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ROBERT KRULWICH: Hello again. Gaze into a
mirror, and what do you see? Well, I see my
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face, of course. But in my face I see moods,
I see shifts of feeling.
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We humans are really good at reading faces
and bodies. 'Cause if I can look at you and
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feel what you're feeling, I can learn from
you, connect to you, I can love you. Empathy
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is one of our finer traits, and when it happens
it happens so easily, perhaps becauseóand
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this is brand new science, this is just out
of the labówe may have some special circuitry
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in our brains that helps us whenever we look
at each other.
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Ask yourself, "Why do people get so involved,
so deeply, deeply involved, with such anguish,
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such pain, such nail biting tension over football?"
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COMMENTATOR: The Cleveland Browns are gambling
on defense.
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ROBERT KRULWICH: Why are we such suckers for
sports? And it's not just sports. We can lose
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it completely at the movies, at video games,
watching a dance. Is there something about
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humans, humans particularly, that allows us
to connect so deeply when we watch other peopleówatch
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them moving, watch them playing, watch their
faces?
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Well, as it happens, scientists have an explanation
for this strange ability to connect. It's
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new.
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DANIEL GLASER: It had never been found on
a cellular level before.
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ROBERT KRULWICH: A set of brain cells, found
on either side of the head, among all the
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billions of long branching cells in our brain,
these so-called "mirror neurons," have surprising
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power.
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DANIEL GLASER: What we've found is the mechanism
that underlies something which is absolutely
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fundamental to the way that we see other people
in the world.
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ROBERT KRULWICH: And it began entirely by
accident, at a laboratory in the lovely old
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city of Parma, Italy, where a group of brain
researchers was working with monkeys, and
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they were testing a neuronóthat's a brain
cellóthat always fired...made this sound...
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(NEURON FIRING): Clack, clack, clack.
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ROBERT KRULWICH: ...whenever the monkey would
grab for a peanut. So the lab had all these
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peanuts around, and whenever the monkey made
its move...
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(NEURON FIRING): Clack, clack, clack.
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ROBERT KRULWICH: ...the neuron would fire.
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Scientists thought, "Now here's a neuron that's
essential to motion. It's a motor neuron."
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Then, one day, the monkey was just sitting
around, not moving at all, just sitting, when
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a human scientist came into the lab. And when
that scientist grasped the peanut? Yeah, the
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monkey's cell fired.
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Now, the monkey hadn't moved, it was the human
that had moved, suggesting that this neuron
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up here couldn't tell the difference between
seeing something and doing somethingóseeing
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and doing were the sameóor more intriguingly,
that for this neuron, watching somebody do
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something is just like doing it yourself.
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The head of the lab, Giacomo Rizzolatti, thought,
"Wow!"
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GIACOMO RIZZOLATTI (University of Parma):
The same neurons, one neuron, fired, both
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when the monkey observed something, and when
the monkey is doing something. It is almost
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unbelievable.
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DANIEL GLASER: It was surprising, because
this cell, which was involved with motor planning
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for the monkey, turned out to be interested
in the movements of other people as well.
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ROBERT KRULWICH: Some people call them "monkey
see, monkey do" neurons, but the name that
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stuck is "mirror neurons," because with them,
the brain seems to mirror the movements it
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sees.
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This accidental discovery got scientists thinking,
doing more tests, and soon it came pretty
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clear that this is not just a monkey thing,
it's a people thing, too.
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We all know that humans learn by looking and
copying; that's what infants do.
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First you look...
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MOTHER: One, two, three, four.
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ROBERT KRULWICH: ...then you do.
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DONNA: Ready? Let's see your feet this way.
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ROBERT KRULWICH: And once you've watched and
copied and learned a set of moves, you not
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only have them in your head, if you see somebody
else doing it you can share the experience.
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They know the moves, you know the moves, so
you can move with them.
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DANIEL GLASER: If you can use the years of
training that you, yourself, have doneólearning
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to crawl, then learning to walk, then learning
to eatóthis is an incredibly rich set of
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knowledge that you could apply to the problem
of actually seeing what's going on.
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ROBERT KRULWICH: So that's why, when I head
down the street carrying all these packages,
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not only do people watch, look how they're
watching.
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They feel my predicament because they know
what it's like to carry heavy packages. They
-
know all about "carrying." So as they watch
me moving they can feel themselves moving.
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Their neurons are "mirroring" the action.
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These neurons may be the brain's way of translating
what we see so we can relate to the world.
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DANIEL GLASER: The mirror system is the way
that you tap into...the way that you harness
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your own abilities and project them out into
the world.
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ROBERT KRULWICH: And people are really good
at watching and translating what we see. Like,
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with just thirteen moving dotsóthat's all
there are hereóyou'll have no trouble recognizing
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these very ordinary activities. What's more,
tests have shown that when a person sees a
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movie like this of his own movement, he'll
recognize it immediately as his own.
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And that's why sports fans tense with the
action, and wince, and leap. 'Cause if you
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know the game...
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FOOTBALL FAN 1: Flag! Flag!
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FOOTBALL FAN 2: No, no, no flag.
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FOOTBALL FAN: No flag.
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ROBERT KRULWICH: ...then your neurons are
firing as if it's you playing, giving whole
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new meaning to the phrase "armchair quarterback."
That's why it's so easy to be a sports fan.
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But there is more, suggests U.C.L.A. professor
Marco Iacoboni. He thinks mirror neurons tie
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us, not just to other people's actions, but
to other people's feelings.
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MARCO IACOBONI (University of California,
Los Angeles): So the idea was to try to figure
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out how the emotional system and this motor
system are connected together.
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We're going to go in the scanner and what
you're going to do is to...
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ROBERT KRULWICH: To demonstrate, he put me
into this very powerful f.M.R.I. brain scanner
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that can peer into the brain while it's working.
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And he gave me some goggles so he could show
me pictures when I was in there.
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MARCO IACOBONI: So you can see here the eyeball
of Robert.
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ROBERT KRULWICH: And once he had a good view
into my brain...
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MARCO IACOBONI: Nice looking brain.
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ROBERT KRULWICH: Thank you.
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MARCO IACOBONI: Robert, you're not supposed
to talk when we scan you, all right?
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ROBERT KRULWICH: Sorry.
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Then he said, "Okay, I'm going to show you
a bunch of faces. And for each face, I want
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you to imitate it."
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So I did that. Then he recorded my brain while
I moved my facial muscles.
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MARCO IACOBONI: We're going do, right away,
another one.
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ROBERT KRULWICH: Okay.
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Then he said "Okay, same faces, but this time,
don't move a muscle, just look." So I looked.
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When we checked the results...
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Oh, there's my brain. I've never seen my brain
before.
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MARCO IACOBONI: This is your mirror area.
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ROBERT KRULWICH: Iacoboni says that the part
of my brain that's working when I make a face,
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the same part gets busy when I see the face.
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Plus, when I was looking at these faces, I
remember feeling extra uncomfortable, kind
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of bad. But when these faces came on, I felt,
I don't know, I felt better, almost happy.
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And, in fact, at that moment I was looking
at the happy face, my brainóand this is my
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brain at that instantósee that red area here,
it shows activity in the "happy" emotional
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part of my brain.
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And when I was imitating "happy" faces, look.
I get an even bigger response.
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This, says Iacoboni, is a consistent result.
Mirror neurons, he believes, can send messages
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to the limbic, or emotional system in our
brains. So it's possible these neurons help
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us tune in to each others' feelings. That's
empathy.
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MARCO IACOBONI: We strongly believe that that's
a unifying mechanism that allows people to
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actually connect at a very simple level.
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ROBERT KRULWICH: You are saying that there's
a place in my brain, which...whose job it
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is to live in other people's minds, live in
other people's bodies?
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MARCO IACOBONI: That's right.
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HELEN HAYES in A FAREWELL TO ARMS: Oh, darling,
I'm going to die! Don't let me die!
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GARY COOPER in A FAREWELL TO ARMS: Kat!
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ROBERT KRULWICH: And great actors instinctively
know that if they put feeling and drama into
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their bodies,...
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HELEN HAYES in A FAREWELL TO ARMS: Hold me
tight! Don't let me go!
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ROBERT KRULWICH: ...their faces, we will respond.
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GARY COOPER in A FAREWELL TO ARMS: You can't
die. You're too brave to die!
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DANIEL GLASER: What actors are experts in
is using their movements to inspire feelings
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in the people watching. These are the experts
in the mirror system.
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V.S. RAMACHANDRAN (University of California,
San Diego): We are intensely social creatures.
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We literally read other people's minds. I
don't mean anything psychic like telepathy,
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but you can adopt another person's point of
view.
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LINDSAY SCHENK (University of California,
San Diego): When you put it together, what
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do you think it's going to be?
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ROBERT KRULWICH: So if mirror neurons help
us connect emotionally, what about people
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who have trouble with this? Kids like Christian,
who has autism?
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LINDSAY SCHENK: Why do you like LEGOÆs?
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V.S. RAMACHANDRAN: It's been known for some
time that children with autism could be quite
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intelligent, but have a profound deficit in
social interaction.
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ROBERT KRULWICH: Christian can speak and read
and write, but like many kids with autism,
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he will avoid eye contact, he often misunderstands
questions.
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LINDSAY SCHENK: So, Christian, can you tell
me what you did in school today?
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CHRISTIAN: Doing well.
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LINDSAY SCHENK: You're doing well?
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CHRISTIAN: Mmhmm.
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ROBERT KRULWICH: Everybody wants to know what
exactly causes this. So Dr. Ramachandran and
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his graduate student, Lindsay Schenk, designed
an experiment...
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LINDSAY SCHENK: So we're going be reading
your brainwaves with this cap.
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ROBERT KRULWICH: They recorded brainwaves
while the kids opened and closed their hands
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and while they looked at a movie of somebody
else's hands. For most people, the brainwave
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looks the same either way, whether they're
doing or seeing. But for the kids with autism,
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the wave changes, suggesting, possibly, that
autism might have something to do with broken
-
mirror neurons.
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V.S. RAMACHANDRAN: Their brains may indeed
be different in that regard, and they may
-
have deficits in their mirror neuron system.
But we don't know this for sure yet. There
-
needs to be...additional work needs to be
done using brain imaging.
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ROBERT KRULWICH: But what we do know, says
Ramachandran, is that healthy human beings
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are intensely social. More than our cousins,
the monkeys, we invent ways to connect. We
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invent dances, and handshakes, and games to
play. We eat together. We meet and we talk.
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We talk a lot.
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V.S. RAMACHANDRAN: Everybody's interested
in this question: "What makes humans unique?"
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What makes us different from the great apes,
for example? You can say humorówe're the
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laughing bipedólanguage certainly, okay?
But another thing is culture. And a lot of
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culture comes from imitation, watching your
teachers do something.
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ROBERT KRULWICH: And here V.S. Ramachandran
makes a big leap. He has proposed that at
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a key moment in our evolution, this is his
guess, our mirror neurons got better. And
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that made all the difference, he says, because
once we humans got better at learning from
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each otherólooking, copying, teachingówe
could do things the other creatures couldn't.
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V.S. RAMACHANDRAN: In other words, if you
are a bear, and suddenly the environment turns
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cold, you need a few million years to develop
polar bear type layers of fat and fur.
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ROBERT KRULWICH: It would take many, many,
many bear generations to select for furrier
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bears. But, says Ramachandran...
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V.S. RAMACHANDRAN: If you're a human, you
watch your father slaying another bear and
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putting on a fur coat, you know, skinning
it, using that as a coat. You watch it, you
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learn it instantly. Your mirror neurons start
firing away in your brain, and you've performed
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the same sequence, complicated sequence. Instead
of going through millions of years of evolution,
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you've done it in one generation.
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ROBERT KRULWICH: And while no one is claiming
that mirror neurons are the key ingredient
-
that makes us different from other creatures,
what these neurons do suggest about us seems
-
almost self-evident. You can see it any Sunday
at a sports bar, that deep in our architecture,
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down in our cells, we are built to be together.
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DANIEL GLASER: There'd be very little point
in having a mirror system if you lived on
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your own. There'd be a lot of point in having
a digestive system if you lived on your own.
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There'd be a good point in having a movement
system if you lived on your own. There'd be
-
a good point in having a visual system if
you lived on your own. But there'd be no point
-
in having a mirror system. The mirror system
is probably the most basic social brain system.
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It's a brain system which there's no point
in having if you don't want to interact or
-
relate to other people.
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ROBERT KRULWICH: But we do like to interact.
And maybe now, as never before, we will understand
-
why. Okay, now, before we leave this subject,
we've designed a little mirror neuron exercise.
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What we're going to do is take a wishbone,
an ordinary wishbone, the kind you break for
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good luck, and we're going to take itócome
onóand we're going to take it for a stroll.
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And, if your mirror neurons are working properly,
when you see anything, even a wishbone walking,
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you know, along, you won't just watch that
bone, you are going to be that bone.
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The walking bone was created and designed
by artist Arthur Ganson, and later in the
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program we will show you a host of Ganson
gadgets in glorious motion.