Prosthetic medicine

ARTIFICIAL limbs are nothing new. An ersatz toe, made of wood and leather and found attached to the mummified body of an Egyptian noblewoman in Cairo, in 2000, is thought to be between 2,500 and 3,000 years old. Things have moved on since then. Modern prostheses sport things like articulated fingers that can be controlled by picking up impulses from their wearer’s remaining nerves.

But a bionic limb receiving commands is only half the picture. To be a true replacement, it should also be able to send sensations back to its wearer, to enable him to control it precisely. And, in a study just published in Science Translational Medicine, a group of researchers led by Robert Gaunt, an engineer at the University of Pittsburgh, have taken an important step towards this goal. Their paper describes a way of restoring sensation by using implanted electrodes to stimulate a patient’s brain directly.

The patient in question is a 30-year-old man whose spinal cord was damaged in a car crash. He is not an amputee, but his injury means his brain and his hands can no longer communicate. Dr Gaunt’s aim was, first, to create an illusion in the patient’s brain that this was not the case, and then to use that illusion to send to that brain signals from an artificial hand which was equipped with sensors on its fingers.

Sensations from the…Continue reading
Source: Economist