With new technology that stimulates the brain’s visual centers, blind people can now recognize letters and other simple patterns. This is the first step towards connecting recording devices directly to the visual centers of the brain.
The technology can be compared to our sense of emotions, and it was developed by researchers at Baylor College of Medicine in the United States . If we feel the letter N in the palm, we do not recognize the shape, but if instead it is drawn in the palm, we clearly perceive that it is N.
Similarly, electrodes implanted in the brain’s visual centers can create familiar shapes if activated in a specific sequence.
The reason is that the surface of the visual centers is a kind of map where each point corresponds to a specific point in the visual field.
Like seeing luminous dots
The researchers tested the method on both blind and sighted people who had electrodes implanted in their visual centers as part of epilepsy treatment.
Electrons on the surface of the optical stations draw simple shapes that the blind person can then redraw on a touch screen.
Both groups were able to decode the patterns drawn by the electrodes and then draw them on a touch screen. The people described the sensation as seeing dots that formed the shape.
The resolution of the shapes is still limited by the number of electrodes.
There are about half a billion neurons on the surface of the optic centers, and the experiment only stimulated a small fraction of that number.
The researchers therefore believe that the resolution can be greatly improved with implants containing many thousands of tightly packed tiny electrodes.
