A team of Swiss and French scientists has achieved an enormous advance in neural surgery, reported today in the prestigious scientific journal “Nature”: a paraplegic man has been able to walk again through the first human-machine connection or interface trained with artificial intelligence.
This advance was presented at the Vaud University Hospital Center (CHUV), in the Swiss city of Lausanne, where the first patient on whom it has been tested, a 40-year-old Dutchman named Gert-Jan who lost the mobility of his legs in a bicycle accident 12 years ago, walked in front of the journalists.
“Four years ago I did not even dream of something like this,” the patient told EFE, who was invited in 2016 by Swiss scientific institutions to participate in the program, previously experimented with apes but until then had not been tested on humans.
Gert-Jan underwent operations in which two implants were placed: one in the spinal cord, and another more complex, an interface or connector between the human brain and a computer that, through 64 electrodes, collects brain stimuli and translates them into digital data after a learning phase of both the human and the machine, thanks to artificial intelligence in this second case.
“This interface is capable of recording brain activity on the surface of the cortex,” researcher Guillaume Charvet, from the Atomic Energy Commission, a French institution that has worked on the project together with the aforementioned CHUV, the Federal Polytechnic School of Lausanne, explained to EFE. (EPFL) and other organizations.
After receiving these implants, the patient was asked, in a phase that required months of training, to imagine moving his legs: In doing so, his brain emitted stimuli that, through algorithms, were converted into data that would later reach the implant in his spinal cord and be converted into movement.
“It was the hardest part, thinking about natural movement after 10 years without trying,” Gert-Jan acknowledged.
At first he trained his movements on an avatar, a digital and screen version of himself that began to move with his thoughts, and eventually the system took his own spinal cord.
“In a few minutes I could already move the avatarso we decided to try to see if he could get up, and when he took his first steps we almost cried to see that he had been so fast,” neurosurgeon Jocelyne Bloch, another of the main people in charge of the project, recalled in statements to EFE.
The patient now walks with the help of a walker, and the brain-machine system, which has not yet been miniaturized, is still somewhat cumbersome, since the patient needs headphones to send his orders through waves, and a laptop resting on the walker to decode them before they are delivered to the spinal cord, in a matter of two to three tenths of a second.
In any case, the advance in neuroscience is enormous, according to the researchers themselves, for the important link that has been achieved between brain and machinealso using a technology as promising as that of artificial intelligence.
“The next step is, of course, to spread this technology to more patients, and for that we need to industrialize it,” said Bloch, a professor at both CHUV and EPFL and at the University of Lausanne (UNIL), another center linked to the project.
In this sense, the Dutch company Onward Medical has already obtained support from the European Commission to develop, together with research institutions, a commercial version of this digital interface.
The researchers also highlight among the goals to be achieved in the near future that of bringing this mobility to the upper extremities (arms and hands) in order to be useful also to tetraplegic people.
For Gert-Jan, who says she has rediscovered simple pleasures such as drinking a beer standing in a bar with her friends, the next goal is to be able to walk without the help of a walker: “I think I could take a year off training,” he says.
Other people in charge of the project are the professor of neuroscience Grégoire Courtine and the person in charge of the brain-computer program at EPFL, CHUV and UNIL Henri Lorach.
The brain implant, about two inches in diameter and which includes antennas to send the patient’s orders without the need for cables, requires a craniotomy, in which a part of the skull is replaced by this device.
According to its creators, this technology could also be applied to people who have been paralyzed by a cerebrovascular attack or stroke.
Professor Bloch stressed that a condition for it to be applied is that the patient has at least six centimeters of their spinal cord intact, since it is in them that the electrodes are inserted to control the movement of the extremities.
“We estimate that it will take about five years before it can be extended to everyone, but in the meantime, we are going to acquire a lot of knowledge in the project,” he anticipated.
The project could go even further and serve to recover lost natural neurological functions: improvements in sensory perceptions and motor skills have been identified in the first patient, even with the interface turned off, a kind of “digital repair” of the spinal cord in which nerve connections have developed.