way to measure testosterone, provided the appropriate methods are used cel very testosterone one can be a reasonable measure of testosterone. The different occupations that were looked at were, and here they just looked at men in this particular study where ministers, salesmen, they didn't say what particular types of salesmen, fireman, professors of all things, physicians and nfl players. And what they discovered was that the testosterone levels were essentially in that order, from low to highest.

So minister, salesmen, fireman, professor, physician, nfl player, now we could microdissection all the different stereotypes and all the different features of each of these jobs. For instance, we don't know whether or not the fact that the fireman happened, at least in this study, to have lower tester levels on average, then the professors of the physicians was because firemen have lower testosterone n levels, or because they have a much more stressful job in the courtezan. L levels are higher, then the professor, the physician and cortile.

And testosterone, not always, but generally are in so what tagish push poll mode because they derive from the same precursor, typically when when court is all as high to also intends be lower and vice versa. So we don't know what's causing these effects. And again, this is just one study and just six occupations, but I think it's relatively interesting given the fact that each of these professionals involves different levels of competitiveness, right? So we don't necessarily just want to think about the level of physical exertion that's required, but also the level of competition ess, because it's known that competitive interactions can cause increases in testosterone, in particular in the winners of competitive interactions.

A topic for a future podcast. Meanwhile, studies that have analyzed also, again, st celebrated astern in prisoners, in this case female prisoners. So these are incarcerated individuals have looked at levels of test, also one according to whether or not the person committed a non violent or a violent crime in order to arrive in prison at higher levels of celebrities, also were related to those that had arrived in prison because of conviction of a violent crime as a poster.

Non violent crime, likewise, when they analyzed prison rule violations, so an indirect measure of aggressiveness, but in this case, IT was strongly associated aggressively because they knew with the violations were, they found were for prisoners that had none, no prison violations, prison rural violations. I say their testosterone one levels tended to be lower than the testosterone levels of women that had some, even one or more aggressive violations of prison rules. We will provide links to these studies in the shower notes, if you like, to go into them further.

Obviously, studies like this need to be taken with a grain of salt, because there are so many different factors. Different prisons have different degrees of, uh, you know, violence to begin with and competitiveness to begin with. But just as a final pass at examining the role between testosterone and aggressiveness, there was a very interesting study from god at all G O E T Z publishing, two thousand and fourteen that looked at serious, so in this case, blood levels of testosterone, thirty minutes after application of a jail based tester on the ghost train geral, so the testosterone can go very quickly into the bloodstream.

And then did brain imaging to evaluate the activity of neons in the so called critical media ami gala, the ticket, the media madelia is one of the areas of the amiga. A complex as we call IT, because it's complex is got a lot of different nuclei of, you know know what, nuclear are low clusters. It's got a lot of different ones.

But that media, and that critical media, middle in particular, is known to be associated with aggressive type behaviors. IT linked up with is part of the larger circuit that includes the venture media hypothesi us. Another brain area is that we refer to earlier, such as the pag.

What is remarkable about this studies that showed that just thirty minutes after application of this so called android jail, this testosterone that seeps into the bloodstream, there was a significant increase in, of course, testosterone and dial media, a meal activation. So test astro can have acute effects, immediate effects on the pathways related to aggression. And I think this is something that's not often discussed because many of the effects of steroid hormones like testosterone astern are very slow acting.

In fact, story hormones, because they have a certain biochemical composition, can actually pass through the membranes of cells so the outside of a cell and into the nucleus of the cell, and change gene expression in the cell. You think about puberty, the kid that goes home for the summer and then comes back looking completely different. Well, that's because of a lot of genes got turned on by steroid hormones like testosterone and estrogen.

But the story harmons can also have very fast acting effects. And with testosterone in particularly, those can be remarkably fast acting. And one of the most apparent and well documented fast acting effects is this effect, the ability to activate cells within the amiga.

He might say, well, I thought the amiga was associated with fear. Won't test also on then cause fear? no. Turns out that the amiga a harbors both tisa cortical stern receptors and testosterone receptors, and they eat, adjust activity in the amiga differently, such that testosterone tends to activate a mega circuitry for inducing states of mind and body that are more action based.

And indeed, in animals and in humans, testosterone application and activation of this critical media emigre pathway will make animals and humans lean into effort. This is why, say, to stop tron makes effort feel good, at least biases the organism told, leaning into chAllenge. So if you're call, there's not just one type of aggression.

There's reactive aggression, which is triggered when one is confronted with something that sometimes is inevitable, right? One needs to fight for their life, or for somebody else's is life. But also pro active aggression.

And pro active aggression involves activation of those go pathways in the basal ganglia, and they leaning into effort to overcome whatever state what happens to be in to begin with. And so this is very important because IT points to the fact that, yes, estrogen is activating aggression pathways that are in the venture menu hypothetic almas. But it's very likely the case that testosterone is acting to.

Accelerate or to bias states of minded body tored those that will lead to aggression. Again, aggression is not like a switch on and off. It's a process that has a beginning, a middle and an end.

Remember that hydroid pressure that on red Lorenz hypothesized, well, think of testosterone as increasing the pressure tard, an aggressive episode and an eggan actually trigger ing that aggressive episode in the venture media of hypothermia. So if somebody tells you that testosterone and dog genus or exogenous makes people aggressive, tell them, no, testosterone tends to make people lean into effort. And if that effort involves being aggressive, either reactive, ly aggressive or proactively aggressive, well, then I will indeed lead to aggression.

But the actual aggression itself is triggered by estrogen, not test astro. Now, thus far, we really haven't talked too much about the social context in which aggression occurs. And that's because there is a near infinite, if not infinite, number of variables that will determine that.

So for instance, violent aggression is entirely appropriate at a professional boxing match, provided is occurring inside the ring and only between the competitors and within the bounds of the rules of the sport. At seta. However, there are are some things that tend to bias certain social context toward being more aggressive or less aggressive, and not always physical aggression.

And those generally come in two forms that many of you are familiar with, which are alcohol and caffeine. Let's discuss caffeine first. Why would caffeine increase aggressive impulsivity? Well, the general effects of caffeine are to increase atomic of the activity of the so called sympathetic ARM of the automatic nervous system, which is to put IT very much in plane e language is the alertness ARM of your nerve system.

That is, IT creates a sense of readiness in your brain and body. And IT does so by activating the so called sympathetic chain. Gangly again, as I always remind people, simply sympathetic does not mean sympathy, simple means together, or all at once.

And caffeine intends to bias our brain and body to activate the sympathetic chain gang lay, which run from about the base of your neck until the top your pElvis, and deploy a bunch of chemicals that jumped out into the rest of your body. Activate a general in release. There's a parallel increase in of a journal in your brain creating the state of alertness, ss, and readiness.

That state of alertness and readiness can be for all sorts of things, not just aggression. However, when we are in a state of increased sympathetic tone, meaning more alert, such as after drinking caffeine, we will buy us all those brain and body systems that hormones, the chemicals that at that exists toward action, is opposed to in action. So put simply, caine can increase in cultivation.

No surprise there. On the opposite end of things, alcohol tends to decrease activity in the sympathetic ARM of the automobile system tends to make us feel less alert. Now initially, IT can create a state of alertness because of its effects in inhibiting the forebrain.

Our forebrain preferences cortex, in particular, has, it's called top down inhibition. IT exerts a inhibitory or a quieting effect on some of the circuits of the hype athamas, such as the venture media hythe's as the way to concept. Ze, this is that your forebrain is able to rationalize and think clearly, and to suppress behavior and to engage the logo pathways.

Ds telling you, don't say that mean thing, don't do that violent thing. That said, a alcohol initially tends to increase our level of overall activity by reducing inhibition, not just in that four brain circuit, but in other circuits, tend to make us more active. We tend to talk more than we Normally would, move more than we Normally would.

But very shortly there after starts acting as a seditions by way of reducing activity in the forebrain, releasing some of the deeper brain circuits that are involved in in pulse vary, but also causing a somewhat set up of effect. And then, of course, as alcoa levels increase even further, people eventually will pass out black out at such a. So what we've got with alcohol, caffeine, is we've get two opposites.

Ts of the spectrography increasing our sal in and readiness and the tendency for impulsivity. And alcohol also increasing impulsivity, but through a different mechanism. A really interesting study, and I should just mentioned that the title of the study is located and non c alcohol use and interact aggression at the impact of self regulation.

The tiles also story. This is a paper publishing the journal addictive behavior in twenty sixteen, examining how injection of alcohol that's either caffeinated or non cafe ated alcohol drinks impacted what they call indirect aggression. And just to remind you what indirect of aggression is, these are not physical acts of aggression.

These are verbal acts of aggression. So embarrassing others or otherwise, somehow trying to reduce the well being of others by saying certain things, in particular in groups. This study examined both males and females. This was done out by way of college campus study. Subjects were eighteen to forty seven years old.

I can see some older students on that campus or maybe they use some non students, but know these days you've also got some students that are in their thirties and forties so they have a fairly broad swath of subjects, included fairly brought racial background as well, included not equal numbers but um at least they included a pretty broad spectrum of people, different backgrounds they looked in, particularly people that ingested non caffeinated alcohol drinks at a frequency of nine point one eight drinks per week OK. Again, there's a college campus. Not that I encourage that.

I'm when these people that i've never really liked drugs or alcohol and it's our fortune in that way, drink or not drink and tend to not drink um but so to me nine point eight drink one eight drinks per week sounds like a lot. But I know for some people that that might actually be typical and then others who were drinking at least one caffeinated alcoholic beverage per week and those individuals um and as high, I should say as seven point eight seven coffee alcohol beverages per week. So this would be energy drinks combined, typically with hard alcohol that's fairly commonly available in bars in so fourth.

And some individuals drank as much as goodness twenty point three six alcohol drinks per weak total, some that were cafe ated, some that were not cafe at. The basic outcome of the study was that the more alcohol someone intended to consume, the more likely IT was that they would engage in these indirect, aggressive, tight behaviors. And in terms of the caffeinated alcoholic beverages there, the effect was especially interesting.

Here, i'm just going to paraphrase, are actually read from the study. Well, with regard to cafe ated alcoholic beverages, our findings indicated that heavy caffeine alcohol beverages was associated positive ly with interact aggression even after considering one's typical alcohol use and dispositional aggression. What this means is that even though alcohol can buy a certain individuals to be more aggressive, and even though certain individuals already have a disposition to are being more aggressive, there was, in effect, that was independent, meaning above and beyond both alcohol ena prey disposition, meaning if someone was consuming caffeinated alcoholic beverages, they had a particularly high likelihood of engaging in indirect aggressive behavior.

Now this makes perfect sense in light of the model they propose, which is this self regulation model, that basic self regulation involves several things that involves engaging in certain behaviors and suppressing other behaviors. So as describe before, because alcohol tends to have a sensitive suppressive effect on the autonomic nervous system, at least after the initial period, is going to tend to reduce the likelihood that people will engage in any type of behavior, where as caffeine will increase autonomic alle and increase the likelihood that someone will engage in a particular type of behavior, aggressive or otherwise. So the combination of caffeine and alcohol is really acting as a two pronged system to bias people towards more impulsivity, that is, less self regulation.

So it's really yanking your violation control, your ability to engage in prefrontal top down innovation over your yathrib as from two distinct and specific circuits. By now, you should be getting the impression that self regulation is a key feature of whether or not somebody, maybe when you is going to engage in aggressive speech or aggressive behavior. And we've talked about a number of tools that one can use to reduce the probability that, that will happen.

I suppose if the context were appropriate, you could even take those tall recommendations and just invert them and increase the likelihood aggressively what to happen. But regardless, self regulation is key. And in light of that, I want to share with you a study that focused on kids.

But that has important ramifications for adults as well as you probably are already aware, there are many kids out there that suffer from so called attention deficit hybrid activity disorder, A D H. There are also many adults we are finding that are suffering from hd. And there is also an epidemic, I would say, of people that are concerned about whether not they have addition now, whether not they have true clinical addition or not is not clear.

We did an episode all about add and tools for adhd. I would encourage to check out that episode in some of the diagnostic criteria. If you have the opportunity, can find that at huberman lab out com.

As this study i'm about to share with you, apple points out there is no objective diagnostic marker of A D H. There's no biomarker blood draw blood test for A D H D. Whether not one has adhd depends on their performance on a number of different cognitive tests and behavioral tests and self report.

In any event, the study is about to share with you explored how a particular pattern of supplementation in kids with A D H D was able to reduce aggressive episodes and impulsivity and increase self regulation. And the title this study is efficacy of courtine in the treatment of children with attention deficit hyperactivity disorder, even though they put carnett in the title that what they focused on was whether not a sidle l carney. Supplementation could somehow adjust the behavioral tendency of these kids with adhd.

And to make a long story short indeed, IT did. There was a very significant effect of a city carting supplementation on improving some of the symptom, symptom logy. Excuse me of add a few details about the study that might be relevant to you.

This was a analyzed double blind plus eval control double cross over study. This was done as an outpatient study. So the kids weren't in a hospital.

They were living out in the world. This, again, was done on Younger kids. So this was six, six to thirteen year old kids that were diagnosed with add.

They received either a cdl carneta or placebo. And they did all the good practice, stuff that good researchers do, of making sure that the placebo in the S. C.

L. County had similar looking taste. IT was consumed twice daily after meals. SHE has mentioned the seed of all countee typically is taken in capsule form, uh, or occasionally an injectable form.

Here they were using this as a drink, which essentially the same as caps of form, but the powders just going directly into liquid. And the current team dosage was one hundred milligrams per kilograms. So they're doing this according to the body way of these kids with a maximum dosage of four grams per day.

The quantity of the medication was supplied here i'm reading for a period of eight weeks and every eight weeks a new quantity of medication was supplied. So basically this is a fairly long term study um expLoring behavioral outcomes and psychological outcomes. In week eight, sixteen and twenty four they also looked at blood, things that you could only get through a blood draw. So things like him move and medical. Red blood sell count, White blood sell count, that these are kids and and even if they were adults.

So they were quite appropriately examining a lot of the physiological measures that one would want to Carry out to make sure, first of all that blood levels of curtain are increasing and indeed they confirm that but also that no um negative effects are showing up in the physiology as well as psychology of these kids so first i'll just tell you the basic outcome. The study which was here in pair, phrased ing, given twice daily cardinal, appear to be effective and well tolerated treatment for a group of children with A D. H.

D. They showed significant the abNormal behavior compared to these other boys. And now i'm moving to the table of results.

They showed significant reductions in their so called total problems score. The total problem score is a well establish measure of behavioral problems in kids with A D. H. C. And I should say, adults with A D H has to do with chAllenges in social and learning environments and how well or poorly an individual tends to perform, reductions in attentional problems, overall reductions in delinquency and most important, for sake of today's discussion, significant reductions in aggressive behavior.

Now what's especially nice about the study, I think, is that even though is a relatively small number of subjects and certainly IT needs to be repeated in other studies and other laboratories, that they were able to confirm the shifts in alcorn within the bloodstream of these kids, that is, they were able to correct the physiology with the psychological changes in studies like this, and Frankly, in all studies of human arma ology. You have to worry about effects that show up not just because of placebo effects, but because of so called off target effects or related things totally independent of the drug or the particular supplement that you happen to be looking at. To put in the words of, uh, a great news, science, unfortunate.

He passed away a some years ago, but he was, remember, the national academy, extremely accomplished neuroscientists once turned to me and said, never forget a drug as a substance that, when injected into an animal or a human being, creates a paper, meaning you can see effects of pretty much any drug, any supplement, in most all conditions. However, IT is in cases such as this study, where you can quite convincingly see that the particular feature of physiology that you expected to change actually changed. And you see a psychological outcome that you can gain much greater confidence that the changes in delicacy, in this case, reduced del quercy, improve detention, reduce aggressiveness and so forth, was least somehow related to the shift in blood physiology and levels of l carnet, or a cil carnet and carney in the bloodstream of these children, as opposed to something else like all currency going and affecting some downstream target that you have no knowledge of.

Now, of course, that's still entirely possible, but I think studies such as these increase our confidence that things like l carnet can be used perhaps in concert with things like mega three supplementation diets that are biased towards increasing more trip to fan and therefore more serotonin. Obviously avoiding things like alcohol. And as IT appears from the study I just described, reducing once in take or not consuming any caffeine alcoholic beverages seems like a be a good idea if your goal is to reduce aggressively, to think about the hormone context and whether not you tend to have higher testosterone estermen or lower testoon a gen.

Maybe you can think about the work environment, whether not you are existing in a particularly competitive work environment and even daylight time of year, and whether or not you're getting sufficient sunlight, whether not you're avoiding light in the evening and so on. So studies such as this, I think we're useful because they point to the fact that very seldom, if ever, will there be one supplement or one nutritional change or even one behavioral change that's going to completely shift an individual from being aggressive and impulsive. But rather that by combining different behavioral regiments, by paying attention to things like time of year and work conditions and school conditions and overall levels of stress and likely, therefore, levels of cortisol, ta that you can use behaviors, diet and supplementation as a way to shift that overall internal mill you from one of providing a lot of internal hydro ic pressure, as it's been called through the episode tored aggressive impulsivity and relax some of that hydraulic c pressure and reduce aggressive tendencies.

So once again, and Frankly, as always, we've done a deep dive into the neurology and the psychology of what I believe to be an important feature of our lives, in this case, aggression. Want to point out that in a episode in the not too distant future, i'm going to be hosting doctor professor David Anderson from celtel university, who is the world expert on the neurobiology of aggression. In fact, he is the senior author on many of the studies related to the venture media hypo films that I discuss today.

Our discussion will touch on aggression, of course, so hearing today's episode will help you digest that information. But we are also going to talk about other emotional states he is an expert notice in aggression but in motivated states related to sex, in mating behavior um social relationships of all kinds and how those relate not just a biology and psychology but also certain forms of pathology, things like P T S D and the relationship for between anger, fear, anxiety and depression and many other important topics that I know many of you, if not all of you, will be interested in. In the meantime, I want to point you to his recently released and wonderful book entitled that the nature of the beast, how emotions guide us.

And again, the author is David Anderson from caltech. This is a wonderful book. IT serves as a tremendous introduction to the history of the study of these areas, the current science and discoveries being made in these areas, all made accessible to the scientists and non scientists.

Like it's a very engaging read. And so much so that even though he was gracious and sending me a copy, I also purchased myself a copy give to somebody who is a therapies. And I ve purchased another copy to give to a high school kid that I mentor, because he's very interested in the neuroscience of emotions.

And I think we are all interested in emotions, not just fear and some of these negative states, not just aggression, but also the positive emotions of our lives. And so the nature of the beast tow w emotion guide us by David Anderson is a wonderful read. I can't recommend IT highly enough.

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