Friday, July 11, 2008

Blind Climber "Sees" With His Tongue

I just read an article that is personally fascinating to me for a couple of reasons.

First, the article,
The Blind Climber Who “Sees” With His Tongue,
Which Appears online in

Discover Magazine,

Is about Erik Weihenmayer, a personal hero of mine. For those who do not recognize the name, Weihenmayer is the blind mountain climber who reached the summit of Mount Everest in 2001.

Secondly, the article, discusses the latest advancements made with the BrainPort,an assistive technology device that allows blind people to see using their tongues, rather than their eyes. In the early years of adjusting to the adventitious blindness in my life, I was seeking a miracle that would reverse the severed optic nerves and, for a time, put my life on hold waiting for this to occur. Accepting the reality of my situation, I let myself move forward with life, but I still long to hear of news such as the Brainport device. When I came to the point of accepting the blindness, I realized that the technological and medical advances that were to come during my lifetime were most likely going to allow me to see in some form again at some point. One thing I never dreamed about, though, was that this might mean using my tongue to see.

From the article:



In normal vision, light hitting the retina provokes electrical impulses that the brain translates into images. What the tool, called the BrainPort, does is convert light into electrical impulses that stimulate the tongue instead of the retina. With more tactile nerve endings than any other part of the body except the lips, the tongue can discriminate two points spaced less than a millimeter apart. That degree of resolution is far beyond what the current BrainPort array, with only 611 electrodes, provides. But tests have shown the BrainPort delivers enough information for users like Erik to navigate with.

“Climbing!” Erik calls out to his partner. He places the device in his mouth, raises his head, and “surveys” the wall before him. Electrical impulses from the BrainPort become to him “a tactile image that I’m interpreting in space.” Erik reaches for a handheld slider that controls the zoom level and field of view of the BrainPort so that he can “see” one or two rock climbing holds on the wall some 2 or 3 feet above him. Then he slowly and deliberately raises his right hand, reaches up, grabs hold, and begins to pull himself up the wall. His feet secure, he hangs for a moment, adjusts the zoom again, then tentatively puts his hand out and above him again, this time missing the hold by half a foot. Judging the distance of an object in space is particularly difficult even with the device, Erik says. To help him figure out how far away something is, he sometimes waves his hand—an object of known size and distance—in front of himself first to get a sense of scale via the BrainPort array. The feedback helps him assess the distance of his next rock climbing hold.

Testing the BrainPort, Erik says, involves “learning to climb in a new, different way. I’m learning another language in the same way someone would be learning Braille or French for the first time. I’m figuring out how to map it spatially.” The challenges are significant. The BrainPort provides information in two dimensions, like a line drawing on a piece of paper, but the user’s brain must learn to translate this information into things like perspective, dimension, and location in space. When Erik first used the BrainPort, the images in his brain appeared as unidentifiable shapes and lines, but over time, through practice, his brain adapted, eventually translating the tactile sensations into recognizable patterns and symbols.



Thanks to the assistive technology news site,
Axistive.com,
For this encouraging and interesting news update.

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