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ALAN
ALDA Hello and welcome to Scientific American Frontiers. I'm Alan
Alda. For those millions of us whose vision or hearing isn't perfect,
there are glasses and hearing aids. But for those hundreds of thousands
who are blind or profoundly deaf, devices that merely assist the
eyes and ears just aren't enough. What they need are alternative
routes by which the sights and sounds of the world can enter the
brain and be interpreted. In tonight's program we'll see how the
astonishing success of what are in effect artificial ears is not
only changing the lives of many in the deaf community — especially
the young — but is also inspiring researchers tackling the
much larger challenge of artificial vision.
ALAN
ALDA (NARRATION) We'll see a young girl hear her first sounds from
a synthetic ear…
ALAN
ALDA What kind of a star do you want to be?
ALAN
ALDA (NARRATION) And catch up with her three years later.
KELLEY
FLYNN I want to be an actress.
ALAN
ALDA (NARRATION) And we'll meet a man whose artificial retina is
giving him the first glimmering of sight.
ALAN
ALDA That's my forehead. That's my forehead!
TERRY
BYLAND Well, it's very bright, I tell you.
ALAN
ALDA That's all coming up in tonight's episode, Cybersenses.
EVERY
SOUND A PRESENT
ALAN
ALDA (NARRATION) Three years ago we met Kelley Flynn, who lives
with her family near Northampton Massachusetts. Kelley was then
seven — and one of her favorite walks — then and
now — is through the woods to a nearby river.
KELLEY
FLYNN I love the river.
MARY
FLYNN Why?
KELLEY
FLYNN Because it is beautiful.
MARY
FLYNN Yeah. Can you hear it?
KELLEY
FLYNN A little.
MARY
FLYNN What about when you get your cochlear implant?
KELLEY
FLYNN When I get cochlear implant, I will hear the best.
ALAN
ALDA (NARRATION) Kelley had been profoundly deaf since she was two.
What little hearing she had -- boosted by a conventional hearing
aid — was worsening. She had no trouble communicating by
sign — but for years she'd wanted to talk.
MARY
FLYNN Do you like to sign or do you like to talk?
KELLEY
FLYNN I like to talk. That's why I want cochlear implant. To hear
better.
MARY
FLYNN To hear better. Why do you want to hear more?
KELLEY
FLYNN Because I would love to hear more. Because when you call me,
I will hear.
ALAN
ALDA (NARRATION) Tomorrow is the day Kelley has been waiting for
for months.
MARY
FLYNN You're gonna go in, in the room, in one minute. Mommy has
to change her clothes, and then I will go in there with you. Okay?
GARY
FLYNN It's just the beginning, but it's an exciting beginning. And
in a way, the beginning of her hearing in a whole new way which
is very exciting. And she's the most excited about it.
MARY
FLYNN Good girl, Kel. You're so brave.
ALAN
ALDA (NARRATION) The surgery that's about to begin on Kelley will
permanently implant a tiny set of electrodes deep within her inner
ear. MARY FLYNN Thank you.
ALAN
ALDA (NARRATION) In a normal ear, sound vibrations are translated
into nerve impulses by millions of tiny hair cells lining the inner
wall of the snail-shaped cochlea. Kelley went deaf when an infection
destroyed these delicate hairs. A cochlear implant substitutes an
array of tiny electrodes — 22 in Kelley's case —
for the hairs of the hair cells, directly stimulating the cells
to send their messages to the brain. Kelley's surgery is being done
at Boston's Children's Hospital by Dr Margaret Kenna.
MARGARET
KENNA What I'm doing now is drilling actually into the cochlear.
And the bone of the cochlear is very hard bone -- harder than the
rest of the bone in the rest of the body. And as you go towards
the center of the cochlear it gets very white. So now we have a
hole in the cochlear. Do you see it? ALAN ALDA Oh yeah, I see it
very clearly.
ALAN
ALDA (NARRATION) The electrode array being slipped into Kelley's
cochlea is attached to a receiver that is also implanted under the
scalp. Both the electrodes and the receiver are connected in turn
to an antenna and a magnet. The entire implanted system is visible
in an X-ray taken while Kelley is still in the operating room.
MARGARET
KENNA This is the antenna right here. This is the magnet. This is
the receiver stimulator right here. And this is the wires, the electrodes
in the cochlear. If you look even closely, you can almost count
each individual electrode.
ALAN
ALDA (NARRATION) It will take about two weeks for Kelley to recover
from her surgery.
MARILYN
NEAULT Hi. Are you ready?
KELLEY
FLYNN Yes.
MARILYN
NEAULT Good. What are we doing today?
KELLEY
FLYNN My cochlear implant will turn on.
MARILYN
NEAULT We're turning on your cochlear implant. Alright.
ALAN
ALDA (NARRATION) A wireless transmitter sticks to the magnet under
Kelley's scalp.
MARILYN
NEAULT Can you see it?
ALAN
ALDA (NARRATION) From now on, this is how sounds will get to her
brain — from the microphone behind her ear, via a computer
that will process the sound into the signals sent to her cochlea.
Right now, Kelley's microphone isn't on. These beeps are being fed
into her cochlea directly. The cochlea normally responds to high
frequency sounds at one end, low frequencies at the other. The electrodes
in the implant mimic this process. Kelley has been asked to put
a ring on the stick whenever she detects a sound.
GARY
FLYNN She told her friend that when she came back maybe she'd be
able to call her on the telephone. She's already exploring it in
her mind. She's imagining the things she might be able to do. And
her hearing, it's a gift now. It's not just being something you're
born with. It's something very special to her. It's like Christmas.
Each sound is a present.
ALAN
ALDA (NARRATION) So far today, Kelley has only heard the beeps generated
by Marilyn's computer. But now comes the moment Kelley has been
waiting for. Her microphone is switched on. Now sounds from the
room are able to enter her head.
MARY
FLYNN Do you like the way that sounds? Is it really really loud?
Is it really loud? Or is it perfect?
KELLEY
FLYNN It's perfect.
ALAN
ALDA (NARRATION) Kelley gets her own little computer to process
the sounds picked up by the microphone behind her ear into the signals
sent to her cochlea.
MARILYN
NEAULT I'll just put it there. And let the hair fall down over it.
ALAN ALDA (NARRATION) It's the sophistication of this processing
— especially for the sounds of speech — that has
in the last few years started to open up the hearing world to profoundly
deaf children.
ALAN
ALDA Hello. Hi. Hi.
ALAN
ALDA (NARRATION) To find out how -- and what lies ahead for Kelley
-- we're visiting a classroom for hearing impaired children -- where
my job is to read a story.
ALAN
ALDA "It isn't fair that my brother Anthony has two dollars and
three quarters and one dime and seven nickels and eighteen pennies."
ALAN
ALDA (NARRATION) The room is equipped with a sound system so that
the voice of teachers — or guests — is kept at
a constant level. Some of the children here have conventional hearing
aids. Several — including six-year-old Timmy —
have cochlear implants.
ALAN
ALDA Timmy, do you like money?
TIMMY
I like lots and lots of money.
ALAN
ALDA Lots and lots of money?
ALAN
ALDA (NARRATION) Those of us without cochlear implants can never
know exactly how they sound to children like Timmy, but here's a
guess.
ALAN
ALDA "So they brought lox because my father likes to eat lox, and
they brought plants because my mother likes to grow plants."
ALAN
ALDA (NARRATION) Like the children in the classroom, Kelley now
faced many hours of hard work, both to decipher the sounds created
by her cochlear implant and — even tougher — learning
how to speak herself, after years of having few clues as to how
her speech should sound. Meanwhile, she can finally hear her river.
Three years after her implant, we met with Kelley again, along with
Marilyn Neault, who first turned on her hearing.
ALAN
ALDA Do you remember the day we were filming and your cochlear implant
device got turned on for the first time?
KELLEY
FLYNN Yeah. ALAN ALDA What was that like?
KELLEY
FLYNN I wasn't camera shy at all. I felt like a star like I always
wanted to be.
ALAN
ALDA What kind of a star do you want to be?
KELLEY
FLYNN I want to be an actress.
ALAN
ALDA Yeah. Has Kelley already become a star from this program? Do
people know her, know her face and everything?
MARILYN
NEAULT Well, for the first couple of years, and it's been three
years now, you would come and sit in our waiting room, waiting for
an appointment with me, and families would come up to you and say,
"You're the girl who was on the Alan Alda show, you were on Scientific
American Frontiers. And they would tell you and your parents that
the show had a big effect on them, it gave them confidence to get
a cochlear implant for their child.
ALAN
ALDA That's really great. You know what's great, better than being
a star is being able to help people like that. I think that's terrific.
How young can a child be and get a cochlear implant?
MARILYN
NEAULT That's an interesting question. The Food and Drug Administration
approves cochlear implantation beginning at age 12 months. ALAN
ALDA What difference does that have on their ability to speak?
MARILYN
NEAULT We used to be thrilled if a deaf child developed six month's
worth of language in a year's time. And now we see them develop
a year's worth of language in a year's time, or sometimes more.
And we see two- and three-year-olds who have had their implant for
a year or two who have spoken language development that's really
within the normal range. They don't have to be behind any more.
It's changed everything.
ALAN
ALDA Does Kelley speak differently now that she has the cochlear
implant?
GARY
FLYNN I can remember after the implant, picking her up at Clark
School probably six months after the implant, and she had gone on
a field trip to Plymouth. And I was always very familiar —
I shouldn't say this — driving with my knee and signing
to her in the car and then getting that from her. This time it was
dark and suddenly we were talking about — talking —
about the field trip. And it was, it was….kind of gives me
goose bumps now because it was a conversation in a way we never
could have had before. ALAN ALDA Can you hear that plane?
KELLEY
FLYNN I hear lots of planes during softball. And when my coach is
talking, when he's telling us what you do, I keep hearing planes
go by. Like yesterday, yeah, and all I could see…….like
there's a bee in their mouth. ALAN ALDA Ah, that's good!
SECOND
SIGHT
ALAN
ALDA (NARRATION) We're in Los Angeles, where Terry Byland —
who's been blind for the last eleven years — is about to
see again. It won't be much — at best a few fuzzy blobs.
But he and a team here at the University of Southern California
Medical Center are hoping he's taking the first steps toward a device
that could do in the future for the blind what the cochlear implant
can do today for the deaf. Terry has retinitis pigmentosa, one of
the main causes of blindness, affecting one in 4000 people. RP is
an inherited degenerative disease — and it robbed Terry
not only of his sight eleven years ago, but also, at the time, of
his spirit.
TERRY
That first couple of months was like hell for me. I didn't know
what to do with myself. I couldn't do anything, I was so negative.
And then I found out about the Braille Institute in Anaheim and
going there they taught me how to be the best blind person I could
be. So that's what I had to settle for. But now I realize, thanks
to all these wonderful people here, I don't have to settle for that
anymore.
ALAN
ALDA (NARRATION) Six months ago, Terry was on the operating table
for an eight-hour procedure performed by USC Medical Center's Mark
Humayun, who implanted into Terry's right eye a tiny array of 16
electrodes less than a quarter inch square. Today, he's back for
a routine check to make sure the electrodes are still sitting snugly
against the retina — which in Terry's eye has the characteristically
sooty appearance of retinitis pigmentosa. The electrode array is
connected by a thin wire that runs just under the skin of his temple
to a magnetic connector over his ear, very similar to the one used
by Kelley and other cochlear implant patients. A tiny video camera
transmits images to a computer, which processes the images and transmits
them wirelessly through the magnetic connector and on to the electrode
array. There the electrodes send the image in the form of electrical
impulses directly to the optical nerve. In effect the 16 electrodes
in the array function as a very crude, simplified substitute for
the millions of light-sensitive retinal cells that in Terry's eye
are damaged beyond repair.
ALAN
ALDA When each one of these electrodes is activated, he's going
to see either a dark spot or a light spot there? MARK HUMAYUN Well,
that's the very interesting and intriguing thing. It turns out that
when we activate one of these electrodes, it's very low current,
initially most patients see a black spot. But as you turn up the
current, that turns into a white spot. So the idea is to use each
of these much like a dot matrix printer or the lights of a scoreboard,
to light them to enable Terry to be able to recognize shapes.
ALAN
ALDA OK, I'm rally anxious to see what he sees.
ALAN
ALDA (NARRATION) The video camera that's will act as Terry's eye
is in the bridge of the glasses.
MARK
HUMAYUN OK, and I'll give you the connector here.
TERRY
BYLAND OK.
MARK
HUMAYUN Just to show that it's very easy for the patient to do this.
ALAN
ALDA (NARRATION) Today's test is to see if Terry can locate a light
square projected on to the wall. Because the video camera is in
his glasses, to move his field of vision he has to scan with his
head.
TERRY
BYLAND That would be upper left.
MARK
HUMAYUN OK, good. And what we do is we also time it.
ARUP
Ready Terry?
TERRY
BYLAND Yup. That would be lower left.
MARK
HUMAYUN Good, that's very good. Terry, you're getting very good
at this.
ALAN
ALDA What are you actually perceiving, Terry?
TERRY
BYLAND Well, it's a light light, and it's actually fuzzy looking,
and it kind of flickers… a white flickering fuzzy light, and
it's about this big around. After being blind for eleven years it's
so wonderful to be seeing any of this stuff. For some people who
have never lost their sight it may not be a big deal, but for us
it's just amazing.
ALAN
ALDA (NARRATION) Terry did well locating the squares. But now he
has to scan carefully so that the electrode array on his retina
will reveal if the bar is vertical or horizontal.
TERRY
BYLAND That's a vertical.
MARK
HUMAYUN Correct.
ALAN
ALDA Seven seconds. I don't mean to rush you. I get competitive
about this.
TERRY
BYLAND They're always telling me to slow down.
ALAN
ALDA (NARRATION) So far, Terry has only used the device in this
room, scanning images like these for a few hours at a time —
and it's still hard for him to figure them out.
TERRY
BYLAND That would be vertical again.
ALAN
ALDA (NARRATION) The computer screen allows us to see how the electrodes
are being activated as Terry scans the shapes.
ALAN
ALDA I think I know what it is now. Do you know what it is?
TERRY
BYLAND Looks like vertical again.
ALAN
ALDA To me too, yeah.
MARK
HUMAYUN OK, both of you are correct.
ALAN
ALDA Am I seeing it more clearly do you think than Terry is seeing
it? I mean, I'm seeing distinct dots, you know.
MARK
HUMAYUN That's an important feature, because there's going to be
some current spread from the electrodes. So the perceptions are
going to blend a little bit. So you're seeing it much, you're probably
seeing it clearer than what Terry sees.
ALAN
ALDA I see.
ALAN
ALDA (NARRATION) Not only do the nice clean dots we can see appear
much fuzzier to Terry, but the part of his brain receiving those
fuzzy images hasn't been getting input from his eyes for eleven
years now.
TERRY
BYLAND That'd be horizontal.
ALAN
ALDA See, I got you rushing.
MARK
HUMAYUN What you see is that there may be some reorganization, some
learning that needs to be done in an area that hasn't seen for a
while.
ALAN
ALDA You bring up a really good point. Because even though this
is more distinct than what Terry is seeing, I'm able to interpret
these dots more easily than probably Terry can without practice.
MARK
HUMAYUN If your arm has been in a sling and you haven't used it
for a while and someone asks you to write, your initial writing
is very different. ALAN ALDA Have you seen any objects in this setting
or have you only looked at these rectangles of light so far?
TERRY
BYLAND It's all been in this room so far, mostly of the light variety,
we haven't been outside yet.
ALAN
ALDA Because I'm wondering, if you see for the first time someone
you know, your wife or your child, even though they're just a blob,
I wonder what effect it will have on you?
TERRY
BYLAND It'll be wonderful, I'll tell you. It'll be really wonderful.
It's been a long time.
ALAN
ALDA (NARRATION) These goggles will give me a sense of the 16 pixel
world Terry might see once he leaves the testing room —
though my pixels are much sharper than the fuzzy blobs Terry reports
seeing.
ALAN
ALDA Let me spin around a little bit. Am I driving you crazy? Let's
see here, pretty dark. There's the camera, kind of dark. But I'm
just seeing squares of light and dark.
MARK
HUMAYUN Can you tell which way my hand moves?
ALAN
ALDA Left and right.
MARK
HUMAYUN Right. That's a tremendous improvement for somebody who
is completely blind, to be able to tell motion.
ALAN
ALDA (NARRATION) The next generation of the artificial retina will
have 64 pixels rather than 16.
MARK
HUMAYUN This is the generation we're talking about launching in
the middle of 2005.
ALAN
ALDA OK. Sort of a head and shoulder shape. Somebody just came in.
TERRY
BYLAND Can you see any movement over here Alan?
ALAN
ALDA Yes, yes, I can see on my upper left.
ALAN
ALDA (NARRATION) But the 64-pixel array is only the next step toward
what Mark Humayun hopes will be a system that goes far beyond being
able to provide glimpses of shapes and movement.
MARK
HUMAYUN This is going to be, we think, the significant jump.
ALAN
ALDA How many pixels will this be?
MARK
HUMAYUN This will be 32 by 32, or about 1024.
ALAN
ALDA Wow. Oh, oh my god. Terry, Terry, this is going to… you're
going to be amazed at this. Here's what I see. I see clearly head
and shoulders. I see the painting behind you. I see three squares
that are your nose, the shadow of your nose. I see two squares that
are our eyes. I see your cheeks. I actually see a face.
TERRY
BYLAND Oh my god.
ALAN
ALDA Let me see you smile. Can I see you smile? Yeah, I can't quite
pick up the smile. But a little it, a little bit. Yeah I think I
can. Oh god, Terry, you're going to love this.
ALAN
ALDA (NARRATION) One of the hopes for a 1000 electrode artificial
retina is that it will allow people to read — at least
large print.
ALAN
ALDA Wait. "The Retina Institute."
ALAN
ALDA (NARRATION) But remember, I'm using a only a simulation of
a thousand pixel array — and as we've seen from Terry's
testing, it's much harder for him to make sense of the fuzzy blobs
he sees than the perfect little squares projected into my eyes.
But for Terry and the thousands like him with incurable retinal
blindness, there is now hope for the first time.
ALAN
ALDA With practice, you're going to be able now in the next few
months with just 16 pixels to be able to sense things and see things
that you haven't been able to see before. When you get this…
this is amazing.
TERRY
BYLAND Oh it is. It's just going to get better and better, that's
why it's so exciting to be part of it even on a daily basis.
ALAN
ALDA (NARRATION) At the end of our visit to the USC Medical Center
we persuaded the researchers to let Terry try the system outside
for the first time. In the coming months, the plan is to let him
take it home and use it daily with the hope that he'll gradually
piece together a very primitive picture of the world around him.
ALAN
ALDA How about, if you look down, down to about there, from there
to there, do you see any difference in light?
TERRY
BYLAND Right there is shade. Up there is light.
ALAN
ALDA Right. Let me point…
ALAN
ALDA (NARRATION) In the eleven years since Terry lost his sight,
like many blind people he has learned to sense his environment from
other cues — especially sound, like that of the water behind
us.
ALAN
ALDA You're accustomed to listening to sounds and knowing how close
you are. And now you're adding light and dark. So I'm wondering
if…
TERRY
BYLAND That's real light right there.
ALAN
ALDA That's my forehead. That's my forehead!
TERRY
BYLAND Well, it's very bright, I tell you.
ALAN
ALDA That's great.
TERRY
BYLAND Very bright. Very bright. Oh god, this is beautiful, I tell
you.
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