Cutting Edge: 'Seeing' Through Tongues Tongue Sensors May Give Virtual Eyesight to the Blind By Michael S. James ABCNEWS.com March 30, 2001 Blind people have always had to feel their way through the world. Someday soon, they may be able to taste their way as well. Researchers at the University of Wisconsin at Madison are developing a device that will allow people to "see" the world with their tongues. They say the tongue is an effective portal to the brain because of its sensitivity, and electrical impulses created by a camera and a computer can allow users to sense objects in space, as impulses from working eyes do naturally. "Initially, when you first start training on it, you feel everything on the skin [or the tongue]," says Dr. Paul Bach-y-Rita, a professor of rehabilitation medicine and biomedical engineering at the University of Wisconsin. "But after about 10 hours, you forget about the skin and feel everything in space." After being trained with the device, subjects are able to sense their surroundings and react to them automatically, Bach-y-Rita says. New users tell him the array of electric stimulators on the tongue feels "like bubbly water, or champagne bubbles," though the sensation fades into the subconscious as users become accustomed to it. 'Cool Approach' It's a tasty concept to Dr. Michael D. Oberdorfer, director for the Low Vision and Blindness Rehabilitation Program at the National Institute of Health's National Eye Institute, who has cleared a preliminary $100,000 grant to one of Bach-y-Rita's Wisconsin colleagues. Although the idea of people sensing through their tongues may seem strange at first, Oberdorfer says it is not so odd upon considering the tongue's sensitivity, and that its moisture creates an effective conductor of the electrical impulses. "It seems obvious once you see it, but who would've thought?" Oberdorfer says. "This is a very interesting, cool approach, and they're taking it in several different directions." In addition to systems for the blind, Bach-y-Rita says the technology could have other applications, because designers can create impulses from any measurable source. He is in discussions with the military regarding devices to allow divers to "see" more effectively through murky water using their mouthpieces, or to allow soldiers to receive night vision readouts through their tongues. He adds that the tongue sensors could one day be used in conjunction with video games, and his team has received a federal grant for a system that will aid people who've lost their sense of balance. Refinements Needed Researchers still are refining their products for the marketplace, and predict it will be several years before they are perfected and available. For one thing, they still are trying to perfect an unobtrusive retainer to be worn inside the mouth over the palate. For the time being, they still are placing electronic ribbons in their subjects' mouths - a method that is uncomfortable and only allows for half-hour testing sessions. "Technology exists now to put the whole array, the electronics, the battery, everything into a dental retainer," Bach-y-Rita says. "It's just that to make the whole package is expensive, and that's what we're working on." He believes that once the miniaturization is perfected, producing the devices will become less expensive. For the vision-substitute devices, subjects still are carrying a camera and are tethered to a computer that turns the images into electrical impulses, Bach-y-Rita says. But he envisions a system not too far in the future where a camera and computer are mounted in specialized glasses, and FM signals are transmitted wirelessly to the retainer's stimulators. He predicts that if funding sources come through, schools could be training blind children in visual spatial concepts with the devices in two years, and the general blind population could be using them in five years. However, it may be a few more years before blind people will be able to heavily rely on the devices as a substitute for everyday vision. "When you walk down a street, you're getting all sorts of visual clutter," Bach-y-Rita says. "It's a huge amount of information that you have to deal with. We're not comfortable in doing that yet, although we think it's doable."