Article and more video (don’t miss! the monkey manipulates the arm so he can lick the fingers):

In a dramatic display of the potential of prosthetic arms, a monkey at the University of Pittsburgh was able to use his brain to directly control a robotic arm and feed himself a marshmallow. The research, published today in the journal Nature, is the first to show that an interface that converts brain signals directly into action is sophisticated enough to perform a practical function: eating. Researchers who led the work have just begun human tests of a related technology.