Is your gut a genius?

in the stomach. Have you ever felt that? I'm sure you have. Yeah, and yeah, definitely definitely, not so much recently, but certainly the earlier podcast I would always get get

butterflies the old days, like a year ago. Yeah, yeah, And I think that when I first started, I actually mentioned to you once that my sphincter was talking to me and had a horrified look on your face, and I wanted to explain to you that I was having an emotional response manifested in my vowels, but I didn't know you well enough then we I either blocked that comment entirely or um or didn't hear you. So yeah,

I think you blocked it. Yeah, yeah, But I think the reason why we're talking about this today is that there really is quite u a symbiotic thing going on between the brain and the gut that we're just now really discovering. Yeah, and when you do, when you have a satisfying meal, like the effects that can have on on the mind or or even if it's not satisfying, just like an nutritious meal, and it's the effects on the brain. We're gonna discuss some of that in this

particular podcast. Now. The idea of feeling something in your gut, I mean, this is just a common phrase. I've got a got a gut feeling about this instinct, yeah, and and it goes back. It's it's it's a pretty old thing, an old concept, and it's easy to think of it into in the same same terms as like when someone says they have a feeling in their heart, because unless you're having like a heart attack, you know, there's a you're probably not really feeling anything like when you love somebody.

It's that really doesn't have anything to do with your cardiovascular system, right, and yet you feel this in heartache to an unrequited love, right, Yes, I have a great quote here. That's a from a speech to the English troops um to rally them against the Spanish Armada by Queen Elizabeth the First, and she's reported to have said, quote, I know I have the body of a weak and feeble woman, but I have the heart and stomach of a king, and a king of England too. So well

see there's a great you know example. She's like, she's like, you know, I maybe be a lady, but I've got one heck of a heart and one heck of a stomach.

She was invoking gut power. And there was a right across another like really interesting thing from a Dutchman by the name of Levinus Limnius Um and L yeah, l l and uh in this is back in the He had this whole thing where he's talking about how about the stomachs of the English and the Scots, and uh he had this whole bit about how though they will quote stomach a matter of eminently and a long time lodge an inward grudge in their hearts, whereby it happeneth

that when their rage is up, they will not easily be pacified. Neither can They're high and haughty stomachs is or stomach is. It's weird spelling. Lightly be conquered otherwise than by submission and yielding to their mind and appetite. So there's just more of you, you know, it's getting

the stomach and the heart. You know, these these older accounts and uh, and people were identifying like that is a it's a seat of who you are, Like if you want to you want to get to the if you want to get to the you know the quote heart of the matter on on. You know what makes an Englishman or a Scotsman look at their stomach? Great stomach specimens these guys hence yes, yes, they're like you want to here it is it's actually it's not a pleae Scott's stomach. But anyway, but I think what I

think they were onto something there. Yeah, yeah, I think we in recent ages we we kind of got more into that brain. You know, it's all about the brain and then you know everything else is just you know, plumbing. You know, yeah, it's just the generator to power it.

But it's not the case, um I really at all. No. No. In fact, it was a Dr Michael Gershon who coined the term the second brain when referring to the gut because he actually brought in in into um into everybody's uh conscious the fact that the gut is doing so much more and has a lot more complexity to us than we ever realized. And I mean, like you said, people had an instinct maybe that their gut was pretty important.

And in fact, in the eighteen hundreds, scientists and doctors began to make observations about the effects of the emotions on the brain. And in nineteen o two they actually did a study where they had a dog growl at a cat and then they watched and noticed, uh I think they used barium, and they noticed that the digestion started to slow down as the cat was growled at

by the dog. And again, this is like a trackable substance in the digestive system, so they can see at what rate the cat's digestion system is moving right exactly, so they could see this happening, and they went, ah, eureka, the cats stressed and it's not it's not going to poop us soon exactly, yeah, exactly, which is which seems crazy that these scientists we even have to carry this out, because I mean, had they never been on a vacation before had they you know, they never I mean it

seems like I think everybody out there can probably attest to there being some situation in their life where they were out of there, you know, out of their their comfy surroundings, and in their digestion changed in some way, shape or form. Like I've talked to two friends who like went on vacations and they're like, They're like, yeah, I was on my second day there and I still

hadn't pooped. I don't know what was wrong with me, you know, And it's just your again, your your digestion system is altering to what may be a new rhythm, a new uh um, you know, a new level of stress coming at you right right, Yeah. And then emotionally too, I mean, things happen and then all of a sudden, you know, your stomach starts to turn and twist and think,

oh my gosh. But the thing that scientists, specifically neuro gaster intrologists, are starting to figure out is that it's not so much that your emotions are acting on your brain. It may actually be that your gut, your second brain, is responsible for initiating these responses in the first place. Yeah, and in some of the ways that, uh, that this is happening. It it makes me think of the stomach not so much as a second brain, but kind of like a satellite office, yes, for the you know, for

the brain, the brain being the home office. Um, like just some of the neural circuitry. I guess you could say that it's while death in the stomach is pretty neat. Yeah, And it's a really good design if you think about it, that that neural circuitry is right next to the digestive system, right, because why would the brain expend the energy to send a hundred million neurons you know, down to do the job when it could just put it right there in that what we call the entric nervous system, which is

embedded in the lining of the gastro intestinal system. So it's really smart, sort of like putting the electrical panel right where it's needed. And this this system is actually independent in that it can start digestion processes independent of the brain. It can get a lot of things going. Um. As I mentioned, there are a hundred million neurons, which is more than the spinal cord and the peripheral nervous system. There are five hundred million nerve cells and it uses

thirty transmitters neurotransmitters, just like the brain does. Like back in the day, this was thought to be nuts, this whole entric nervous system, and in fact it was first described by a British physician, but he was pretty much smacked down because people thought, no, no, it's all the brain.

The brain is doing it, um, and so they're actually Gershawan pointed out that that making that sort of claim that there was this entering system was like saying that New York taxi drivers never miss a showing of Tasca at the met Yeah. So, I mean obviously they didn't know how important the gut is and how much it regulates our thoughts are feelings. And that's right, that's Tusca is an opera. I was about to sing an operatic note. That's a let's not do that. Let's not talk about

poop and sing opera. It's just not gonna. That's not a good pairing. Um. But so anyway, that goes back to that sensation of feeling. You do feel things in your gut because you do have all of that stuff going on. And this is another crazy fact that of the fibers and the primary visceral nerve just called the bad just carrious information from the gut to the brain, and that means that communication is mostly one way. This is a one way situation with the gut communicating the

time to the brain. I mean that was a chatty, chatty gut. Yeah. You made a great analogy earlier about about the teenagers in love. Yeah, yeah, sort of like yeah, teenagers in love, you know, getting on the phone all the time. You're like, what are you doing? What do you do? Know? What are you doing? What does this mean? What does that mean? I mean, literally, the gut is doing the same sort of thing and constantly giving the brain all of this information about what's going on in

the gut. Yeah, satellite office constantly checking with the home office and saying, hey, we just did this, Hey we just did that. Yeah, yeah, I'm feeling this way. I don't know, I'm a little bit anxious. What about you? And so the brain is actually getting these these messages of anxiety, and it's backwards from what we thought before. Right, we thought the braining was sending the gut messages saying hey,

I'm not feeling so great. As a sci fi fan, I can't help but think of the just the many examples of you know, these like head head in and jar kind of situations or like head transplants, you know, where it's like the the human head or even just the brain you know, as the seat of who we are taken and like say attached to a robot body

or put in another body, etcetera. And I And granted there's some sort of there's some grotesque aspects of that that are you know, could be troubling, but in a in a way, it's also a very kind of enlightened, kind of enlightening kind of view where it's like, I'm my brain and everything that I am really doesn't have anything to do with all this gross stuff going on in my in my stomach and elsewhere, you know, So it's kind of this like liberation from from all things

related to a digestion and poop and all that. But in reality, you have to look at it from more of a holistic standpoint where you know, we're, yeah, we we are in a sense, we are just our brains. But I thought you're gonna say we are are poop. No no, no, no, no no, but no, it's like we are our brains, but we are we are, but

the brains connected everything else. It's like we are this system, We're are this this, uh this organism and uh and if you start trying to cut one system from the next and trying to isolate who and what we are to one particular part of that organism, it gets kind of problem It gets rather problematic. Yeah, yeah, I know, I think we need to step away from the brain centric and look at this a gut in a more serious light. Um, especially the interplay between the gut and

the brain and specifically serotonin. Yes, this is a big one. This is the the what is known as the mood neurotransmitter, and it's responsible, um when not insufficient quantity for actually they think causing depression. So so yeah, if you've ever dealt with depression or just or have ever walked into a health store and then you've probably seen serotonin sited on numerous bottles of either prescription medicine or um mysterious

vitamin pills. Right, and so just so you can kind of get a better contact too of how important serotonin is. Of our forty million brain cells, most are affected by serotonin. So this includes the brain cells as we said, related to mood, but also sexual desire and function, appetite, sleep, memory and learning, uh, temper temperature regulation, and some sort of social behaviors such as you know sometimes when we get manic or aggressive, that's attributed to low serotonin levels.

So the crazy thing about this is that your gut in mine houses of our serotonin available to us, which is nuts if you think about it. Yeah, and then you also look at serotonin and depression, and you look at antidepressants, and we know that with antidepressants also called ssr I selective serotonin reuptake inhibitors, that those increase serotonin

levels in the brain in the improved mood. Okay, okay, So we can't actually measure how much serotonin is in the brain, but we do know that if we give someone a bunch of depressants that it helps to increase the serotone and it makes us feel a lot better. So it searched to beg the question of what's going on in the gut and whether or not there are imbalances in the gut there which are causing disorders depression, um even related to Parkinson's for instance. This presentation is

brought to you by Intel sponsors of tomorrow now mentioned disorders. Um, it's I think it's important to then touch on disorders that we've long attributed to is more of a gut centric thing, such as IBS. Right, irritable bowel syndrome. Uh and in in in, I don't know, can you do?

Can you describe what your bow syndrome is? It's basically brought on by anxiety and depression because this is what we thought about are typically in the past, and this manifests itself with diarrhea, cramping, and it's I mean, it's awful, right, it's it's debilitating. It's not just so you know, I've got a stomach ache. It can be really horrible for people. And it's like a day by day thing. It's not like,

you know, it's chronic ate something weird. No, yeah, yeah, And it affects of the American population, which is crazy. So the previous answer was, oh, you have IBS, Well, you know, it's it's all psychosomatic. You need to cheer. Basically, you need to get your get your mind together and then your bowel will follow. That's a song, right, yeah, for your mind. Uh. But but what they're starting to figure out is that people with IBS don't have enough

sert in. SERT is basically a serotonin transmitter, which, um whisks serotonin out of your digestive lining. And so let me back up a little bit. Serotonin one of its jobs is to leak it off into your gut and basically start the digested digestion process, right, So it basically signals, hey, that we need to go ahead and start breaking this down. But if you've got IBS, you you've got the serotonin floating around in your gut and you don't have enough

of that set to take it all away. So what happens is that you just you've got horrible things going on your digestic system that you cannot stop. So it's an imbalance in your gut. It's not necessarily brought on by anxiety or depression. Those are actually the secondary results of that now there. But there's also the argument right that that, I mean, the whole idea of not being able to leave your toilet for an extended period of

time is pretty depressing. So um, yeah, I guess there's that chicken egg question, right, Yes, Like maybe maybe I'm a mind am I you know, do I have irritable bowsing room because I'm depressed or am I depressed because I have irritable bow syndrome? Who's running this show? The brain or the gut? Right? Right? And can I ever leave this toilet anytime soon? Yeah? I can see how

that would be depressing. But I think it's a really interesting piece of research that's emerged, and it tells us a lot more about how our mood is actually being regulated by our gut. And some some scientists are even saying, well, maybe it's not especially with ibs and mental disorders, maybe it's not so much that the person is, you know, having these problems because they are anxious or they're depressed,

but maybe some mental illness of the gut itself. Because you can't blame someone for not having enough serat to whisk away the serotone and that just happens to be the way that their gut is, right, that's not necessarily um a primary factor of their disease. Now, this is an area of study, this the inter relation between gut and brain that that hopefully we're gonna have more and

more data on in the in the years ahead. And uh and it and it's it's kind of if you look at the medicine as a as a as a whole. It's like you've seen that, you know, nutritionists playing a more of a vital role in medicine, uh in recent years. So so I you know, I'm tempted to see those

as as two prongs of the same movement. You know, as we as we get to realize that that you know, more and more that we are what we eat and we are this full system and uh, you know it's it's you know, our what's what our brain, the chemicals are brain received, the chemicals are in our stomach. Deals

with that, it's all a part of of who we are. Yeah, And I think that another interesting aspect of this is, you know, we've talked about internal versus external, but there is one study in which young rats were separated from their mothers and the layer of cells that line the gut weakened and that allowed bacteria from their intestines and it stimulated a bunch of immune cells. So basically the

immune system went into full force. And so um, the person who noted this and in the rats said it's basically an adaptive response and that if they're born into a stressful, hostile environment, that nature programs them to be more vigilant and stress responsive in their future life. So this same doctor is a neurobiologist. Doctor Mayor said that sev of the patients that he treats for chronic gut disorders had experienced early childhood traumas like a parents divorce

or chronic illnesses or parents death. So there is still this relationship to how we are biologically responding to our external stimuli in a sense, um, I'll raise your rats with mice because I ran across an interesting study from Yale Medical School where there's a there's this a substance called guarillin, and this is released by the stomach when it's empty and triggers hunger by by binding to the hippothalamus and that's a part of the brain that controls

appetite and metabolism. However, the hormone is also known to interact with the hippocampus, which is the seat of learning and memory. So they injected mice with with with a little extra of this substance and found that the these mice consistently outperformed ordinary mice in memory and learning tests, and it was like a rate of like by like thirty or forty. And then they also um uh sapped some mice of of this particular substance and found that

they underperformed on test. So their argument was in this study was that if an animal was hungry, it needs

extra brain power to find that next meal. Um so, um, you know, cognitive brain is a you know, side effective hunger kind of argument, which I think is is kind of interesting and it makes me makes me think of like fasting situations, you know, where you know, especially you know, you look at like old biblical accounts that you know, someone will set out in the desert too fast and contemplate some you know, some huge problem or you know, or theological inquiry. You know. So it's kind of it's

it's interesting. When I fasted, I mainly just um felt grumpy, watched a lot of Buffy the Vampires air and chip My Tooth on my coffee mug. But but in a way I could I also there was like a weird you know, I don't know, it's you definitely feel the effects in your mind when when you do something like that, which just you know, underlines again the connection between the gut and the brain. Yeah. Yeah, and this is interesting too.

If if you don't sleep well, you actually the overproduced grelling right in your because your body thinks that since it didn't get enough rest, that it's in some sort of panic mode and eats more energy and you end up eating a lot the next day, which is again that whole balanced thing. And yeah, you're you're probably a little bit cranky, and uh, this is something we're going to touch on in a future podcast more. But you know, our gut is not just a part of us. It's

also an environment for a number of fascinating creatures. It's not just the ones we ate trillions of bacteria that greatly outnumber our own guts cells, which kind of makes a question about whether or not we're just host for them. Yeah. Yeah, if the if the contents, if the creatures in our stomach are dictating on the stomach behaves, and the stomach is talking to the brain, yeah, then maybe maybe these guys are the true masterminds of all the really stupid stuff.

That's what I was thinking. It's sort of like the matrix that we're just the host. It's not the aliens though, that were the energy for it's just the bacteria in there. I was really that you blew me away with this particular fact about how the generally the Japanese in particular, have bacteria in their guts that produce enzymes that help digest seaweeds, and North Americans tend to lack this same

property in their system. Yeah. Yeah, so there was some sort of exchange there between bacteria and man that found its way into the genome for for Japanese who ate sushi or eat sushi that we just don't have, which is again another indication of how crazy that gut is

and what that bacteria, that wiley bacteria is doing to us. Yeah. Like, so the next time you order seaweed salad at your favorite Japanese restaurant, think about it is you know, I look around that you had the restaurant and to say that guy's gut is going to do a lot better job than this, uh, the soul gout here. So it's say, sir, I admire digestions or don't say that really. So, hey, I have some listener mail here for us. We've had a number of really cool comments about recent podcast um

both sent to us via email and also on Facebook. Uh. So, here's one from a reader by the name of Thomas, and Thomas is responding to our podcast on which we probe daily in abductions. From a yeah, exactly, from a skeptics point of view, I should add for anyone who hasn't heard it and he had this to say, I've never been abducted or had any experience in which I

believe I've met a little green man. But I have epilepsy. Specifically, I have nocturnal, tonic, clonic, and complex partial suit Typically, they are all controlled with medication, so don't fear. However, what I want to tell you about is my experiences with the complex partial seizures. These seizures manifest as a sudden flashing box in the corner of my eye, accompanied

by tunnel vision. I mentioned this because I think your observations of the brain creating scenarios out of frightening experiences such as sleep paralysis are extremely astute and relevant to my complex partial seizures. Whine because in addition to the flashing box and tunnel vision, I become paranoid and my mind creates a scenario in which I believe someone is sneaking up on me just out of the corner of my vision. I believe this is caused by and by

of vulnerability, as my mind creates a scenario. So that was really interesting because in the podcast we discussed a number of things that can go on neurologically, right that that our brain ends up creating um a scenario for and that scenario and a lot of times ends up being an alien abduction encounter or an encounter with something conspirit world or a demon or or you know, or

any or any number of of paranormal experiences. Right, and all of those sort of experiences have different um palm marks. Uh that's that are similar force to right, right with

the person being in the room or being spirited away. Yeah, so um, so Thomas makes for sharing that with us, And if anybody else has any experiences like that that they that they either have misinterpreted as an abi an abduction or can easily see how it could be uh interpreted by the by the first experienced it as an alien abduction, then do tell us because we're very interested

to hear about that. We also heard from a listener by the amiable Elizabeth, who wanted to make a quick point regarding our podcast titled Evolutionary Hangover, and she says, quote, I'm fascinated by vestigial phrase. I'm a grad student in ecology and evolutionary biology. So it's really excited when I saw the topic pop up in my iTunes. However, I literally cringed that Robert Robert's suggestion that evolutionists somehow quote going on unquote too fastigial traits in case in cases

where we need them for the future. Uh, that just isn't how evolutionary. That just isn't how evolution works. There's no way a population could experience natural selection for future conditions. Evolution by natural selection occurs because individuals with certain um properties tend to, on average, to lead greater numbers of descendants than individuals with other propertis. Uh, that's an evolution is an essentiate force. So uh, a very good point

to make. I did to quote a creative writing professor of mine by the name of Alan Alan Wire. I did personify like a mad god a little bit in that podcast in order to to try and break it down. But it is yet, it is very important to realize that evolution does not does not really think about anything. It is not a independent entity. So so yes, keep that in mind as you as you listen to some of these analogies. But but definitely Elizabeth, thank you for

breaking that down force. She also sent us a couple of US studies relating um the human volmar and nasal organ and specifically, she pointed to a study in which they found that smelly t shirts could conceivably turn a member of the opposite sex on because it's the whole pheromones and yeah, and and they would be sniffing out someone who had a greater comparcity in their yeah, DNA or something. So that's uh far from subtle science the

whole issue of human pheromones. But anyway, Elizabeth, thanks for pointing out. We're always happy to hear feedback and uh clarifications from folks in the know, and we're lefty enough to have a number of visits as a number of listeners who fall into that category. We also received us an email back about our podcast about music in the Brain,

specifically about earworms. I had asked the question of there are other people out there who only have musical ear worms without lyrics, because I've I've often found that I don't really run into people who experience it's that, but I only get like tunes caught in my head, not the lyrics for the most part. And heard back from a listener of the name of Emily, and she says, hello, I was just writing I wanted to reassure Robert that, no, you're not the only one that gets lyricalist music stuck

in his head. This happens to me quite frequently, especially when it comes to musical acts such as Plaid and The Novo. And we followed up and she's actually a number a fan of a number of really cool musical choices such as Boards of Canada, so I have to get rid thumbs up to that as well. And then one more up on the music front, listener David writes, and it says, I'm in the same boat as Robert in the sense that I don't think I've ever heard

a lyrical earworm. Since childhood, all of my ear worms has been instrumental, and it's one of the reasons I became a musician. I was a really late bloomer musically and didn't touch my first instrument until I was sixteen due to the complete lack of funding for childhood music programs in the area I grew up in. And he goes on to say, now that I'm in college and taking proper musical music theory classes, I have expanded my

repertoire of instruments. Um, I knew we found just about the world of music that surrounds us that really redefined the way I view my life. So I found that really interesting as well. Yeah. Yeah, Actually we got a lot of feedback on that, and a lot of people uh said that they didn't have lyrics like you as well, which I thought was pretty surprising. I thought everybody has any musical yes, well yes, but yeah, but you know

a good one. You know, we would uh, we would love to hear back from people about this podcast though, about the interplay between the gut and the mind. Let us know what your gut is thinking about. You can find us on Twitter and on Facebook as Blow the Mind. We're constantly updating that and uh and by all means, if you like the show, check out that Facebook page

and critical like button. Uh and and also please do us a favorite going too iTunes if you like the show and leave us a little positive feedback, maybe you know some some nice generous star ratings. Indeed, and if you have any get instincts you want to share peace, email us at Blow the Mind at how to works dot com for more on this and thousands of other topics. Visit how stuff works dot com To learn more about the podcast. Click on the podcast icon in the upper

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