Once we've tackled those issues, we also have to actually talk in the language of the brain. We have to be able to communicate with the neural tissue. That requires processing a visual picture into a series of impulses like those that the retinal ganglion cells would normally anticipate from the photoreceptor cells. Finally the brain must be able to translate the pulses into an accurate reproduction of the original picture. Despite the considerable work that needs to be done, Drs. Abrams and Iezzi believe that the retinal implant is an achievable goal.
Some steps are already under way.
Dr. McAllister is leading the research on cortical implants. These implants, he explained, would help people who have experienced damage to the entire retina or to other significant parts of the visual system, such as the optic nerve. Dr. Abrams noted that cortical implants would be particularly beneficial for patients with diabetic retinopathy or glaucoma, and those who have many types of trauma-induced vision loss. In these cases, the visual systems have been damaged to such a degree that the best and perhaps only hope of restoring vision is through the visual cortex. Electrode arrays in the preliminary implant.