- It is an odd sight. A middle-aged man, fully reclined,
drawing pictures of hammers and mugs and animal figurines on a special
clipboard, which is balanced precariously on a pillow atop his ample stomach.
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- A half-dozen people buzz around him. One adjusts a towel
under his neck to make him more comfortable, another wields a stopwatch
and chants instructions to start doing this or stop doing that, and yet
another translates everything into Turkish. A small group convenes in a
corner to assess the proceedings. A few of us just stand around watching,
and trying not to get in the way. The elaborate ritual is a practice run
for an upcoming brain scan and the researchers want to get everything just
right. Meanwhile, the man at the centre of all this attention, a blind
painter, cracks jokes that keep everyone tittering.
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- The painter is Esref Armagan. And he is here in Boston
to see if a peek inside his brain can explain how a man who has never seen
can paint pictures that the sighted easily recognise - and even admire.
He paints houses and mountains and lakes and faces and butterflies, but
he's never seen any of these things. He depicts colour, shadow and perspective,
but it is not clear how he could have witnessed these things either. How
does he do it?
-
- Because if Armagan can represent images in the same way
a sighted person can, it raises big questions not only about how our brains
construct mental images, but also about the role those images play in seeing.
Do we build up mental images using just our eyes or do other senses contribute
too? How much can congenitally blind people really understand about space
and the layout of objects within it? How much "seeing" does a
blind person actually do?
-
- Armagan was born 51 years ago in one of Istanbul's poorer
neighbourhoods. One of his eyes failed to develop beyond a rudimentary
bud, the other is stunted and scarred. It is impossible to know if he had
some vision as an infant, but he certainly never saw normally and his brain
detects no light now. Few of the children in his neighbourhood were formally
educated, and like them, he spent his early years playing in the streets.
But Armagan's blindness isolated him, and to pass the time, he turned to
drawing. At first he just scratched in the dirt. But by age 6 he was using
pencil and paper. At 18 he started painting with his fingers, first on
paper, then on canvas with oils. At age 42 he discovered fast-drying acrylics.
-
- His paintings are disarmingly realistic. And his skills
are formidable. "I have tested blind people for decades," says
John Kennedy, a psychologist at the University of Toronto, "and I
have never seen a performance like his." Kennedy's first opportunity
to meet and test Armagan in person was during a visit to New York last
May, for a forum organised by a group called Art Education for the Blind.
Armagan, who is something of a celebrity in Turkey, has become used to
touring with his canvases to the Czech Republic, China, Italy and the Netherlands.
What made this visit different was the interest shown by scientists - both
Kennedy and a team from Boston.
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- Kennedy put Armagan through a battery of tests. For instance,
he presented him with solid objects that he could feel - a cube, a cone
and a ball all in a row (dubbed the "three mountains task") -
and asked him to draw them. He then asked him to draw them as though he
was perched elsewhere at the table, across from himself, then to his right
and left and hovering overhead. Kennedy asked him to draw two rows of glasses,
stretching off into the distance. Representing this kind of perspective
is tough even for a sighted person. And when he asked him to draw a cube,
and then to rotate it to the left, and then further to the left, Armagan
drew a scene with all three cubes. Astonishingly, he drew it in three-point
perspective - showing a perfect grasp of how horizontal and vertical lines
converge at imaginary points in the distance. "My breath was taken
away," Kennedy says.
-
- Kennedy has spent much of his career exploring art from
the perspective of blind people. He has shown that people who are congenitally
blind understand outline drawings when they feel them just as seeing people
do. They understand and can draw in three dimensions. In fact, blind children
develop the ability to draw, he has found, much as sighted children do
- but all too few blind children ever get the opportunity to explore this
ability. Even knowledge about perspective, he has come to believe, is acquired
in similar ways for both. "Where a sighted person looks out, a blind
person reaches out, and they will discover the same things," says
Kennedy. "The geometry of direction is common to vision and touch."
Lines and one-liners
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- It is the night before the Boston team's first brain
scan. Armagan is sitting at a long table at an inn, entertaining everyone
with one-liners, trying to explain how he does his artwork. Alvaro Pascual-Leone,
the Harvard neurologist who invited him here, and Amir Amedi, his colleague,
are challenging him with more and more complex tasks. Draw a road leading
away, says Pascual-Leone, with poles on either side and with a source of
light underneath. Armagan smiles confidently.
-
- He uses a special rubberised tablet, called a "Sewell
raised line drawing kit". This device allows him to draw lines that
rise off his paper as tiny puckers, so that he can detect them with his
fingertips. And so he draws the road and the poles: one hand holding the
pencil, the other tracing along behind, like surrogate eyes, "observing"
the image as it is being laid down. A minute or so later, the picture is
done. Pascual-Leone and Amedi shake their heads in wonder.
-
- So, we ask, how do you know how long these poles should
be as they recede? I was taught, he says. Not by any formal teacher, but
by casual comments by friends and acquaintances. How do you know about
shadows? He learned that too. He confides that for a long time he figured
that if an object was red, its shadow would be red too. "But I was
told it wasn't," he says. But how do you know about red? He knows
that there's an important visual quality to seen objects called "colour"
and that it varies from object to object. He's memorised what has what
colour and even which ones clash. Scanning the mind's eye
-
- Next day, and the time has come for Armagan to get into
the scanner. The Harvard scientists are collaborating with scanning experts
at Boston University. In addition to taking a structural snapshot of Armagan's
brain and establishing if it can perceive any light (they confirmed it
cannot), this morning's experiment will have him doing some odd sequences
of tasks. He'll have a set number of seconds to feel an object, imagine
it and draw it. But he has also been asked to scribble, pretend to feel
an object and recall a list of objects that he learned days earlier.
-
- Pascual-Leone and Amedi want to see what Armagan's brain
can tell them about neural plasticity. Both scientists have evidence that
in the absence of vision, the "visual" cortex - the part of the
brain that makes sense of the information coming from our eyes - does not
lie idle. Pascual-Leone has found that proficient Braille readers recruit
this area for touch. Amedi, along with Ehud Zohary at the Hebrew University
in Jerusalem, found that the area is also activated in verbal memory tasks.
-
- When Amedi analysed the results, however, he found that
Armagan's visual cortex lit up during the drawing task, but hardly at all
for the verbal recall. Amedi was startled by this. "To get such extraordinary
plasticity for [drawing] and zero for verbal memory and language - it was
such a strong result," he says. He suspects that, to a certain extent,
how the unused visual areas are deployed depends on who you are and what
you need from your brain.
-
- Even more intriguing was the way in which drawing activated
Armagan's visual cortex. It is now well established that when sighted people
try to imagine things - faces, scenes, colours, items they've just looked
at - they engage the same parts of their visual cortex that they use to
see, only to a much lesser degree. Creating these mental images is a lot
like seeing, only less powerful. When Armagan imagined items he had touched,
parts of his visual cortex, too, were mildly activated. But when he drew,
his visual cortex lit up as though he was seeing. In fact, says Pascual-Leone,
a naive viewer of his scan might assume Armagan really could see.
-
- That result cracks open another big nut: what is "seeing"
exactly? Even without the ability to detect light, Armagan is coming incredibly
close to it, admits Pascual-Leone. We can't know what is actually being
generated in his brain. "But whatever that thing in his mind is, he
is able to transfer it to paper so that I unequivocally know it's the same
object he just felt," says Pascual-Leone.
-
- In his own life, too, Armagan seems to have a remarkable
grasp of space. He seldom gets lost, says his manager Joan Eroncel. He
has an uncanny sense of a room's dimensions. He once drew the layout of
an apartment he had only visited briefly, she says, and remembered it perfectly
nine years later.
-
- We normally think of seeing as the taking in of objective
reality through our eyes. But is it? How much of what we think of as seeing
really comes from without, and how much from within? The visual cortex
may have a much more important role than we realise in creating expectations
for what we are about to see, says Pascual-Leone. "Seeing is only
possible when you know what you're going to see," he says. Perhaps
in Armagan the expectation part is operational, but there is simply no
data coming in visually.
-
- Conventional wisdom suggests that a person can't have
a "mind's eye" without ever having had vision. But Pascual-Leone
thinks Armagan must have one. The researcher has long argued that you could
arrive at the same mental picture via different senses. In fact he thinks
we all do this all the time, integrating all the sensations of an object
into our mental picture of it. "When we see a cup," he says,
"we're also feeling with our mind's hand. Seeing is as much touching
as it is seeing." But because vision is so overwhelming, we are unaware
of that, he says. But in Armagan, significantly, that is not the case.
-
- I sit across from the source of all this mystery and
I ask him about the birds he loves to paint. They are brightly coloured
and exotic and I wonder aloud how he knows how to depict them. He tells
me about how he used to own a parakeet shop. "They come to your hand,"
he says. "You can easily touch them." He pauses and smiles and
says: "I love being surrounded by beauty."
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