[Michael breathing heavily] [laughing nervously] Everyone is scared
of something. But is there some<i> thing</i> that everyone is scared of? What is the scariest thing
possible? ♪ [Michael]<i>
So what</i> is<i> the scariest thing?</i> - Is it thunder?
- [thunder crackles] Shadows? Being burned alive? [laughs nervously] [laughs evilly] No. It's also not heights
or needles, snakes, spiders, sharks-- those things can be scary
to some, sure, but not to all. So here's what I mean
by "scariest." I want a thing--
an object, an action, an idea-- that, at my disposal,
would be guaranteed
to elicit fear and panic in anyone who might
happen to walk into
this room right now, regardless of how old they were,
their cultural background, their abilities,
or even their neurology. An adventure towards
this ultimate terrible thing must necessarily focus
on the womb. No, not the kind you came from, but the womb in which
fear itself gestates: the mind. -[wind whistling]
-[thunder crashes] To find the scariest thing, we must understand
how fears are born. [thunder crashes] [projector whirring] ♪ Where are we going? [laughs evilly]
Don't worry about it. Only two things matter: one, I've got plenty of gas,
so what could go wrong? And two, our destination
is a little bit spooky and we're gonna learn. Because in order to truly grasp what makes
the one true scariest thing, well, we need to dive deeper
into how we learn fears. [monster growling] [Michael]<i>
To start out, I commissioned</i> <i> a fear-conditioning
demonstration on</i> me. <i> You've probably heard
that exposure therapy</i> <i> can help people
overcome their fears.</i> <i> Well, the same principles
can be used to create fears.</i> Hello, Michael?
I'm Dr. Tomislav Zbozinek
from Caltech, and today we're gonna do
some fear conditioning. Do you have
any heart conditions or any serious major
medical conditions? - No.
- Okay. You've done this
to people before. - Hundreds of times.
- And they were all okay? They were all okay. Yeah,
everything worked out okay. - All right, I'm ready.
- Okay, perfect. [Michael]<i> The protocol
for fear conditioning</i> <i> involves my being electrically
shocked and startled</i> <i> by the sound of a human scream</i> <i> in connection to visuals
I see on a screen.</i> <i> Bioelectric sensors</i> <i> monitor my body's
physiological reactions.</i> <i> For example, my perspiration,
an indirect measure of fear</i> <i> that you can't
consciously control.</i> Is this how you run this
at Caltech? - Yes, this is the exact--
- [laughs] Exactly the same way. - Minus the restraints,
of course.
- Oh, the-- Oh, okay. Yeah. Everything else
is solid fear conditioning-- - As your usual--?
- Yes. Absolutely. All right, I'm game.
Let's help science. [Michael]<i>
The goal of this procedure</i> <i> is to condition me
to be scared of something</i> <i> I've never feared before--</i> <i> a mundane, harmless
geometric shape--</i> <i> something normal people
don't find threatening at all.</i> - [electricity crackles,
recorded scream]
- Aaaah! -[electricity crackles]
-[recorded scream] Little bit more scared
of the square right now. -[electricity crackles]
-[recorded scream] [Michael]<i>
A clear pattern emerges.</i> <i> My senses are being assaulted</i> <i> only when the purple square
is onscreen.</i> -[electricity crackles]
-[recorded scream] [breathing heavily] <i> But am I actually
being conditioned</i> <i> to</i> fear<i> a purple square?</i> -[electricity crackles]
-[recorded scream] All right, Michael,
you're all done. - Hoo!
- How was it? Well, it felt like
I was one of Pavlov's dogs. I couldn't help
what I was doing, and I was being trained to do it
in response to something, and that something was an otherwise very unassuming
geometric shape. Exactly. With Pavlov's dogs,
he had a bell and food,
something positive at the end. But in fear conditioning,
we have something aversive
and negative at the end. [Michael]<i>
And it worked.</i> <i> Once my brain associated
the purple square</i> <i> with being shocked,</i> <i> my physiological response
to the square</i> <i> went up and stayed up.</i> <i> The mere appearance
of a simple geometric shape</i> <i> made me scared enough
to break a sweat.</i> The results show that you
physiologically really ramped up to that purple square,
specifically. You quickly learned to be afraid
on a physical level. You showed fear. I came in here today
normal old Michael, but I'm leaving
as a brand-new Michael who is afraid
of purple squares. The human brain
can learn to be afraid
of almost anything. [Michael]<i>
To better understand
how this works,</i> <i> we need to look
at what's going
on neurologically.</i> What happens in the brain
during fear conditioning? Well, what we know
is that over evolution, over millions of years, we've developed these
defensive circuits in our brain. And the amygdala sits on
the front of the memory systems of the hippocampus. And the amygdala seems
to play an important role in determining
what the danger is of something in the world. It tells us what
we should be remembering, what we should be learning,
that is important to survival. [Michael]<i>
Our brain actually
has two amygdalae--</i> <i> one in each hemisphere.</i> <i> The function of the amygdalae</i> <i> is at the center
of fear research,</i> <i> which covers human behavior
ranging from the risk averse...</i> <i> to high risk-takers</i> <i> like free soloist Alex Honnold.</i> Ancient humans
who avoided danger and survived long enough
to reproduce became our ancestors. They populated the world
with creatures like us, organisms that instinctively
avoid and are averse to potentially dangerous
sensations. Things like pain and being sick, suffocation--
the need to breathe. We don't think those feel good, and you don't have to learn
to not like them. Even a newborn
is distressed by them, which makes them
"innate aversions." Fear is the anticipation
of these innate aversions. <i> When the purple square was
paired with electric shocks,</i> <i> my amygdala quickly made
that association</i> <i> and began consciously
and unconsciously</i> <i> arousing fear in me
whenever I saw it.</i> For this reason, I want us to
think of sensations as flies and our amygdala as
a meaty little spider spinning a web of fear. [thunder crackling] [Michael]<i>
The web is pre-stocked
with our innate aversions.</i> <i> Whenever an experience
is associated with
an innate aversion,</i> <i> it's like a fly
landing on the web.</i> <i> This alerts
the amygdala spider,</i> <i> which weaves
a powerful connection</i> <i> between that experience
and the innate aversion</i> <i> it's associated with.</i> <i> In my case,
that innate aversion was pain.</i> <i> which probably isn't the
scariest thing for everyone,</i> <i> because, well, some people
have a high pain tolerance.</i> <i> Others can learn to suppress</i> <i>
their fear of pain.</i> <i> And, of course,
some people enjoy pain.</i> <i> But the point is,
now that new experience</i> <i> will stay trapped</i> <i>
in your web of fear,</i> <i> a new member of the library
of things that scare you.</i> <i> To find the scariest thing,
we must wander through</i> <i> the darkest recesses
of the web.</i> Everything caught in
your web of fear is somehow connected
to death. Avoiding it--surviving-- is, after all,
what makes fear useful. It's why we are still here
today as a species. So if death is at
the very center of
all of our webs of fear, does that make death
the scariest thing? [Michael]<i>
Well, although many people
say death is their #1 fear,</i> <i> not everyone is afraid of it.</i> <i> Many acts of courage require
caring more about others</i> <i> than your own life.</i> <i> Some older people say
they're ready to die.</i> <i> And what about those
who commit suicide?</i> <i> Sadly, for them,
something else was scarier</i> <i> than ending their own life.</i> So death isn't exactly
the answer we're looking for. The scariest thing will
be something else on all
of our webs that is panic-inducing
even to those who want to die. [projector whirring] [car rattling] Dangnabbit!
Wouldn't ya know it?
I've run out of gas. Guess I'm just gonna
have to walk down this
desolate, foreboding road in search of a gas station. Luckily, this is just a movie. My rational mind
knows that I'm safe, and it will use that to inhibit
my amygdala's fear response. [laughs]
What a great way to make a horror film scarier,
right? Take away one of
the rational mind's shields, and the amygdala's fear response
won't be as inhibited. What we're about to see
really could happen, and perhaps...will. [Michael]<i>
Of course,
we don't just learn fears</i> <i> from firsthand experiences.</i> <i> Throughout our history,
we have used images and words</i> <i> to teach fears to one another,</i> <i> to prepare the next generation
for various dangers.</i> [narrator]<i>
These high school boy and girls</i> <i> are having a hop
at the local soda fountain,</i> <i> innocent of a new
and deadly menace</i> <i> lurking behind closed doors.</i> <i> Marijuana! The burning weed</i> <i> with its roots in hell.</i> Why do humans
have to tell stories
to share fears from generation to generation
and person to person? Language is virtual reality. So when you
tell someone a story, you're not just describing
a crocodile, for example, the language in the story
has a kind of emotional impact
on the listener. So when I tell you some
scary story about crocodiles, the amygdala is being activated
by the words and the scenarios, allowing the imagination
to sort of play with these ideas and scenarios,
so you're concocting imagery. So it has a double whammy. And you're getting
a very good sense that you should stay away
from this kind of thing
in the future. As a species, we're very
dependent and vulnerable
compared to other animals. We don't have
sharp teeth and big claws,
and we're not really fast-- it takes us years and years
to be self-sufficient. So what's happening during
those years of development is that we're getting
all this information about
the environment through stories. And part of that
is to know what to be afraid of
and what to not be afraid of. [projector whirring] [echoing]
Hello! -Hey, hello!
-[bird cawing] Whoo. Okay, being alone
is kind of scary, right? But you know what?
I'm actually not alone.
I am always connected. -<i> [ominous motif plays]</i>
- No reception. Of course. I mean, what is this,
a horror movie? Yes, it is. And you know what,
I'm actually getting
a little bit scared right now. A new fear, by the way,
has developed in just
the last few decades. You see, a while ago,
no one had a cell phone. No one was ever connected
through the internet constantly. But now many of us,
most of us, are. And so that's the new normal, and what's abnormal now
is<i> not</i> being connected, not having your phone. Psychologists
give that fear a name, it's a real thing
that's being studied, and it's called nomophobia. Anyway, the point is, the scariest thing possible--
hmm, what could it be? Well, an important ingredient
might be... [fly buzzing] <i> ...our innate aversion
to isolation.</i> Why are we afraid
of being alone? Human beings are social animals. We need each other to survive. So if we're alone, it lessens
our chances of survival. And there's been
a lot of research now that shows that when people
isolate socially, it actually leads to things
like increased heart problems, increased cancer risk,
physical issues, mortality. It is very much directly tied
to the sense of survival
and avoidance of death. What I find interesting
about isolation is, I think it helps us capture a lot of tertiary-and-beyond
fears that don't seem to be
directly connected to death, but<i> are,</i> in a way,
through isolation. For instance,
the fear of public speaking. Yes. Well, that taps
into your fear of rejection, and when you feel like
people don't like you,
you feel alone! And so putting yourself
out there, having that possible fear
of rejection when you're speaking in public and not knowing how people
are gonna perceive you, that's very scary
for a lot of people. Which doesn't
necessarily mean that you will directly die. However, it connects
to our innate aversion
to isolation which, through evolution,
we have learned is a bad thing
that can lead to death. - And so we're afraid of it,
avoid it.
- Absolutely. In the very first episode
of<i> Mind Field,</i> I spent 72 hours
in an isolation chamber. <i> For three days
I had no contact
with the outside world.</i> <i> I had no clock or window,
and the lights never went out.</i> The scariest part, though,
wasn't being alone. <i> I could handle that.
The worst part</i> was being separated
from the natural cycles
of the Earth I was so accustomed to. <i> Night and day. Time.</i> <i> The disorientation
and helplessness caused by that</i> <i> made me distressed,</i> and may have been a reason why, while in the room,
all of my dreams also took place
in the same room. <i> I soon became unable
to tell the difference</i> <i> between when I was dreaming
and when I was awake.</i> <i> I was terrified.</i> Extreme isolation like that
is not normal or healthy, but we all respond differently. There are people who love
living by themselves in the middle of nowhere. And with sufficient forewarning
of the effects, I think I could have
handled it better. So just being all alone probably isn't
the scariest thing. So then what is? [projector whirring] Ah. You know what
would make this scarier? Perfect. [wolf howling] [fly buzzing] Let's talk about
fear of the dark. Children and adults,
and myself, often,
don't like the dark. - No.
- Why? The sensory deprivation. It leads you to feel like
you're out of control, like you don't know
what's gonna be happening. And, at the same time, predators tend to
come out at night, so when we think back
to caveman days, they tend to attack
later on in the day
when you can't see them. And so there's a natural
inclination for us
to fear the dark, because we don't know
what's lurking out there and there's a lot of things
that can come and hurt us. My wife is pregnant
right now. I mean, it's pretty dark
inside my wife. Is my kid scared of the dark
in there? - Nope. Nope.
- Why? It's comforting for them.
And in fact, if a baby is colicky,
they can't be soothed, if you put them in a dark room,
they calm down. In fact,
this fear of darkness doesn't really come out
for most children until about the age of two. That's when, I think,
they start to develop
certain cognitive and neural memories and maps about things that might
be scary about the dark. For example, your parents
tend not to be in bed with you
necessarily. They're gone.
So these are the people
who were protecting you. Well, it's dark,
you're going to bed and they go to their room
and you're by yourself. So to answer the question,
"What's the scariest thing
possible," the darkness isn't necessarily
the best one, 'cause
if a newborn walked in-- well, I don't know
how they're walking,
but just go with me-- a newborn walks in,
it's not gonna be like,
"Aah! It's dark!" They'll just be like,
"Hmm." Right. "Hmm, it's kinda nice." And you know who else
isn't scared of the dark?
A blind person. Exactly. So darkness,
I'm crossing that off my list. Not universal. - [projector whirring]
- [wolf howling] [Michael]<i>
So if messing with our sense
of sight isn't scary enough,</i> <i> what about
our sense of hearing?</i> [woman screaming] Okay,
I'm pretty scared right now. But I could be more scared. [man screaming manically] [evil laughter] [chorus of screaming, cackling] Why is it so easy
to condition a fear
using sound? Sound has a specific
neural pathway in the brain which goes from
the auditory cortex, thalamus, straight
into the amygdala. Now, the funny thing
about sound is, our visual system
allows us to see a threat and prepare for it,
but sounds don't. The rustle of some leaves,
the footsteps in the distance, evokes anxiety, it evokes a situation which
we don't know how to respond, because we've not seen
a threat yet, we don't know
what it is. - Much less information.
- Yes. [thunder crashing] - [animal growls]
- [owl hoots] Sound is a very immediate
processing within the brain. So a loud sound
creates a startle
for anybody, immediately. - staccato chord plays]
- But also some of these
eerie sounds that you'll hear, they make
the hair on the back
of your neck stand up, it's basically hijacking
your fear system very directly. [ethereal noise echoing]<i>
Ch-ch-ch, ah-ah-ah...</i> <i> ch-ch-ch, ah-ah-ah...</i> [Patrick Brice]<i>
The first time I heard
the "ch-ch-ch...</i> ah-ah-ah, ch-ch-ch," from
the<i> Friday the 13th</i> movies, <i> that stuck with me forever.</i> - [gasping]
- [man groans] <i> [thunder crashing]</i> <i> [bucolic music playing]</i> [Sean Cunningham] <i>
Music tells you how
you're supposed to feel.</i> <i> [slashing violins playing]</i> [screaming] And I believe
that we are hardwired
to respond to music. <i> In dramatic musical writing,</i> <i> you can use all kinds
of different devices...</i> -<i> [ethereal sounds]</i>
- Must be my imagination. <i> ...to create fear.</i> -<i> [slashing violins play]</i>
- [screams] Here I am
walking through the woods. And here I am
walking through the woods... with scary music. <i> [violin playing
suspenseful motif]</i> [Michael]<i>
But if one note is scary...</i> <i> [introduces
dissonant harmonies]</i> <i> ...two notes
can be even scarier,</i> <i> especially
if they're dissonant.</i> [Dr. Asma]<i>
There are certain intervals,</i> <i> two notes that are clashing
with each other,</i> <i> that universally bother people.</i> They put you in a kind of almost
fight-or-flight situation. [Michael]<i>
Musical intervals that fall</i> <i> outside of conventional
harmonies</i> <i> may trigger our innate aversion
to things that are different</i> <i> or abnormal.</i> [dissonance continues] <i> This interval,
known as the "Devil's Tritone,"</i> <i> is so dissonant that composers
purposefully use it</i> <i> to make listeners
uncomfortable,</i> <i> from TV themes
like "The Twilight Zone..."</i> <i> [guitars play
dissonant harmony]</i> <i> ...to hard rock like the start</i> <i> of Jimi Hendrix's
"Purple Haze."</i> <i> [guitar playing tritone motif]</i> [raven cawing] <i> But music doesn't always
have to start out scary.</i> The right context
can make even the happiest song absolutely terrifying. [dissonant version of
"Pop Goes the Weasel" playing] [music continues,
girl humming along] [evil laughter] Once a song
has been conditioned
to elicit fear, the effect can be
extremely strong
and long-lasting. For example, the theme song
from "The Exorcist,"
"Tubular Bells." <i> Terrifying, right?
Go listen to it,
it's scary.</i> <i> But just a few months
before the movie came out,</i> <i> it was a chart-topping
pop hit that audiences loved</i> <i> because it was lighthearted
and fun.</i> Oh, strawberry. Very good. But here's the problem
with sound. Not everyone has been
conditioned to be afraid
of the same sounds or music, and not everyone can hear--
what about the deaf? Clearly, the scariest thing
possible to everyone - will not be a sound. <i>
- [girl laughs evilly]</i> Take a look at these paintings. We have a flirty little clown, an abstract piece,
and a landscape. Now, these paintings
may seem a little bit strange, but I wouldn't say
I'm freaked out by them, and I doubt you would either. But now let me give you
a bit more story-- the context behind these items. This picture was painted
by John Wayne Gacy, a serial killer
who tortured, raped, and killed 33 teenager boys
and young men. This was painted
by Chares Manson, the infamous cult leader
who convinced his followers to commit a series of nine
horrific murders in Los Angeles. And this landscape
was painted by... Adolf Hitler. Your thoughts about these items
have probably changed a bit. Psychologists call
this phenomenon the "Law of Contagion." It's our tendency
to imbue objects with the qualities of the people
they're associated with. Now, before and after
you heard the story, the items were still made
of the same molecules and atoms, but our minds use context to quickly endow them
with new powers. Now, these paintings
cannot hurt you, but the fact that the context
allows your amygdala spider to connect them
to other fears and, ultimately, through
your innate aversions, to death, means they take on
a whole new meaning. <i> The right story and context</i> <i> can make almost any object,
person, or place scary.</i> In fact, let me
ask you a question. What is this, behind me? Ah, you know what? This old camper
isn't actually that scary. Ahh, nuts. All right, things
are different now, and I'm starting to feel, yep, an automatic process
is already happening to my body. My amygdala now
associates this trailer
with death and danger. What I'm feeling is actually
the same thing that happens when you feel frisson. That's when you're greatly moved
by something profound. <i> What's happening
is that my amygdala</i> <i> is telling my hypothalamus</i> <i>
to tell my adrenal glands</i> <i> to start pumping adrenaline
into my bloodstream.</i> <i> This makes my arrector pili
muscles contract,</i> <i> which makes my hairs stand up.</i> <i> Now, if my body were covered
in thick fur like, say a cat,</i> <i> this would make me look bigger
and more threatening.</i> <i> But of course,
a long, long time ago,</i> <i> we humans lost
a lot of our fur.</i> <i> But we didn't lose this reflex,</i> <i> which makes it
a vestigial reflex,</i> <i> something we don't need anymore
but we still have.</i> <i> It is known as
the Piloerection Reflex</i> or, more commonly,
goosebumps. <i> Anything that's different
or abnormal can be scary.</i> Take it, Georgie. [Michael]<i>
Like Pennywise in "It,"</i> <i> oftentimes the scariest
type of predator</i> <i> isn't a human, a creature,
or a beast,</i> <i> it's a variation
of a human being...</i> [growling] <i> ...a distorted human form
that looks, acts,</i> <i> or even moves in
a disturbingly unnatural way.</i> Oh, my God. One thing many of us
are terrified by is a distorted human form. Why? Our brain and our mind is a kind of
prediction processor. We're trying to predict
what's gonna happen next. So when anything comes in
and it doesn't match
our template, or sense of categories, then we're cognitively
and emotionally aroused. So it activates the amygdala,
it makes us a little suspicious or at least puts us
on our toes again. We have a genetic predisposition to be averse to,
or at least aroused by, that which is outside
the ordinary. But when you're fresh
out of the womb, you don't know what's normal
or what's distorted and scary. Researchers are Princeton
and Florida Atlantic University demonstrated this
by showing normal faces and creepy, distorted faces...
to babies. <i> Children that were at least
one year old</i> <i> avoided looking
at the scary faces,
which makes sense.</i> <i> But younger children,</i> <i> like those who were
only eight months old, didn't.</i> <i> The hypothesis is
that at that age,</i> <i> normal hasn't yet been
sufficiently established.</i> <i> A creepy face is just
another thing to look at.</i> It only becomes creepy
when you've been around
long enough to know what's<i> not</i> creepy. So when it comes
to finding the one thing that can panic anyone,
I'll need to look elsewhere. Because if a newborn baby
rolls in here, I won't be able to scare it even with the most vile,
scary, unnatural face. Of course,
it's not just faces. Distorted natural forms
also include bodies, like humans
with other animal parts. [creature growling] Or creatures moving unnaturally. Oh, my. <i> Oh, my.</i> Hoo hoo hoo! "Oh, my," indeed. You know what's going on here, this is the third origin. Fears can be born through
firsthand experiences, like feeling pain, or informationally,
through stories, but we can also learn fear
vicariously by watching others
experience fear. [Michael]<i> It's called
Social Fear Transmission,</i> <i> and we tried it out out
during my fear conditioning
demonstration.</i> <i> Our unknowing subject was
my good friend Alie Ward.</i> <i> Alie was invited to observe
my experience</i> <i> and witness my reactions.</i> - [electricity crackling,
recorded scream]
- [Michael] Jeez! Okay, little bit more scared
of the square right now. [Michael]<i>
Right after my test,</i> <i> it was her turn to face
the green circle</i> <i> and the purple square</i> <i> that appeared
whenever I got shocked.</i> [Dr. Zbozinek]
We're gonna use the same
shock intensity - that Michael had.
- Okay. [Michael]<i>
Except, that wasn't true.</i> <i> Alie's test would not
include any shocks
or startling sounds.</i> [Alie] Is it normal to be
shaking before this? [laughs] Yeah, it's an anxiety-provoking
task. Are you feeling okay - about doing it?
- Mmm-hmm. Sure. [Michael]<i>
Would Alie be afraid
of the purple square</i> <i> just from observing
my fear of it?</i> - You ready, Alie?
- Mmm-hmm. All righty, here we go. I feel like I'm gonna barf. [Michael]<i>
Alie already seems scared.</i> <i> But is she just
afraid in general?</i> <i> Or is she more afraid
of the purple square?</i> <i> Which shape
is making her sweat the most?</i> - That's it?
- You're all done. The shock fairy
did not come to visit me? The shock fairy did not
come to visit you. [laughing]
So much adrenaline
for no pain. My hands are sweating so much
that the dye on my pants
is, like, on my hands now. [Michael]<i>
So which shape
scared Alie more?</i> <i> Despite receiving
no adverse stimuli,</i> <i> but after observing</i> my<i> fear,</i> <i> she had a higher
physiological response
to the purple square</i> <i> than the green circle.</i> You were definitely
more afraid of that purple square
throughout the experiment. Ahh. You know,
I'm not a gambler, but I think I was thinking, "I haven't gotten shocked yet--
it's coming." People are always saying
that they learn from me, but it's usually, you know, math or science
or facts in general. You learned<i> fear.</i> I still hate
that purple square. You're welcome. [laughing] Let's organize
what we've learned so far. Fear is a feeling
that we learn to have in response to things
our amygdala figures we would do best to avoid because in one way or another,
they could lead to our demise. Strands of fear-silk
have connected them in some way to possible death. Now, from talking with experts,
in my estimation, there are eight
unique innate aversions selected to engender panic
in us, by evolution, over millions of years. They come pre-learned
in our DNA, and include pain, isolation, the unknown or abnormal, disease, sudden movement, suffocation, falling, and incapacitation. These form the inner ring
of the web of fear. All our fears,
from rats to radiation, are based on connections
made by our amygdalae to death through one or more
of these innate aversions. When it comes to learned fears, there may be no limit
to the number we can acquire. As long as your amygdala
keeps spinning its threads, the web can extend forever. But here's what's even cooler: when our learned fears
are combined just right, they can be scarier
than the sum of their parts. Researchers have found
that if you've been conditioned to fear two separate stimuli, say, a purple square
and a green circle, seeing them suddenly together
makes you expect a worse outcome than seeing either stimulus
individually. - [Sidney screams]
-<i> Horror filmmakers</i> <i> take advantage
of this phenomenon</i> <i> by employing a technique</i> <i> called
Category Jamming,</i> <i> mashing several
categories of
fears together</i> <i> to create
the scariest
villains possible.</i> [Dr. Asma]<i> There's people
like Freddy Kreuger,</i> where you've got many things
that indicate death and fear, <i> like, you know,
the mottled flesh of his skin,</i> <i> the burn, he's a ghost,</i> <i> his hands are blades
of some kind.</i> <i> You're weaving together
a number</i> <i> of very fearful associations
that most people have.</i> <i> - And his criminal past.
- Right. All that together.</i> <i> Exactly.</i> [squishy sounds,
whiplash sounds] If you look at, sort of,
the<i> Alien</i> franchise, you'll
see that the face hugger <i> that grabs onto your
face is a beautiful hybrid
of a spider and a snake.</i> <i> Those are two things
that are universally feared,</i> <i> and so this is
a kind of category jamming.</i> <i> It doesn't fit in
our categories.</i> The designers
basically put them together so the fear
is amplified tremendously. Another example could be
just taking something that ordinarily
would never be here
and putting it there. If you put snakes
on a plane, <i> you've got something
most people are afraid of--
snakes--</i> <i> you've got flying,
which people are afraid of.</i> <i> You've also got
strange domain crossing.</i> Why would snakes be on a plane?
That doesn't make sense. And that's unsettling
in and of itself. So you're weaving together
a number of very fearful
associations that most people have,
and that's uniquely disturbing,
I think. So maybe<i> extreme</i>
category jamming, combining every
innate aversion
and conditioned fear, could be the scariest thing. It would certainly be likely to
catch anyone in a web of fear. Let's try it out. Now, conveniently,
I'm already in a graveyard, so we already have
the fear of death, decay... <i> [church bells tolling]</i> ...it's dark, I'm alone. Let's add in
some scary sounds... <i> [wolf howling]</i> [growling] ...a distorted human form, sudden movement... a mortal threat... gore... [creature growling] story and context... [growling] [growls] ...incapacitation. Is this it? Is the scariest thing possible just a combination
of every innate aversion and conditioned fear? [laughing] Oh, dear, Michael. Conditioned fears
know no bounds. So the scariest thing
is that the human mind can be made afraid of<i> anything!</i> [laughs evilly] No! Noooo! [Michael 3] <i>
Hold it!</i> Both of you, stop. Just-- Let's take a step back. Category jamming together
every possible learned fear and every innate aversion just sounds like a cop-out. I don't like that.
I want to be more specific. But this idea that
the scariest thing is the fact that
the human mind can be made afraid
of anything-- I don't like that, either. I mean, it might be
the scariest thing possible... but it also might not. What about people
who don't have an amygdala? Meet Patient SM. <i> Not the snake, the hands.</i> <i> This is all we are allowed
to show you.</i> <i> Her amygdala was destroyed
at the age of ten</i> <i> due to an incredibly rare
genetic disorder.</i> And because she doesn't
have an amygdala, she cannot learn to register
experiences as threats, which puts her life in danger, and that's why
we can't reveal her identity. Patient SM's feelings,
the feeling states, her subjective states,
seem to be absent in Patient SM. For example,
when she was walking
through a park one night, a guy came up to her
and put a knife to her throat, saying, "Give me your money." And she just kind
of ignored them and said, "Well, if you cut me,
I'll chase you down
and kill you." She was just<i>
all</i> rational. Yeah, yeah.
And she apparently
kind of knows that this isn't right, but she reacts
in a different way. Researchers have even
purposefully exposed her to classically scary things,
like spiders and snakes and haunted houses
and horror films, and she has exhibited
no fear response to any of them whatsoever. For a long time, scientists
considered SM living proof that without an amygdala,
we are unable to feel fear. But then... one experiment
changed everything. Scientists have known
for decades that a lack of oxygen
will make you feel dizzy, and maybe even euphoric,
before you pass out. But elevated levels
of carbon dioxide in the blood induce fear, anxiety, and panic. Patient SM volunteered
to inhale concentrated CO2. Her brain interpreted
the elevated levels of CO2
in her blood as proof that
she was suffocating, <i> a process
we are innately averse to.</i> <i> As usual, the researchers
expected SM to feel no fear.</i> But for the first time
in her adult life, <i> she felt sheer and utter panic.</i> The great thing
about that study on SM is really it was the first time that we showed that
these emotional responses can occur without an amygdala. Over the course
of the next year, the scientists tracked down
two rare patients in Germany who also had
non-functioning amygdalae and gave them the same
CO2 inhalation test. They had
the same panic response. <i> Researchers believe</i> <i> that the fight-or-flight
responses they observed</i> <i> in these amygdala-damaged
patients</i> <i> were induced by
CO2-sensing neurons</i> <i> in evolutionarily older regions
of the brain,</i> <i> like the midbrain
or even the brain stem,</i> <i> which control more primal
physiological functions.</i> <i> And so if I want to terrify</i> even the neurologically
un-scare-able, I need our body's
internal fear response to elevated carbon dioxide
levels in the blood. But the story doesn't end there. SM's researchers
later discovered
something even weirder. <i> When a control group
of people with functioning
amygdalae inhaled CO2,</i> <i> they showed a lower
fear reaction than Patient SM.</i> Why? Well, this question
led to a potentially
revolutionary rethinking of the amygdala's role in fear. Researches still believe
that the amygdala learns
to detect threats <i> that are outside the body</i> <i> so that the body
can respond to them,</i> <i> but when it comes
to</i> internal<i> threats,</i> <i> it may actually inhibit
your fear response.</i> <i> The control subjects
knew they were participating</i> <i> in a safe,
voluntary experiment,</i> <i> so their amygdalae
may have effectively told
other parts of their brain,</i> "Hey, relax.
Things are bad in the body, "but I don't detect
a real external threat,
so, like, calm down. A panic response
isn't gonna help;
not warranted." So if you want to ensure
the utmost amount of panic
in the most people, you don't need to category jam every possible scary
and unpleasant thing together, you only need two of them. Increase a person's
blood CO2 levels and present an external threat
they'll believe is causing it. Drowning. Waterboarding. Coerced CO2 inhalation. They're all variations
of the one true scariest thing: <i> elevation of carbon dioxide
in the blood</i> <i> caused by an uncontrollable
external threat.</i> [snickers] Sweet dreams. And as always... thanks for watching. ♪ Every single episode
of<i> Mind Field</i> ever made is free to view right now
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