Daniel Kish has been blind since he was 13 months old, but you wouldn’t be able to tell. He navigates crowded streets on his bike, camps out in the wilderness, swims, dances and does other activities many would think impossible for a blind person. How does he do it? Kish is a human echolocator, a real life Daredevil.
Using a technique similar to what bats and dolphins use, human echo-locators navigate using audio cues given off by reflective surfaces in the environment. Few people know that this same technique can work for human beings. But as a matter of fact, echolocation comes quite naturally to people like Kish, who are deprived of visual information. “I don’t remember learning this,” he says. “My earliest memories were of detecting things and noting what they might have reminded me of and then going to investigate.”
Kish was born with bilateral retinoblastomas, tiny cancers of the retina, which is part of the eye responsible for sensing visual information. Tumors form early in this type of cancer, so aggressive treatment is necessary to ensure they don’t metastasize to the rest of the body.
Unfortunately, the tumors cannot be separated from the retina. Laser treatments are performed to kill them off, followed by chemotherapy. The result is that the retina is destroyed along with the cancer, meaning patients often are left completely blind. Kish lost his first eye at 7 months and the other at 13 months. He has no memory of having eyesight. His earliest vivid memory is from when he was very young, maybe 2½. He climbed out his bedroom window and walked over to a chain-link fence in his backyard. He stood over it, angled his head upward and clicked over it with his tongue, listening for the echo. He could tell there were things on the other side. Curious as to what they were, he climbed over the fence and spent much of his night investigating.
Like Kish, Ben Underwood was a self-taught echolocator and was also diagnosed with bilateral retinoblastomas, in his case at the age of 2. After many failed attempts to save his vision by treating the tumors with radiation and chemotherapy, his mother made the difficult decision to remove her son’s right eye and left retina. This left Ben completely blind.
