Brain implant allows paralyzed monkeys to use legs again

Researchers have been working on ways to help the paralyzed regain control over their bodies for a very long time and a team has now made an potentially life changing breakthrough for paralyzed humans. Researchers at the Ecole polytechnique federale de lausanne (EPFL) in Switzerland have been able to give paralyzed monkeys control over their legs again using brain implants. So far testing has been conducted on two rhesus macaques that underwent implantation within two weeks of being injured.

The researchers say that one of the monkeys regained mobility after six days. A pair of wireless implants work together in a brain-spine interface between the brain of the monkeys and the spine of the animals where implants were positioned. Once implanted, the devices communicated via a computer and allowed the brain signals bypass the injured portion of the spine.

The sensors allow the signals from the bain of the monkey to transmit to the spine and stimulate the nerves in the muscles of the monkey's legs where the legs could be activated by the monkey's brain.

"What's key here is that we stimulate to induce the desired movement of the animal," said Grégoire Courtine, professor of neural engineering at EPFL, who led the research. "Over the past decade, we've spent a lot of energy understanding how the spinal cord can be stimulated."

This new research is the first to record brain activity and then link that activity to the nerves within the spinal cord, Courtine says "This is brain control." the interface has two main implants with one of the sensors in the brain and the other being a nerve stimulator on the spine. The sensors are on opposite sides of the injury to the spine to allow communication to resume.

The brain implant is about the size of a dime and is located in the motor cortex region of the brain. The signals are then transmitted wirelessly to a computer that decodes the signals and sends them to the stimulator that is implanted into the spine. The teams says that the injured monkeys were able to walk almost immediately without any training or therapy. The team notes that the research has a long way to go and getting similar results in humans is much more complex than in the monkey tests.