Having been in the military for twenty years, I’m very sympathetic to anyone who has lost a limb. Great progress has been made in fabricating lifelike and functional prosthetics, but they still have one major disadvantage — feeling. There is no sensation in metal and plastic. So the only way to control an artificial hand, for example, has been to watch it and adjust accordingly.
But this may now been changing too. There’s news of artificial limbs that can provide sensations to the wearer. The latest issue of Science Translational Medicine describes how researchers have developed a neural interface that mimics feedback through a prosthesis, restoring feeling in test subjects with upper limb amputations. Not only can patients improve their control of a robotic hand, but they can also perceive its movements, like wrapping fingers, even when blindfolded. “We’ve tapped into people’s perceptual integration system,” says Paul Marasco, a neuroscientist and sensorineural physiologist at the Cleveland Clinic.
The awareness of movement and position of a body part is called kinesthesia. This is what lets you pick up a book with your right hand while staring at a phone in your left. The sensation is commonly regarded as a sixth sense. The details get a bit complex, but now people with prosthetics have the opportunity to regain this lost sense.
To learn more, see “Researchers Restore Elusive Sixth Sense to Lost Limbs” by Robbie Gonzalez (https://www.wired.com/story/researchers-restore-feeling-to-lost-limbskinda/). The photo is from that site.