Health & Wellbeing

BrainPort for the visually impaired - ‘seeing’ with the tongue

BrainPort for the visually impaired - ‘seeing’ with the tongue
The BrainPort device helps the blind to 'see' through their tongues
The BrainPort device helps the blind to 'see' through their tongues
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The BrainPort device helps the blind to 'see' through their tongues
The BrainPort device helps the blind to 'see' through their tongues

According to the National Institutes of Health, more than one million Americans over the age of 40 are legally blind - defined by U.S. law as vision that is 20/200 or worse, or have a field of view that is less than 20 degrees in diameter. It is estimated that adult vision loss costs the country about $51.4 billion per year. A new device aims to help restore the experience of vision for the blind and visually impaired by using nerves on the tongue's surface to send light signals to the brain.

Humans use around two million optic nerves to transmit visual signals from the retina — the portion of the eye where light information is decoded or translated into nerve pulses — to the brain's primary visual cortex.

BrainPort is a device being developed by neuroscientists at Middleton, Wisconsin–based Wicab, Inc. (a company co-founded by the late neuroscientist Paul Bach-y-Rita) that helps users ‘see’ without using their eyes. Bach-y-Rita hypothesized in the 1960s that "we see with our brains not our eyes."

Using the BrainPort device, visual data is collected through a small digital video camera, about 1.5cm (5/8 inch) in diameter, housed in the center of a pair of sunglasses worn by the user. From there, the data is transmitted to a handheld base unit about the size of a cell phone. The unit converts the digital signal into electrical pulses — replacing the retina’s function.

The base unit also incorporates features like zoom, light settings and shock intensity levels as well as a central processing unit (CPU).

Tasting is believing

Signals are sent from the CPU to the tongue via a ‘lollipop’, an electrode array about 9 sq cm (1.4 sq inch) that sits on top of the tongue. Each electrode corresponds to a set of pixels: white pixels, for example, deliver a strong electrical pulse whereas black pixels have no signal. Densely-packed nerves on the tongue surface receive the incoming electrical signals, which users describe as feeling a little like Pop Rocks or champagne bubbles.

At this stage, Wicab neuroscientist Aimee Arnoldussen says it remains unclear whether the information is then transferred to the brain's visual cortex, where sight information is normally sent, or to its somatosensory cortex, where touch data from the tongue is interpreted. Either way, the results are promising.

Learning curve

Presently, it only takes around 15 minutes for users to start interpreting spatial information via the BrainPort, says William Seiple, research director at the non-profit vision health care and research organization Lighthouse International.

For instance, Seiple says if the camera detects light fixtures in the middle of a dark hallway, corresponding electrical stimulations will occur along the center of the tongue.

"It becomes a task of learning, no different than learning to ride a bike," Arnoldussen says, adding that the "process is similar to how a baby learns to see. Things may be strange at first, but over time they become familiar."

Seiple has four patients who train with the BrainPort once a week, all of whom have made quick progress in undertaking what sighted people take for granted, like navigating through doorways, finding elevator buttons, reading letters and numbers, and distinguishing cups and forks at the dinner table without fumbling around.

"At first, I was amazed at what the device could do," he said. "One guy started to cry when he saw his first letter."

The price of ‘sight’

Wicab says it will submit BrainPort to the U.S. Food and Drug Administration for approval at the end of the month and hopes the device will be approved for market by the end of 2009. Robert Beckman, president and chief executive officer of the company, anticipates a cost of about $10,000 per machine.

Wicab is working with the University of Pittsburgh Medical Center's UPMC Eye Center for further testing on BrainPort, along with other artificial devices such as retinal and cortical implant chips, in order to develop criteria for monitoring the progress of artificial sight.

"We can't just throw up an eye chart,” says optometrist Amy Nau. “We have to take a step back and describe the rudimentary precepts that these people are getting. The images are in black and white, pixilated. How do you recheck vision?"

Nau likes the BrainPort because it is non-invasive, unlike implants.

The key to the success of the device lies in its utilization of the tongue, which seems to be an ideal organ for sensing electrical current, as opposed to the surfaces of fingers, for example, which are covered with a layer of dead cells called stratum corneum.

"Many people who have acquired blindness are desperate to get their vision back," Nau says, and although sensory substitution techniques can’t fully restore sight, they do help with spatial orientation and deliver more independence to the blind and visually impaired, including those suffering glaucoma.

Via Scientific American

Brainport Vision Device

Yuri Danilov
I am writing on behalf of the scientists and engineers, who invented, designed and developed this original technology under supervision of our friend and mentor Paul Bach-y-Rita at the University of Wisconsin, Madison (1992 -2005) - Kurt Kaczmarek, Mitchell Tyler and Yuri Danilov. The name Brainport reflects the major goal of this technology - to transfer into the human brain the flow of information from outside environment using as an alternative channel, human skin and the surface of the tongue for particular applications to help people who lost natural sensory systems (vision, hearing, vestibular). Even more, this technology applied as a unique machine-brain interface can extend human abilities in limitless applications for navigation (including firefighters and scuba divers), communication, entertainment and other areas of everyday life and human activities, see Danilov, Yuri, Tyler, Mitchell. BrainPort: an alternative input to the brain. Journal of Integrated Neuroscience, 2005, 4, 4, pp.1-14.
This technology was patented in University of Wisconsin, Madison by Kurt Kazcmareck and Paul Bach-y-Rita. The Wicab, Inc. was founded by Mitchel Tyler and Paul Bach-y-Rita to speed up commercialization of BrainPort® technologies. Unfortunately, authors did not explore scientific basics of this technology and missed a further perspective even for the current device for the blind. There is at least theoretical perspective for future development of color and stereoscopic vision for the blind; it is also very intriguing to explore combination of this technology with existing methods and tools developed for artificial visual systems. Interestingly, the blind subjects are intensively using the camera zoom on the current BrainPort vision device, even if it was not included in our original natural design. As a scientific research tool, this technology can facilitate our understanding of brain plasticity, open new areas of research in human psychophysics (basically we discovered new way to utilize the electrotactile sensory system), help to understand interactions of information flows in the human brain. As a clinical tool for sensory substitution, this technology tremendously changed the quality of life of people with sensory loss, for example, see PBS video clip, Since 2006, when Paul Bach-y-Rita died, all original inventors and developers of BrainPort technology are working in the University of Wisconsin, Madison, Tactile Communication and Neurorehabilitation Laboratory, Orthopedic and Rehabilitation Medicine Department, web site:
Nakrekanti Narayanarao
Brain Port for the visually impaired - ‘seeing’ with the tongue
I live in India.. my wife lost eye sight due to retina degeneration, she cannot see , and only can feel the light and not objects.. when the brain port device available in India, and cost price in indian rupees, to enable me to order for it...narayanarao