Gregoire Courtine is the Director of the Spinal Cord Repair Laboratory at the École Polytechnique Fédérale de Lausanne.
What does the brain-spine interface do?
'The interface links the brain's impulses back to the spinal cord after injury. It's the first time that anyone has been able to do this and get a primate with one paralysed leg to walk again. '
How does it work?
'Electrodes are inserted into the part of the monkey's brain that controls leg movement. The electrical signal is picked up and sent to a nearby computer. We've created a computer program that works out what movement the monkey wants to make. This message is then sent to the stimulator in the spinal cord, which makes the monkey's leg move when it wants to. '
What have been the biggest challenges in your research?
'The idea of linking the brain to the spinal cord is simple, but the major challenge is trying to develop each piece of technology to work in synergy with the body's electrical signals and then put them together. For this we first had to understand the anatomy and physiology of the spinal cord, and then develop the technology. Our team has a lot of different skills: we have neurosurgeons, engineers, primate scientists, physiotherapists and pharmacologists, to name a few. '
What's the next step in your research?
'We've already started testing part of the brain-spine interface in paralysed people. We've implanted the spinal device in two people with spinal cord injuries, to help them move their legs with more control. We've got plans to use it in more people, but we need to test if it works first. '
How will this research affect humans with paralysis?
'At the moment the brain-spine interface isn't an instant cure, but it is a way to enhance recovery for people with incomplete paralysis. Our hope is that one day we can use the whole device to give movement back to people with paralysis. '
What's the difference between the lab and reality?
'The monkeys are easier to treat than humans because their injuries are much simpler. We make a small cut in the spinal cord that gives the monkey temporary paralysis in one leg, but they recover after a few weeks. We couldn't justify anything more serious, as it would be too damaging for the monkeys. '