Boy uses sound to see

People magazine profiles Ben Underwood, a blind 14-year-old who apparently uses echolocation to "see." Ben, sightless since the age of 3, makes loud clicking noises with his tongue and then listens for the echo. According to the article, he can not only detect distance but sometimes the material of an object based on how soft, dense, or sharp the echo is. From the People profile:

Ben's ability to navigate in his sightless world is, say experts, extraordinary. "His skills are rare," says Dan Kish, a blind psychologist and leading teacher of echomobility among the blind. "Ben pushes the limits of human perception."

Kish has taught echolocation to scores of blind people as a supplement to more traditional methods, such as walking with a cane or a guide dog, but only a handful of people in the world use echolocation alone to get around, according to the American Foundation for the Blind...

Ben learned how to read Braille and walk with a cane, but when he was 3, he also began teaching himself echolocation, something he picked up by tossing objects and making clicking sounds to find them. His sense of hearing, teachers noticed, was exceptional. "One time a CD fell off his desk and I was reaching for it when he said, 'Nah, I got it,'" says Kalli Carvalho, his language arts instructor. "He went right to it. Didn't feel around. He just knew where it was because he heard where it hit." Haase took walks with Ben to help him practice locating objects. "I said, 'Okay, my car is the third car parked down the street. Tell me when we get there,' " she says. "As we pass the first vehicle, he says, 'There's the first car. Actually, a truck.' And it was a pickup. He could tell the difference."

Link to People, More on human echolocation here and here