They seek blind volunteers for a pioneering trial that stimulates vision

Scientists from the Miguel Hernández University of Elche, Alicante, are looking for four volunteers to participate in a pioneering trial aimed at stimulating vision in a blind person through a brain implant, so that he perceives simple shapes and letters.

This innovative project, led by Professor of Cell Biology Eduardo Fernández Jover, from the Biomedical Neuroengineering group of the UMH, It comes after a first successful experiment on a 57-year-old Valencian volunteer, Bernadeta Gómez, which has just been published in the Journal of Clinical Investigation.

Fernández Jover explained that the project includes the trial in four more patients with the requirements of good health and that “they are aware that it is an investigation, so they will not regain their vision.”

Is about a new brain implant based on intracortical microelectrodes capable of inducing the perception of shapes and letters in a blind person. According to the results, this micro device is safely implanted and direct stimulation of the cerebral cortex produces visual perceptions with a much higher resolution than had been achieved to date, since the volunteer was able to perceive letters and identify the silhouette of some objects. Even, depending on the intensity of the electrical stimulus, he perceived different colors, sometimes white, yellow or sepia.

In December 2020, a similar experiment was successfully carried out for the first time with primates that were not totally blind, for which an implant with more than a thousand electrodes was used that allowed animals to perceive shapes, movement and letters.

According to the UMH scientist, it is the first time that a brain implant of this type has been performed in a blind person where the results are very encouraging for a future visual neuroprosthesis that helps blind or low vision people to improve their mobility.

Fernández Jover has warned that, although the results are promising, there are still many problems to be solved and it is important not to create false expectations. During six months, the scientists carried out different experiments in the form of games in which the volunteer had to try to recognize letters, the position of stimuli and the shape of different objects, and these tests were repeated several times to see and the possible changes.

The device consists of a small three-dimensional array of 100 micro electrodes only 4 millimeters on a side, with 1.5 mm long electrodes. Another of the conclusions of the study is that this implant does not affect the function of the cerebral cortex or that of the neurons that are located nearby, since “the amount of electrical current necessary to induce visual perceptions with this type of microelectrodes is very high. less than is needed with those located on the surface of the brain, which translates into greater safety. ”

The system includes, in conventional glasses, an artificial retina that emulates the functioning of the human vision system, in such a way that it transforms the visual field into electrical impulses to stimulate neurons.