Researchers for the first time have streamed braille patterns directly into a visually challenged patient’s retina, allowing him to read four-letter words accurately and quickly with the help of a device.
Braille is a tactile writing system used by the visually impaired.
device, the Argus II, has been implanted in over 50 patients, many of who can now see colour, movement and objects with the help of a an ocular neuroprosthetic device. It uses a small camera mounted on a pair of glasses, a portable processor to translate the signal from the camera into electrical stimulation, and a microchip with electrodes implanted directly on the retina.
The study by researchers at Second Sight, the company who developed the device, and has been published in Frontiers in Neuroprosthetics on November 22.
“We bypassed the camera that is the usual input for the implant and directly stimulated the retina. Instead of feeling the braille on the tips of his fingers, the patient could see the patterns we projected and then read individual letters in less than a second with up to 89% accuracy,” said researcher Thomas Lauritzen.
Researchers used a computer to stimulate six of these points on the grid to project the braille letters. A series of tests were conducted with single letters and words ranging in length from two letters to four. The patient was shown a letter for half a second and had 80% accuracy for short words.