Seeing a New Way Forward
One summer, my research team asked more than 1,400 men and women from sixteen countries which one of their five senses they would least like to lose. Which would be the most difficult to live without if it were taken away? Regardless of where they were from, their age, or their gender, seven out of every ten people said that losing their sense of sight would be the worst. The majority thought that they couldn’t live without vision. But actually, they could.
Let’s take a step back and make sure we’re on the same page with some of the fundamentals of vision science. We experience the sense of sight because of the connection our eyes have with our brains. We pick up on the brightness of the sun or register the hue of the sky with our eyes, but we only really experience seeing once our brains translate those sensations into something meaningful. Consider the following example. Linseed oil, mineral salts, bristle brushes, linen, and wood are products in their own right; but only when Claude Monet combined them in the right proportions and manner were we able to see the water lilies he painted outside his home in Giverny.
Alvaro Pascual-Leone is a neurologist at Harvard Medical School, and he’s famous for discovering what happens in our brains when we lose our sense of sight. He found that the visual cortex–the part of the brain at the back of our heads that specializes in making sense of the signals the eyes send it–is incredibly quick to retool when something changes in how our eyes operate. He invited people with normal vision to experience life without sight for five days. The volunteers wore blindfolds. These weren’t the kind you get in your travel kit when you fly internationally. They were high-tech and lined with photographic paper that would react to light exposure, so the researchers knew that none of the volunteers had seen the light of day (or bulb) since putting them on.
Pascual-Leone and his colleagues used the five days of blindness as an opportunity to teach basic Braille. The volunteers learned that the Braille alphabet is derived from bumps that protrude in various places on a two-by-three grid. The letter A feels like a dot popping up in the upper left corner of this grid. B feels like A but with the addition of the left-side dot in the middle row. The volunteers trained their index finger to feel the differences in where the bumps are and how many appear at once. By the end of the five days, they weren’t reading Shakespeare with their fingertips, but they had the basic alphabet down.
Each day, the researchers also invited the volunteers to lie down in an fMRI machine that would make a movie of what happened in their brains when they read Braille. On the first day, their brains were most active in the somatosensory cortex, the part of the brain responsible for what we touch and feel; their visual cortex did nothing in response to feeling the Braille letters. But by the end of the five days of having no sight, this pattern reversed: the somatosensory cortex responded less, and the visual cortex responded more, when the volunteers felt the Braille letters. In other words, the work their fingers were doing was now registering in the part of the brain that for its whole life had been responsible for actual seeing. In less than one week, the visual cortex adapted and repurposed itself to reflect what happens in the brains of truly blind people who are proficient in reading Braille–the visual centers in the brain registered what their fingers were “seeing.”
When Pascual-Leone blindfolded his volunteers, he was in a sense reinventing the process of perception. The brains of his volunteers still wanted to see, but they couldn’t do it with their eyes. He was changing their medium, but they were still artists. When the brushes are gone or can’t do the trick, an artist finds a new way to apply paint. Jackson Pollock dripped it from cans. Gerhard Richter crafted a squeegee to scrape across canvas. When Pascual-Leone usurped his volunteers’ sense of sight, they found a new way to see.
The amazing adaptability of vision that Pascual-Leone discovered through his volunteers’ experience is called neuroplasticity, and it’s a trick for which the visual cortex has gotten quite famous in the brain-science world. But there are more reasons to appreciate our sense of sight than its chameleon nature. Consider its strength. If we found ourselves in a place that was really dark and clear, without haze in the air, we could see a candle flickering thirty miles away with the naked eye. When we look into the night sky, we can easily see the International Space Station 250 miles up, or all the way to Saturn–about a billion miles off–if we know where to look.
And our eyes are speedy. They transfer data at the rate of about 8.75 megabits per second. That’s about three times the speed of the average Internet connection in the United States. We can recognize what’s in front of us faster than the speed of sound. And, though the taste of salt is starkly different from that of sugar, it takes our brain twice as long to register the difference in flavor than to distinguish the face of someone we like from that of someone we don’t. Indeed, scientists have discovered that it only takes 1⁄76 of a second to know we’re looking at the face of a friend, the car of our dreams, or the roses in our wedding bouquet.
What we see with our eyes feels real, accurate, and honest–so much so that it can be scary. In 1896, audiences saw moving images for the first time in history. French aficionados watched a short film called “L’arrivée d’un train en gare de La Ciotat” in a Paris cinema. The fifty-second black-and-white movie featured a train heading directly toward the viewer on its way into a coastal station. Though the audience sat in their seats and the film was a silent one, the image of the steam locomotive barreling closer was rumored to have led audience members to jump from their seats in terror.
We favor and intuitively trust our visual experiences, often over everything else. We believe that what we see is an accurate and complete representation of the world around us. But that’s not always the case. Take the example of the line drawing of an animal below. Give yourself about one second, but not more than that, to take a look. What is it? What’s your first impression?
Most people see the head of a horse or donkey. That’s what I see too. But look again, now for perhaps a bit longer. With this second glance, or from a changed perspective, you might see something quite different. A seal, perhaps? It’s possible that you saw the marine animal to begin with and then with my mention of the horse you looked back and tried to figure out if there was a typo in the text.
I have shown this image to hundreds of people, most recently to an auditorium in New York City’s Rubin Museum of Art full of patrons attending a lecture on the science and art of deception. I opened the conversation with this image, projected on a screen for one second. Then I polled the crowd, asking “Who saw the farm animal?” About 80 percent of arms shot up. At the same time, the remaining 20 percent started whispering, and the sound grew quickly to a din. I heard one older woman near the front, vintage eyeglasses pressed up hard against her eyes: “What is she talking about?!”
The group grew restless. The horse-seers turned in their seats, staring at the seal-seers, who swore there was no horse there. The seal-seers were audibly riled, certain that I, along with what must be the baited and staged audience, was pranking them. Everyone was certain that what they had seen was an artistic depiction, sure, but very obviously of whichever animal they themselves had seen first.
We have a blind faith in our visual experiences that we don’t hold for nearly any other source of information or inspiration. Though our reliance on and trust of our visual sense may occasionally lead us astray–as it did with my unsuspecting museum audience and with the Parisian audience unaccustomed to the sight of a train on the silver screen–visual perception is powerful.
All of this, combined, positions our eyes to be one of our greatest allies in the battle against ourselves as we work toward meeting our goals. Our eyes play a role in overcoming the mental hang-ups that plague our attempts to stay committed, the physical challenges that slow progress, and the constraints of reality that place a heavy burden on even getting started in the first place. When we tell ourselves we can’t do something, it might just be that we are seeing something as more challenging than it really is. When we say that what we’re up against is the impossible, it might not appear that way to someone else--and it doesn’t have to look that way to us. Just like the bespectacled woman in the front row of the museum auditorium eventually understood that the drawing could be of both a horse and a seal, any of us can teach ourselves to see the world differently if we understand how to take control of perception. Our eyes are incredible tools for shaping our experience. With them, we can quite literally see a new way forward.