Paralyzed rat is able to walk again thanks to exoskeleton

We’ve seen exosuits that apply external force to allow the paralysed to move their own limbs — but a solution that doesn’t require a chunky, complicated wearable, but relies on internal stimulation, looks like it is on the way. It has been tested and proven as part of a project called NEUWalk by researchers at the École polytechnique fédérale de Lausanne, Switzerland, using a rat with a severed spinal cord — rendering its hind limbs completely paralysed. The project operates on the notion that the human body requires electricity to function. The brain moves the body by sending electrical signals down the spinal cord and into the nervous system. When the spinal cord is severed, the signals can no longer reach that part of the spine, paralysing that part of the body. The higher the cut, the greater the paralysis. But an electrical signal sent directly through the spinal cord below a cut via electrodes can take the place of the brain signal, as the team at EPFL, led by neuroscientist Grégoire Courtine, has discovered. The team severed the spinal cords of several rats in the middle-back, completely paralysing the rats’ lower limbs. They then implanted flexible electrodes into the spinal cord at the point where the spine was severed, allowing them to send electrical signals down to the severed portion of the spine.