I can only imagine how hard it must be to get around without the sense of sight. I have never imagined, however, that my tongue could help guide the way.
But, according to an article in New Scientist magazine, engineers at the University of Wisconsin at Madison have dreamed up a contraption that would enable me to do just that. Does that mean you have to taste everything you encounter? Happily, no. Instead, images from a video camera are converted into electrical signals that send instructions to a grid of 144 electrodes held neatly on the surface of your tongue. Instructions that tell you to turn left. Turn right. Or proceed straight ahead. We called the intrepid researchers to learn more.
It's early days for the device in question, says Kurt Kaczmarek, a member of the tongue-device research team. No one's yet been let loose with it at a busy intersection. Plus, for now, you'd have a flat sort of wire coming out of your mouth and you'd have to lug around computer gear, too. (The researchers are working on miniaturizing the device.) But people who've tried navigating a maze on a computer find they can tell which way to turn quite nicely from the tingles on their tongues.
All very clever, but why--of all body parts--choose the tongue? It makes good sense, says Kaczmarek. The tongue--like the fingertip--is densely coated with sensory nerves so you can get a good spatial "picture" when it's electrically tingled in different places. The fingertip, however, responds differently to the sensation when it's sweaty or dry--which means it's harder to make sure that the electrical signal is strong enough to feel, but not so strong that it makes you go "Yipe!"
"The tongue," says Kaczmarek, "is largely immune to that problem because it is always wet."
Rosie Mestel, Los Angeles Times.