When you lose the use of a limb, even the simplest of daily tasks can turn into a challenge. High-tech devices can help restore independence. New technologies are even making it possible to connect the mind to an artificial limb. These artificial limbs are called bionic prosthetic devices.
Traditional prosthetic devices use a body-powered harness to control a hand device. These are easy to use. With a shrug of your shoulder, the prosthetic hand or hook opens. With the release of your shoulder, the prosthesis closes. Through the feel of the cable tension across your shoulders, you know whether the prosthesis is open or closed without looking at it.
Newer, motorized hands are not as easy to learn how to use. To close the device, you contract the remaining muscles in your arm. An electrical sensor placed over those muscles detects the contraction and tells the hand to close. Since the original muscles that controlled the hand are gone, the remaining muscles must be retrained. Learning how to open and close a prosthetic hand in this way takes some time. And you still need to watch the device to know what it’s doing.