In a study published Nov. 9 in the journal Nature, scientists say they have successfully connected brain implants in the motor cortex to epidural stimulation electrode arrays in the lumbar spine of paralyzed monkeys via wireless technology. The brain-spine interface, when activated, enabled the monkeys to resume walking. Lead researcher Gregoire Courtine, who heads up an international team of scientists, claims this specific type of brain-spine interface is a first in spinal cord injury research.

Courtine, a neuroscientist at the Swiss Federal Institute of Technology, told NBC News, “This is the first time that neurotechnology (has restored) locomotion in primates. But there are many challenges ahead and it may take several years before all the components of this intervention can be tested in people.”

Besides the complexity of designing and perfecting a brain-spine interface in humans, another reason for Courtine’s muted optimism is the anatomical difference between monkeys and human subjects. In the study, two monkeys each had one hind limb paralyzed via a clean laboratory transection, leaving them with three working limbs for ambulation. Traumatic spinal cord injuries in humans, typically more complex and varied, usually affect both legs and result in complete or near-complete loss of walking ability. Also, restoring balance in upright humans is a much more sophisticated challenge than dealing with monkeys, whose balance is more easily assured with four limbs on the ground.

The study is noteworthy, however, since it could possibly point the way to further studies that move away from robotic control in an effort to restore volitional control by wirelessly linking the brain to epidural stimulation technology. If successful, it could potentially result in restoring movement in spinal cord-injured humans, however imperfect, without the need to wear cumbersome computer-driven exoskeletons or other external prosthetics.

In a New York Times article, Courtine said that he hoped his team’s new brain-spine interface system could be used “in the next 10 years” on humans in a rehabilitation setting to “improve recovery and quality of life.”

See Courtine explain the procedure in the video below: