It sounds like a science fiction movie: a blind man wearing sunglasses licks a plastic lollipop and can suddenly see. This device, however, exists today. The Brain Port—a contraption comprised of a tiny video camera attached to a pair of sunglasses linked to a plastic “lollipop”—is enabling the blind to see . . . with their tongues.
The idea started with Paul Bach-y Rita, a neuroscientist at University of Wisconsin-Madison. Bach-y-Rita was convinced that the brain, not the eye, is what enables humans to see. Furthermore, Bach-y-Rita argued that the adult brain is plastic and can rewire nerve impulses from anywhere—not just the eye—to generate vision.
Bach-y-Rita and his colleagues began their work by stimulating skin on the back and abdomen in lieu of the eye.1 Their results were positive: with training, blind people learned to interpret patterns of excited nerve endings on their skin as visual images. Determined to make a more practical, user-friendly device, Bach-y-Rita moved the tactile stimulation to a body part with finer discriminatory abilities: the tongue, which, apart from the lips, contains more nerve endings than any other part of the body.2
Thus, the Brain Port was born. The device is comprised of an inch-long video camera mounted on a pair of sunglasses. The camera sends signals down a cable to a handheld control unit about the size of a cell phone, which converts the image into a low resolution black, white and grey picture. That picture is then recreated as a square grid of 400 electrodes, approximately the size of a postage stamp, on the lollipop-shaped stick. Each electrode sends pulses based upon the amount of light detected, with strongest pulses for white, and no signal for black.
By this method, the tongue becomes the “surrogate eye.”
Although Bach-y-Rita passed away in 2006, the Brain Port continues to be developed by Wicab, a company he cofounded in Middleton, Wisconsin in 1998. While it was initially meant as a tool for the blind, other groups are developing the Brain Port for different purposes:
- The U.S. Navyis developing a system that will allow divers to find their way through murky waters by interpreting infrared through their tongues.
- NASAis creating sensors to enable astronauts to feel objects on the outside of their space suits.
- The Institute for Human and Machine Cognition is working toward making vests that will alert pilots to other planes or incoming missiles by tickling them.
Learn more about human-machine interaction in Intelligent Wearable Interfaces.
1 BACH-Y-RITA, P., COLLINS, C., SAUNDERS, F., WHITE, B., & SCADDEN, L. (1969). Vision Substitution by Tactile Image Projection Nature, 221 (5184), 963-964 DOI: 10.1038/221963a0
2 Sampaio, E. (2001). Brain plasticity: ‘visual’ acuity of blind persons via the tongue Brain Research, 908 (2), 204-207 DOI: 10.1016/S0006-8993(01)02667-1