A former soldier has been fitted with what's thought to be Britain's first mind-controlled bionic limb.
Corporal Andrew Garthwaite has been given the high-tech hand after he was injured in Afghanistan three years ago.
The device is one of the most advanced prosthetic arms available - Andy can use his brain to control it.
Unlike most prosthetic limbs this one can be controlled by thought alone: Andy just has to think about moving his arm and the robotic arm will move.
How does it work?
It's been a long process to get to this stage.
To prepare for the technology he had six hours of surgery at a hospital in Austria in January 2012 in a procedure called Targeted Muscle Reinnervation (TMR).
Surgeons had to rewire his nervous system: they took the nerve endings from his shoulder, that would have run down to his hand - and connected them instead into his chest muscles.
The arm was developed by bionics company Otto Bock, in Vienna. The company says this new kind of intelligent prosthetic arm can be controlled using the same nerves in an ordinary arm.
The nerves are connected to the device, which the company says helps to produce more natural movements.
Andy had to spend months learning how to move the arm with his thoughts.
How does it feel?
Since having the special surgery Andy feels as though his hand is in his chest.
He said: "Because obviously I haven't had a thumb or a finger for the last three years, then all of a sudden to start feeling stuff is a total weird feeling so you have got to train your brain to move this hand."
He says it takes a lot of concentration as some thoughts of movement are really powerful: at times, thinking about wiggling his little finger makes his hand spin around a full 360 degrees.
This - he says - is "his party trick".
He says it looks "very natural and people generally do not notice that it is a prosthesis, but are often surprised as it makes robotic sounds when it moves.
Andy also said he was enjoying being able to more around the house and being far more independent.
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