May 15, 2020 17:00:00

Succeeded to convey the shape of the letter to the invisible person by embedding the electrode in the brain

As a means of giving eyesight to the blind, research into

implants to be implanted in the eyeball is progressing. As another approach, a study of embedding electrodes in the brain and sending direct signals to make blind people recognize the shape of letters is reported by Bayer Medical University neuroscientist Michael Beauchamp et al. It was.

Dynamic Stimulation of Visual Cortex Produces Form Vision in Sighted and Blind Humans: Cell
https://www.cell.com/cell/fulltext/S0092-8674(20)30496-7

Blind people could 'see' letters that scientists drew on their brains with electricity | Live Science
https://www.livescience.com/drawing-letters-on-the-brain.html

'Because the brain is much more complex than a computer display and there are many things that are not completely understood, it was very difficult to create a recognizable shape with a combination of light stimuli,' Bo said. As neurosurgeon Daniel Josher, the author of the paper, says Champ.

In the experiment, it is said that even if the blind person can recognize letters, by embedding multiple electrodes in the visual cortex of the subject, stimulating the cerebral cortex at several places, and stimulating the reaction of light sense, which is the sense of recognizing light intensity The method was adopted. Just as a computer combines multiple pixels to represent a character or image, it combines electrical dots to send an electrical signal so that the light looks like a character.

The experiment was conducted on a total of 5 people, 3 who were blind and 2 who were blind. Subjects have multiple electrodes implanted in the primary visual cortex of the brain as follows. It should be noted that each subject was selected as someone who had experience of implanting electrodes in the brain in the past regardless of whether they could see or not.

For example, in the case of the letter “N”, by sending stimuli in the order of C06 → F10 → B10 → C10 → E10, the subject succeeded in recognizing the shape of the letter “N”.

The subject wrote on the monitor the visible figure with his / her finger and confirmed whether the actual figure and the figure seen by the subject were the same. The image below shows a state in which the electrode stimulates the brain to draw the letter 'N', and the letter 'N' is clearly written on the monitor.

Peter Roelf Sema, director of the Dutch Institute for Neuroscience, says there are still many challenges to overcome before Beauchamp's work can be applied as a useful visual aid. .. Also, in his paper, Beauchamp et al. Said, 'Our research uses dozens of electrodes, but in the future, thousands will be used for visual aids. It may be designed to penetrate the cerebral cortex and bring the electrode tips closer to neurons hundreds of microns below the surface of the cerebral cortex, 'says the future prospects.