Striate cortex advantageous in development of prosthetic device for blind

Using the striate cortex (area V1) for the implantation of electrodes and the study of the feasibility of a prosthetic device for the blind has several advantages, said Peter H. Schiller, PhD, in a symposium about innovations in restoring vision.

Dr. Schiller, the Dorothy W. Poitras Professor in Medical Engineering and Medical Physics in the Department of Brain and Cognitive Sciences at the Massachusetts Institute of Technology, Cambridge, who has conducted this research in monkeys and humans, said the advantages are:

• The area is large, which allows for the placement of many electrodes, and it has well-defined topography.
• The area is lissencephalic in the monkey, which means it is easy to access and provides the researcher with good control over the spatial arrangement of the electrodes placed there.
• The location of the area, under the skull, provides ready access to the system.
• Some depth perception can be realized through motion parallax.
• Using the cortex as a prosthetic area can be accomplished in individuals with destroyed retinas or other ocular damage.

Dr. Schiller described a system that he and colleagues have developed in which images from a camera attached to the head are processed and presented on a monitor; the images mimic the percepts created by electrical stimulation. Using this system, they can determine which information, and how much of it, is necessary for the eye to process two- and three-dimensional stationary and moving images. They are performing this work mainly in humans at this time.