Microelectrodes implanted in the brain of a patient with amyotrophic lateral sclerosis (ALS) were able to capture neuron activity allowing him to communicate again. The signals of brain activity captured by implants in the motor cortex, the area of the brain responsible for movements, were decoded by an algorithm developed through machine learning.
ALS is a neurodegenerative disease that destroys the nerves that control the movements of the body causing the person to lose command of the muscles and thus the ability to move, speak, and in the most advanced stage even breathe. The disease, which became better known a few decades ago for having affected the physicist Stephen Hawking , gradually condemns the patient to extreme isolation.
Science and technology have already made it possible to advance and improve the survival of those suffering from the disease. When the patient loses the ability to speak, communication can be done by selecting letters on a screen using an eye-tracking camera. At a later stage, it is possible to answer yes or no with subtle eye movements.
The study conducted by researchers from the Wyss Center for Bio and Neuroengineering in Switzerland and the University of Tübingen in Germany paves the way for new technologies on the communication of people with severe paralysis.
Without the movements of the body and already unable to speak, but with mental abilities and hearing still preserved, the patient participating in the study received two implants with ninety-six microelectrodes each. Then, for months, they calibrated the technique according to the responses they obtained and adjusted the system to capture neurons with more activity. At the same time, the way each of them behaved in response to the patient’s efforts was monitored.
Neural signal capture brings up a relevant ethical question
The first intelligible sentence was a request for his caregivers to change the position of his body. Communication, however, is sporadic and scientists cannot know for sure whether when there is no communication it is by the patient’s will or because the brain signals are too weak to be picked up and decoded.
Although the study brings encouraging perspectives that it is possible to maintain communication with a person as they lose some other of their skills, the results also indicate that a large financial investment and time is needed to develop a system capable of being used by several patients, since it depends on specific adjustments to the condition of each one.
The reading of neural signs also brings a relevant ethical question. The patient in this study authorized the implantation of microelectrodes in his brain so that he could maintain communication for about three years, during which he could still move his eyes. However, with the progressive loss of the movements, he would not be able to express his will if he decided to give it up. And there’s no way of knowing whether he still wants his brain signals to be accessed or even if they’re actually translating his desires.