If your spine is injured, communication between the brain and the lower limbs is impaired or severed, resulting in paralysis. Now scientists have bypassed this damage in monkeys, using Wi-Fi to send nerve signals to the legs.
This new link is simple in concept. A chip implanted in the monkey’s brain reads signals that are meant for the legs, and sends them wirelessly to a computer. Then the computer interprets these instructions, delivering electrical stimulation to the actual nerves, skipping the broken connection in the spine. The result is that the subject can actually walk, regaining control of the paralyzed leg.
“The movement was close to normal for the basic walking pattern,” one of the paper’s authors, Dr. Gregoire Courtine, told the BBC, “but so far we have not been able to test the ability to steer.” The test monkey has so far only been able to walk in a straight line on a treadmill.
The next step is figuring out how to make this work in humans. The implantable components have all been approved for use in human testing, but the barrier might be the complex human gait. “The way we walk is different to primates,” says Courtine. “We are bipedal, and this requires more sophisticated ways to stimulate the muscle.”
The big advantage of this method is that it is minimally invasive in terms of implants. You need a tiny chip in the brain, and a way to get electrical signals into the nerves at the other end, but that’s it. The computer part can be kept outside the body, and because it’s wireless, there’s no need to run cables from the brain in order to replace the spine’s physical connections.
But the wireless nature of the signal could also be a liability outside the controlled lab environment. The signals might fail, just like your home Wi-Fi connection sometimes goes on the fritz. Worse, wireless medical devices can be hacked. It’s already happened to Johnson and Johnson’s insulin pump, and a group of scientists and neurosurgeons consider the threat so real that they authored a paper warning of the dangers, and outlining the steps that can be taken to protect us as we get more and more implants.
Wireless implants seem to figure big in our medical futures. Curing paralysis without major surgery is a big deal, so lets hope that the industry does a better job of securing their products than the manufacturers of those internet-breaking toasters.