December 30, 2010 • 29 mins
Each week, you can count on Robert and Julie to blow your mind with the latest -- and strangest -- stories from the world of science. Tune in and learn more in this episode.
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Speaker 1 (00:03):
Welcome to Stuff to Blow Your Mind from how Stuff
Works dot com. Hey, welcome to Stuff to Blow your Mind. Uh.
This is Robert Lamb and I'm Julie Douglas and we
were just talking about food prior to Jerry rushing us
in here to actually record the podcast, about about how
(00:26):
satisfying a meal can be to the to the soul,
but it can also have a huge effect on the mind,
as we're going to get into in this particular podcast.
That's right, and what I'm thinking about specifically, are butterflies
in the stomach. Have you ever felt that? I'm sure
you have. Yeah, and yeah, definitely definitely, not so much recently,
(00:47):
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
(01:07):
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
(01:28):
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
(01:50):
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
(02:13):
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
(02:33):
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
(02:57):
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
(03:19):
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
(03:39):
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
(04:00):
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.
(04:23):
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,
(04:46):
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
(05:09):
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,
(05:30):
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
(05:50):
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
(06:13):
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.
(06:33):
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
(06:55):
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
(07:16):
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.
(07:38):
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
(07:59):
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
(08:22):
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
(08:43):
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,
(09:03):
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
(09:24):
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
(09:46):
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
(10:08):
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
(10:31):
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.
(10:52):
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,
(11:13):
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
(11:37):
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
(11:59):
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
(12:20):
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
(12:41):
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
(13:04):
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
(13:26):
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
(13:48):
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
(14:10):
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,
(14:30):
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
(14:51):
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
(15:13):
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
(15:33):
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
(15:53):
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,
(16:16):
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
(16:38):
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.
(17:00):
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
(17:21):
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
(17:44):
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
(18:06):
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
(18:27):
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
(18:47):
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
(19:12):
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
(19:32):
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
(19:53):
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.
(20:15):
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
(20:35):
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
(20:58):
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,
(21:18):
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
(21:39):
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
(22:00):
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
(22:21):
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
(22:43):
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,
(23:05):
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
(23:26):
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
(23:48):
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.
(24:09):
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
(24:30):
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
(24:52):
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.
(25:13):
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
(25:36):
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
(25:58):
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
(26:19):
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
(26:41):
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
(27:02):
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
(27:23):
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
(27:45):
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
(28:08):
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
(28:30):
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
(28:54):
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email us at Blow the Mind at how to works
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(29:15):
app has a ride. Download it today on iTunes. Who
Welcome to Stuff to Blow Your Mind from how Stuff
Works dot com. Hey, welcome to Stuff to Blow your Mind. Uh.
This is Robert Lamb and I'm Julie Douglas and we
were just talking about food prior to Jerry rushing us
in here to actually record the podcast, about about how
(00:26):
satisfying a meal can be to the to the soul,
but it can also have a huge effect on the mind,
as we're going to get into in this particular podcast.
That's right, and what I'm thinking about specifically, are butterflies
in the stomach. Have you ever felt that? I'm sure
you have. Yeah, and yeah, definitely definitely, not so much recently,
(00:47):
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
(01:07):
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
(01:28):
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
(01:50):
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
(02:13):
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
(02:33):
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
(02:57):
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
(03:19):
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
(03:39):
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
(04:00):
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.
(04:23):
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,
(04:46):
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
(05:09):
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,
(05:30):
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
(05:50):
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
(06:13):
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.
(06:33):
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
(06:55):
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
(07:16):
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.
(07:38):
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
(07:59):
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
(08:22):
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
(08:43):
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,
(09:03):
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
(09:24):
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
(09:46):
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
(10:08):
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
(10:31):
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.
(10:52):
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,
(11:13):
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
(11:37):
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
(11:59):
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
(12:20):
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
(12:41):
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
(13:04):
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
(13:26):
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
(13:48):
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
(14:10):
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,
(14:30):
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
(14:51):
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
(15:13):
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
(15:33):
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
(15:53):
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,
(16:16):
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
(16:38):
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.
(17:00):
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
(17:21):
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
(17:44):
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
(18:06):
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
(18:27):
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
(18:47):
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
(19:12):
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
(19:32):
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
(19:53):
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.
(20:15):
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
(20:35):
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
(20:58):
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,
(21:18):
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
(21:39):
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
(22:00):
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
(22:21):
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
(22:43):
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,
(23:05):
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
(23:26):
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
(23:48):
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.
(24:09):
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
(24:30):
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
(24:52):
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.
(25:13):
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
(25:36):
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
(25:58):
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
(26:19):
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
(26:41):
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
(27:02):
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
(27:23):
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
(27:45):
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
(28:08):
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
(28:30):
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
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(28:54):
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