It's not quite the bionics of science fiction, but European researchers have created a robotic hand that gave an amputee a sense of touch he hadn't felt in a decade.
The experiment lasted only a week, but it let the patient feel if different objects - a bottle, a baseball, some cotton, a mandarin orange - were hard or soft, slim or round, and intuitively adjust his grasp.
It will take years of research before an artificial hand that feels becomes a reality.
But the research released on Wednesday is part of a major effort to create more lifelike and usable prosthetics.
"It was just amazing," said Dennis Aabo Sorensen of Aalborg, Denmark, who lost his left hand in a fireworks accident and volunteered to pilot-test the bulky prototype.
"It was the closest I have had to feeling like a normal hand."
The experiment is among the most advanced, essentially creating a loop that lets the robotic hand rapidly communicate with Sorensen's brain so he could feel and react in real time.
Scientists have made great strides in improving the dexterity of prosthetics, but the sense of touch has been a much more difficult challenge and is one reason many patients don't use their prosthetic hands as much as they would like.
Users of prosthetic hands have to carefully watch every motion, judging by eye instead of touch how tightly to squeeze. The results can be clumsy, with dropped dishes or crushed objects.
Doctors at Rome's Gemelli Hospital implanted tiny electrodes inside two nerves in the stump of Sorensen's arm.
When researchers zapped them with a weak electrical signal, Sorensen said it felt like his missing fingers were moving, showing the nerves still could relay information.
Meanwhile, Micera's team put sensors on two fingers of a robotic hand to detect information about what the artificial fingers touched.
"Suddenly I could tell if it was a hard object," Sorensen said.
"The response, the feedback from the arm to my nerves and to my brain, they came very strong."
