Thursday, December 17, 2009
Tongue Display Unit: It Is Time for the Tongue to Perceive
When we perceive the world around us with our eyes, we seldom realize the gift that we have got. Eyes are so precious that it is difficult to imagine how the blind can manage their life without this beautiful creation. To help the blind overcome their incapacity to see and read, Braille was discovered as a medium of instruction. But today, there is a still more ingenuous device being built which can enable the blind to “see” with their tongue. Although difficult to envisage, a Tongue Display Unit (TDU) can introduce electro tactile signals in the tongue which will help transmit visual images to the brain.
The system involves a webcam and a laptop. The camera intercepts an image in real time which is transmitted to the tongue stimulator array. The communication between the laptop and the tongue device is achieved through wireless Bluetooth which sends the image from the camera to the tongue. The array on the tongue is a grid of electrodes which makes use of electricity to reproduce the image on the tongue. You can imagine the sight which will enable a blind man to see with his tongue. There will be an array of electrodes on the tongue, a microprocessor attached to the neck and a long cord hanging from your lips which will connect to the microprocessor and the camera on your spectacles.
The TDU basically translates visual information into tactile cues. When the electrodes are activated, tiny and simple shapes are drawn on the tongue and the brain can interpret these shapes to indicate to the person what exactly awaits him in the next few steps. The level of detail given in these images is very less. The TDU is expected to be priced at $5000 which might be an impediment for many blind people opting for this device. It is probable that by the time the TDU is finally released in the market, it will have undergone several good changes but nothing can discount the quantity of information which will be transmitted via the sense of touch. The evolution of the brain is also necessary to handle enormous amounts of tactile information at a time.
Source: BrainPort Vision Technology via Scintific and IEEE Spectrum
Tongue Display Unit at Tactile Communication & Neurorehabilitation Lab
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