Good news for the amputees. Scientists from the Swiss Federal Institute of Technology in Lausanne (EPFL) have successfully developed a bionic fingertip that can make the amputees not only feel textures but also differentiate between rough and smooth surfaces. Aabo Sørensen, a property developer in Aalborg, Denmark was the first to test it out. Nine years ago, he lost his left hand in a fireworks accident.
Scientists attached the bionic finger to the end of his arm where it was amputated. They wired the nerves to that artificial fingertip equipped with sensors in his arm. The movement of the fingertip over different pieces of plastics was controlled by a machine. The plastics were carved with different patterns, both smooth and rough. The sensors then produced an electrical signal that was converted into a series of electrical spikes, following the language of the nervous system, and then delivered to the nerves.
“The stimulation felt almost like what I would feel with my hand,” said Sørensen about the artificial fingertip connected to his stump. “I still feel my missing hand, it is always clenched in a fist. I felt the texture sensations at the tip of the index finger of my phantom hand.”
The same experiment was performed on non-amputees, where no surgery was needed. the researchers delivered the tactile information through fine needles temporarily attached to the arm’s median nerve through the skin. They were able to differentiate between roughness in texture 77% of the time while Sørensen could do it 96% of the time.
The researchers were able to prove that the fingertip is able to activate the same parts of the brain that the real fingers do. Besides providing the amputees the artificial finger with real touch, the scientists are also thinking that this creation could give rescue, surgical, and industrial robots the power of artificial touch.