Gert-Jan Oskam was paralyzed in an accident eleven years ago; Today, at the age of 40, he is able to stand on his feet, walk and control his movements again, thanks to a new technique described in the journal Nature that offers new perspectives to people with spinal cord injuries. It’s a device that creates a “digital bridge” between his brain and the nerves under the wound: the brain “communicates” directly with the part of the spinal cord that controls movement, allowing it to travel short distances to stand and walk naturally with the help of a crutch. The technique was developed by the Lausanne Polytechnic research group led by Grégoire Courtine, who last year experimented with an electrode system that can be controlled with a tablet and sends electrical stimuli to the muscles in a programmed way. And Oskam experienced that himself. Researchers are working to continue the experiment, which involves three other paralyzed people.
Check the movement
The new device builds on previous work by the same study group. Compared to the previous device, which connected to the tablet and generated robotic movements, “the new system is completely different,” explained Courtine. “Oskam has full control over the stimulation parameters, which means he can stop, he can walk, he can climb stairs.”
The system at the base of the digital bridge consists of 64 electrodes that record motor cortex signals using frequencies identified by artificial intelligence. When people think they are walking, the implants detect electrical activity in the cortex; The electrical signals are transmitted to the spinal cord, where they are received by 16 electrodes and decoded in real time. This signal is wirelessly transmitted and decoded via a portable control system contained in a backpack.
The comment
Comments Silvestro Micera, Full Professor of Electronic and Computational Bioengineering at the Sant’Anna School in Pisa: “The study confirms the results obtained over the years by this research group, led by Professor Courtine, to study paralyzed people with spinal cord injuries to be able to walk again.” The novelty is that the possibility of voluntary control of movement is added. In practice we try to restore movement through thought. Previously, patients used a tablet-based system, so there was involuntary movement control. According to animal studies that have already been carried out, it is now possible to restore voluntary movement control, ie as before the accident, which paralyzed the patient who thought he was going to walk and so he did it. This new technique allows voluntary movement to be restored and, in addition, can improve walking performance.”