'Lollipop' Device Helps Reveal Shapes To the Blind
Tuesday, July 21, 2009
After Marine Cpl. Mike Jernigan was blinded by a roadside bomb in Iraq, he said, not much was done for him.
"I returned back from Iraq and [Veterans Affairs] gave me a stick. A stick and a tap on the butt and they said, 'Go ahead.' "
Five years later and thanks to the ambitions of a handful of people, Jernigan has more than a walking cane. He has been given a special "lollipop," a device that uses his tongue to stimulate his visual cortex and send sensory information to his brain.
Also called the intra-oral device, or IOD, the lollipop is an inch-square grid with 625 small round metal pieces. It is connected by a wire to a small camera mounted on a pair of sunglasses and to a hand-held controller about the size of a BlackBerry. The camera sends an image to the lollipop, which transmits a low-voltage pulse to Jernigan's tongue. With training, Jernigan has learned to translate that pulse into pictures. He can now identify the shapes of what is in front of him, even though both of his eyes have been removed.
"It's kind of like Braille that you use with your fingers," said Amy Nau, an optometrist who is researching the effectiveness of the device at the University of Pittsburgh. "Instead of symbols, it's a picture, and instead of your fingertips, it's your tongue."
The machine is called the BrainPort vision device and is manufactured by Wicab, a biomedical engineering company based in Middleton, Wis. It relies on sensory substitution, the process in which if one sense is damaged, the part of the brain that would normally control that sense can learn to perform another function. In Jernigan's case, the visual cortex is recruited to take on tactile recognition.
"Touch takes over for vision in this case," said Maurice Ptito, a professor of visual science at the University of Montreal's School of Optometry, who has scanned the brains of blind people using the machine. "We notice that they activate the visual cortex, which is the part of the brain that a seeing person would use."
Bob Beckman, the president and chief executive of Wicab, said the BrainPort might be on the market by the end of the year, priced at about $10,000.
Jernigan, 30, who lives with his wife and stepson in McLean, received his BrainPort from Wicab for free as one of more than 100 blind people who have tested the instrument. He communicates with researchers about its benefits and limitations.
"It is designed for stationary tasks," he said. If the camera were to transmit images of a moving scene, there would be "too much information to process at once."
Still, Jernigan uses the BrainPort for everything he can. "When your sink gets clogged up, you got pieces laying down on the floor," he said. "It helps you find your pieces."
Jernigan recently demonstrated the device at the University of Pittsburgh Medical Center. He sat with the lollipop in his mouth wearing camera-equipped Oakley sunglasses as Gale Pollock, the center's executive director, stuck simple white felt shapes on a black felt screen. After she placed each shape in front of him, she asked, "Mike, what do you see?" After a few seconds, Jernigan answered correctly each time. "Horizontal line," he said. "Circle." "Diagonal line pointing that way," showing the line's direction with his arm.
"This device does not give you your sight," Jernigan said. "There is not that picture in your head."
"When you were a child, did anyone ever draw a picture on your back?" Beckman asked during a phone interview. He said receiving information via the BrainPort is similar to perceiving a shape sketched on your skin by a person's finger.
"It's a first step," said Pollock, a retired Army general. "It's very elementary, but for so many generations the visually impaired and blind have been told, 'I'm sorry, there is nothing that we can do.' "
Nau said the "vision" produced is very rudimentary. "Blocks, shapes -- it's black and white," she said. "There is no stereo vision," or depth perception.
Beckman said the company's mission is not to re-create vision but to provide information. "I think we are in the infancy of this technology," he said.
Paul Bach-y-Rita, the late founder of Wicab, discovered in the late 1990s that the tongue was the ideal place to provide information through tactile stimulation, Beckman said. "There is a high level of nerve endings in the tongue, similar to a finger," he said. "And the tongue is constantly moist, so there is constant electric conductivity."
Beckman said a finger would require 10 times more electric stimulation than the tongue does to produce the same results in the visual cortex.
There are no known risks associated with the BrainPort, according to Nau, though some patients have reported a tingling sensation on their tongues after using the device.
Jernigan said the electric stimulation on his tongue is mild. "You ever stick a nine-volt battery on your tongue?" Jernigan asked during a phone interview. "It feels like that, but less. It's not as intense as that."
Jernigan said he uses the controller to tweak the strength of the stimulation. "You can make it more powerful if you'd like," he said.
Jernigan, who is studying government affairs at Georgetown University but will be moving to St. Petersburg next month to attend the University of South Florida, said the BrainPort allows him a better life.
"For five years I have stared at a blank, black screen," he said. "People are thinking outside of the box, and by doing so, it allows someone like me to have the hope of the possibility that I might see again."