If A Blind Man Can Suddenly See, Would He Be Able to Distinguish Objects by Sight Alone?

In 1688, Irish scientist William Molyneux asked philosopher John Locke "if a man born blind can feel the differences between shapes such as spheres and cubes, could he similarly distinguish those objects by sight if given the ability to see?"

That philosophical thought experiment, called Molyneux's Problem, stood for centuries until MIT researchers Richard Held and Pawan Sinha collaborated with Indian surgeons to operate to restore sight in children who'd been blind from curable causes:

Held, Sinha, and colleagues recruited five children, ages 8 to 17, from Project Prakash to tackle Molyneux's question. The researchers built 20 pairs of simple shapes from toy blocks and tested the children within 48 hours of the surgery to restore their sight. The children had not encountered these unusual shapes before. [...] After feeling a shape, the children did only slightly better than chance at identifying it by sight alone, the team reports online today in Nature Neuroscience.

That result suggests a negative answer to Molyneux's question. Because many children travel long distances for the operations, most go home with their families before the researchers can do follow-up experiments, Sinha says. However, when the researchers retested two of the boys with a new set of shapes a few days later, their accuracy on the touch-to-vision experiment jumped to above 80%. That suggests a more nuanced answer of "initially no but subsequently yes," Sinha says.

"It's a great story," says Alvaro Pascual-Leone, a neurologist and neuroscientist at Harvard Medical School in Boston. The change in the children's ability to integrate touch and vision happens too fast to be explained by major rewiring in the brain, Pascual-Leone says. Even though they grew up recognizing objects by touch, they needed only a little bit of visual experience to learn to translate between the two senses. "They're not starting from zero," he says.

Link (Photo: Pawan Sinha)


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Molyneaux's question dealt with something slightly (but significantly) different. Unlike the children in this experiment, Molyneaux's hypothetical person has been acquainted with these objects since birth (but, of course, by touch alone.) The question was whether or not this person, on receiving their sight, would be able to "..know which is the Globe and which the Cube" by sight alone - without any touch-acquaintance at the time of the test. Of the three tests given the children, only the third test approaches Molyneaux's sense modality question and that's where the childrens' performance plummeted. The article didn't say whether or not, during the third test, the children were able to touch-and-see the shape or just touch the shape before it was removed from them and they were required to use sight alone. ("After feeling a shape [feeling only?], the children did only slightly better than chance at identifying it by sight alone.") Does anyone know?
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Reminds me of an Iranian film I'm still trying to see. It is called "The Willow Tree" and it's about a man born congenitally blind. He learns his world through touch and becomes extremely fond of the willow tree. An operation restores his sight and he begins to evaluate the world according to how he sees. People he knows now have appearances, but with great costs, the man begins evaluating them on their beauty and his attitudes toward them change accordingly. What's worse, is he now finds the willow tree to be an ugly tree. The short-story is that everything this man valued becomes devalued or cast into the world of vision for re-evaluation.
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I read a book about Mike May, who was blinded during an accident as a toddler and who regained sight as an adult. It's a pretty great read: http://www.amazon.com/Crashing-Through-Story-Adventure-Dared/dp/1400063353
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I met a woman a few years back who'd been born blind and gained sight for the first time in her early 40s. She told me that some things were perfectly and immediately recognizable to her, like human faces, and that other things - mostly colors and random objects - were more confusing. She said it took her a couple of years to get "vase" into her head when she looked at one.

She was most confused by colors because to her they seemed so arbitrary. I wish I'd had a week to talk to her. I never found out what her dreams were like before she could see!
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