As the intersection between medicine and technology grows ever stronger, so too has the possibility of (at least partially) bionic human beings. Prosthetic devices have moved beyond serving a purely aesthetic purpose, and are now indeed replacing limbs in almost every sense of the word. And now that includes sensation.
In a groundbreaking achievement, scientists from the École Polytechnique Fédérale de Lausanne in Switzerland have allowed an amputee to actually “feel smoothness and roughness in real-time with an artificial fingertip.” No longer does the loss of certain limbs mean the loss of one of the five senses — rather, by surgically connecting the artificial finger to nerves in the patient’s upper arm, researchers were able to replace the ability to feel textures.
“The stimulation felt almost like what I would feel with my hand,” amputee Dennis Aabo Sørensen said about the artificial fingertip. And while the patient noted that he still feels his missing hand, he was able to discern “texture sensations at the tip of the index finger of my phantom hand.” This makes Sørensen the first person ever to use a bionic fingertip to recognize textures, researchers say.
The feat was achieved through a series of sensors attached to the artificial fingertip. When Sørensen moved the bionic digit over different pieces of plastic that were either smooth or rough, the sensors created an electrical signal that was then “translated into a series of electrical spikes, imitating the language of the nervous system,” that were in turn fed to the existing nerves in his upper arm. Amazingly, Sørensen correctly distinguished between textures 96 percent of the time.
While a fingertip may seem like small potatoes to some, scientists believe that the implications of this breakthrough are boundless. “This study merges fundamental sciences and applied engineering: it provides additional evidence that research in neuroprosthetics can contribute to the neuroscience debate, specifically about the neuronal mechanisms of the human sense of touch,” says Calogero Oddo of the BioRobotics Institute of SSSA. “It will also be translated to other applications such as artificial touch in robotics for surgery, rescue, and manufacturing.”