A world of echoes: Canadian research into how the blind use sound to see
WATCH: 16×9’s “Second Sight”
I was walking with Brian Borowski down a residential street in London, Ontario, when he told me: “We’re coming up to a park.”
Brian is 59, and he’s been blind since birth. So I had to ask: “How do you know it’s a park?”
Easy, he explained. It sounded like a park.
“So what does a park sound like?” I asked. There were no children playing. No dogs barking. Nothing that “sounded” like park to me.
“Just listen,” he said. “There’s no sound coming back. That means an open space. On the other side of the street, I’m getting echoes from houses. On this side, nothing. Wide open. And there wouldn’t be an empty field in this part of the city.”
Brian has never seen a park. Or a tree. Or an open space. He has no sense of the colour green. But he has a concept in his mind for “park.” A restful, quiet place, where the air is fresh and there are no cars, or much to bump into. It’s not a picture in his mind (he doesn’t see pictures) but a spatial idea, confirmed by the fact that there are few or no echoes coming back.
Just to confirm his perception, Brian makes a clicking sound with his tongue, and moves his head back and forth, so his ears can pick up and analyze any echoes. There are none.
It is a simple but very effective demonstration of echolocation—navigating with sound.
But the question won’t go away. There is no light entering the brain of the sightless. What does a blind person see?
Here’s how Jim Davies of Carleton University’s Institute of Cognitive Science explains it:
“Your first guess might be . . . a vast blackness. But imagine telling a goose . . . that you can’t sense Earth’s magnetic field. The bird, baffled, asks, ‘So, what do you sense when you change the direction you’re facing?’ The answer, of course, is nothing. Just as blind people do not sense the color black, we do not sense anything at all in place of our lack of sensations for magnetic fields or ultraviolet light. We don’t know what we’re missing.”
Brian, who works as a computer programmer at Western University, has a number of tools to help him experience what he’s missing by not having eyes. He uses a white cane. And a pair of aging seeing-eye dogs. And an iPhone map that talks. But he seems most comfortable with echolocation—clicking with his tongue, or snapping his fingers, and processing the echoes. Like a bat. In fact, a Reader’s Digest profile on Brian was titled “Batman.”
A half-million Canadians have significant vision loss, and I would be surprised if many of them feel as comfortable and connected to the world as Brian does. Both he and his brother David were born blind, and as children they taught themselves to echolocate. At the school for the blind they attended, the two boys were discouraged from clicking. It was seen as stigmatizing, making them “stand out.” That attitude still seems to prevail among some institutions for the blind today. And Brian is conscious of it. If there are people around, he might snap his fingers or jingle coins in his pocket to produce an echoing sound, so as not to draw attention.
In that sense, Brian doesn’t have quite the bravado and effervescence of Daniel Kish, the Southern California man who has popularized echolocation around the world, with his in-your-face message that blindness is largely a social construction: The sightless, Kish says, are only limited by the expectations we have of them. We call them handicapped, we help them across streets, we offer them our arms and our sympathy, and in the process, “dependency conditioning” sets in, says Kish.
WATCH BELOW: An extended interview with Daniel Kish
At his workshops for blind students, Daniel enforces a “no helping” rule—the kids and adults learning echolocation have to fend for themselves. No helping hands across streets. No nudging in the right direction. They have to learn to be fearless—to risk bumping into a pole or a parked car. They have to allow the visual cortex in the brain to learn how to process the echoes of their clicks, and to use that radar to navigate. They have to open the door to neuroplasticity—the ability of the brain to change. Eventually, like Daniel, they may get brave and confident enough to ride a bike. (Daniel admits that is a challenge for many parents of blind kids—the willingness to “let go.”)
Both Daniel and Brian have worked with vision neuroscientist Mel Goodale, director of the Brain and Mind Institute at Western University in London, Ontario. Goodale put them both to work in his experiments to determine what happens inside the brain of people without vision who echolocate.
WATCH BELOW: Neuroscientist Mel Goodale, director of the Brain and Mind Institute at Western University in London, Ontario, conducted a number of echo-location experiments with Brian Borowski in an anechoic chamber at the university. The purpose was to determine the precision of echo-location.
And what he found was extraordinary: The part of the brain that normally processes light from the retina of the functioning eye—the visual cortex—plays an entirely different role for the blind echolocator. It actually draws information from the auditory signals—the echoes—that come back to the blind, and provides data about shape, size, texture and even direction of movement.
Goodale has learned a lot about the brain’s adaptation to echoes, but if you ask him point-blank what the blind actually “see” he admits he doesn’t know. All our perceptions, he says, are subjective.
Or as a philosopher might put it, to Brian Borowski, a “park” is not a sight. It’s an insight.
– With files from Mia Sheldon
16×9’s “Second Sight” airs this Saturday at 7pm.
BEHIND THE STORY: Producers Mia Sheldon and Claude Adams tell Laurie Few about the remarkable Daniel Kish– the blind California man who rides a bike—and about the cutting-edge Canadian research into how echolocation changes the brain.
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