Bionic body parts might seem like the stuff of science fiction movies, television, and comics, but restoring the use of body parts for amputees is a high priority in both civilian and military contexts. Bionics research is slowly becoming more reality than fiction, though, with recent studies having success with everything from bionic eyes to bionic legs. Making these bionic parts with a sense of touch has proven tricky, but a team of European scientists have found success: they've created a bionic hand that allows for the sense of touch in real-time, offering significant new capabilities to amputees.
Dennis Aabo Sørensen lost his hand in a fireworks accident nine years ago. With the use of a new type of bionic hand he's regained the ability to feel objects, sensing their size, shape, and even texture. Scientists began by surgically implanting transneural electrodes into the remaining nerves in Sørensen’s damaged arm, which relay electrical signals into his body’s nervous system. This is the first time that scientists have implanted electrodes like this that are capable of working regardless of signal strength, or after scar tissue has formed.
After they implanted the electrodes, the team attached a prosthetic arm equipped with touch-detecting sensors to the electrodes. During a touch, the sensors generate electrical signals, and a computer algorithm converts those signals into nerve impulses. As the nerve impulses travel from the electrodes implanted in Sørensen’s arm, his nervous system tells him that he’s touching or moving something.
Sørensen described the effect of using his new arm as "incredible." After scientists blindfolded him and made him wear ear plugs, he could still successfully pick up objects: touching them, feeling their textures, determining how strongly he was holding them, and even feeling what shape or size they were. Considering that his nerves hadn’t been used in nine years, scientists consider these results astounding.