US scientists are developing a light-sensitive microchip that will hopefully help blind people to regain at least some of their sight. The chip, which is designed to be positioned on the retina, contains 1,000 minuscule electrodes, which will hopefully stimulate the neural pathways that convey images to the brain. Normally, the light-sensitive rod and cone cells situated on the retina convert light into electrical impulses. However, in diseases such as age-related macular degeneration and retinitis pigmentosa these cells are damaged, although the pathways that transmit the impulses to the brain remain intact. The patient will wear a pair of glasses that contain a camera and a radio-frequency transmitter that will power the chips and relay information to them. The chips themselves will be linked to retinal nerves. While the chip is not designed to fully restore sight, it is hoped that it will enable the patient to read and distinguish objects. According to project leader Kurt Wessendorf, of the Sandia National Laboratories, “The images will come a little slowly and appear yellow. But people who are blind will see.”
SOURCE/REFERENCE: Reported by www.bbc.co.uk on the 3rd October 2002
