A man who was paralysed from below the neck after crashing his bike into a truck can once again drink a cup of coffee and eat mashed potato with a fork, after a world-first procedure to allow him to control his hand with the power of thought.
Bill Kochevar, 53, has had electrical implants in the motor cortex of his brain and sensors inserted in his forearm, which allow the muscles of his arm and hand to be stimulated in response to signals from his brain, decoded by computer. After eight years, he is able to drink and feed himself without assistance.
Kochevar underwent brain surgery to implant sensors in the motor cortex area responsible for hand movement, linked to a computer. He then went through four months of training, thinking about the turn of the wrist or grip of the fingers that he needed in order to bring about the movement of a virtual reality arm, so that the computer could recognise the necessary signals from the motor cortex.
Then he had 36 muscle-stimulating electrodes implanted into his upper and lower arm, including four that helped restore finger and thumb, wrist, elbow and shoulder movements. These were switched on 17 days after the procedure, and began stimulating the muscles for eight hours a week over 18 weeks to improve strength, movement and reduce muscle fatigue.
Then the whole system was connected up, so that signals from the brain were translated via a decoder into electrical impulses to trigger movement in the muscles and nerves in his arm.