PITTSBURGH -
Mark Pappas lost his sight completely 14 years ago from meningitis. Now, at 37, he's learning to "see" with his tongue. Pappas is part of an experimental trial at the University of Pittsburgh Medical Center. He's wearing a small video camera that's connected to a sensor in his mouth. Tiny electrodes stimulate the nerves on his tongue.
"That's where you feel a pin pricking sensation. Almost like static on your tongue," Pappas said.
They translate what the camera sees into basic shapes and contrast, giving him a sense of what's in front of him. He doesn't actually see anything, but remarkably, his brain is learning to distinguish between letters and objects.
"What it's doing is essentially what Braille does," said Dr. Amy Nau of the UPMC Eye Center. "This is the same exact thing; it's just that it's a video stream. And instead of using the fingertips, you're using the tongue."
For someone who can see, the device may not seem like much help at all. But when you have no vision, any information about your surroundings is a huge step forward.
"I liken it to you being in a completely dark house. And if you just get a little bit of light coming in from a window, you can orient yourself," Nau said.
The next stage of the trial is for Pappas to try to master the device at home.
"Any little bit of independence I can get from this is worth its weight in gold," he said.
He looks forward to the day when he can walk, comfortable with the device on his own.
Researchers say they chose the tongue because it's so sensitive and can handle much more information as the device evolves.