BrainPort Device Lets The Blind Use Their Taste Buds To See

BrainPort, created by neuroscientists at Wicab, Inc., may allow the blind to restore part of their sight by routing sensory information through a different receptor. Using a digital camera and specialized "lollipop", the blind can actually see with their tongues.

The BrainPort device has three components. First, the blind or visually impaired person wears special sunglasses outfitted with a digital camera in its center. The sunglasses are connected to a small handheld device, roughly the size of an iPod. This device features a number of control functions, allowing the user to adjust the zoom and light settings.

Most crucially, this device houses a CPU that converts the images captured by the sunglasses into electrical pulses - the job usually performed by the retina. The final part of the process is to find a replacement for the over two million optic nerves needed in working eyes to transfer visual information from the retina to the visual cortex in the brain. The neuroscientists at Wicab decided to use the huge cluster of nerves found on the tip of the tongue.

To accomplish this, they designed what is essentially an electrode lollipop, which measures about nine square centimeters and can be placed directly on the tongue. Thus, sensors that would usually be utilized to detect different tastes are instead repurposed to process the visual data coming from the BrainPort. The device only allows users to "see" in black and white, as it works by dividing the visual field into a huge field of pixels. White pixels cause a strong electric pulse, while black pixels create no pulse whatsoever.

The neuroscientists know that the device works, but are not entirely certain on some of the specifics. They are not completely sure whether the brain considers the incoming data to be visual - thus sending it to the visual cortex - or to be a feeling of touch on the tongue, which would send the information to the somatosensory cortex. The end result, however, is the same: the user can effectively see, and he or she also feels a crackling sensation on the tongue akin
to drinking champagne or eating Pop Rocks.

This may not necessarily sound like the most practical solution - for instance, it may be difficult for users to see and talk at the same time - BrainPort has one huge advantage over previous devices in that it is not invasive, requiring no implants or surgeries in order to be used. The tongue is the ideal organ for such a device as its nerve fibers are packed close together and are much nearer to the surface than those of, say, the fingers. As an added bonus, the mouth's saliva provides a good conductor for the electrical current.

Users can become acclimated to the device within only fifteen minutes, and from that point can begin to glean spatial information from the pulses received. Four patients are currently testing BrainPort, and they have already been able to locate doorways and elevator buttons, arrange utensils on a dinner table, and even read letters and numbers.

The makers of BrainPort ultimately hope the device will help not only the blind but also those impaired by such diseases as glaucoma. They plan to submit the device for FDA approval by the end of August. Estimating the initial price at roughly $10,000, they hope to have BrainPort on the market by the end of the year.

[Scientific American]