One research team created a wireless brain implant to successfully let two paralysed rhesus macaques walk again.
The wireless system works by bypassing spinal cord injuries and sends signal directly to the lumbar region rather than all the way down the spinal cord.
This is the first time a neural prosthetic restored movement in a primate.
Researchers included collaborators from Switzerland and Germany and added to a sensor technology called BrainGate. The small electrode gets implanted into the brain and gathers movement signals by the brain's motor cortex.
[Image Courtesy of Alain Herzog / EPFL]
The implants were tested on two primates that had paralysis from spinal cord lesions in their upper and middle back. After the receiver activated, the animals moved their legs and could walk on a treadmill almost normally.
The wireless technology served a crucial role, as wired systems can hinder movement.
David Borton from Brown University served as one of the lead researchers for the project.
“Doing this wirelessly enables us to map the neural activity in normal contexts and during natural behavior,” he said. “If we truly aim for neuroprosthetics that can someday be deployed to help human patients during activities of daily life, such untethered recording technologies will be critical.”
[Image Courtesy of Jemere Ruby / EPFL]
This system could eventually restore the ability to walk to humans. However, the team noted several areas of improvement. They said the interface needs a separate computer
The information also only travels one way - from the brain to the legs. In normal function, the legs also send reciprocating information back to the brain for pace, balance and coordination with the rest of the body.
“In a full translational study, we would want to do more quantification about how balanced the animal is during walking and measure the forces they’re able to apply,” Borton said.
However, the team remains extremely hopeful despite its caution.
“There’s an adage in neuroscience that circuits that fire together wire together,” Borton told Brown University news. “The idea here is that by engaging the brain and the spinal cord together, we may be able to enhance the growth of circuits during rehabilitation. That’s one of the major goals of this work and a goal of this field in general.”
Via Brown University, Nature