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A quadriplegic man in the US has been able to use his right arm and hand again after eight years of paralysis.

Bill Kochevar, who was paralysed below his shoulders in a cycling accident, was able to do this thanks to a neuroprosthesis. Electrodes implanted under his skull record brain activity in his motor cortex region, sending signals to electrodes in his arm that tell them when to stimulate his muscles.

The device has enabled him to raise a mug of water and drink from a straw, and scoop mashed potato from a bowl. “For somebody who’s been injured eight years and couldn’t move, being able to move just that little bit is awesome to me,” says Kochevar.

In preparation, Mr Kochevar first learned how to use his brain signals to move a virtual-reality arm on a computer screen. “He was able to do it within a few minutes,” says , from Case Western Reserve University, in Cleveland, Ohio. “The code was still in his brain.”

After four months of practice, he could take control of his own arm and hand, with the help of a mobile support that stops gravity from getting in the way.

Kochevar isn’t the first paralysed person to regain control of an arm and hand. Last year, Ian Burkhart was able to pick up and pour a bottle, and even play the Guitar Hero computer game, thanks to a brain implant connected to an external sleeve of electrodes placed over his arm. In 2015, a brain implant enabled Erik Sorto to drink a beer at his own pace using a robotic arm.

But restoring movement to paralysed people isn’t the only goal. One team has made a mind-controlled robotic arm that actually feels like a person’s own hand, sending sensations back to a quadriplegic person’s brain. Brain implants have also let a locked-in woman with amyotrophic lateral sclerosis (ALS) communicate by thought alone.