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Ian Burkhart sustained a severe spinal cord injury while he was on vacation at 19 years old. “It left me as a quadriplegic,” he says. “I had a little bit of movement in my arms, but nothing in my hands.” He wanted something that could give him more independence. And that’s how he came across a clinical trial for a brain implant that would change his life.

Burkhart's device was implanted in his brain around nine years ago, a few years after he was left unable to move his limbs following a diving accident. He volunteered to trial the device, which enabled him to move his hand and fingers. But it had to be removed seven and a half years later.

His particular implant was a small set of 100 electrodes, carefully inserted into a part of the brain that helps control movement. It worked by recording brain activity and sending these recordings to a computer, where they were processed using an algorithm. This was connected to a sleeve of electrodes worn on the arm. The idea was to translate thoughts of movement into electrical signals that would trigger movement.

Burkhart was the first to receive the implant, in 2014; he was 24 years old. Once he had recovered from the surgery, he began a training program to learn how to use it. Three times a week for around a year and a half, he visited a lab where the implant could be connected to a computer via a cable leading out of his head.

“It worked really well,” says Burkhart. “We started off just being able to open and close my hand, but after some time we were able to do individual fin...