Roborilla

Using only its brainpower, a monkey could direct a robotic arm to pluck a marshmallow from a skewer and stuff it into its mouth. Great, the dawn of cyber-apes is upon us.

The technology behind this feat may lead to brain-powered prosthetic limbs for people with spinal cord injuries or disabling diseases that make such simple tasks impossible. Or make our simian brothers nigh unstoppable. Until now, such brain-machine interfaces have been used to control cursor movements on a computer screen.

To operate the motorized appendage, monkey guides the robot arm the same way it does its natural limbs, through brain signals. The signals are transferred through an array of microelectrodes half the size of a thumbtack that has been implanted in the monkey's brain, then amplified and relayed to a computer that operates the robotic arm. Certain motor neurons fire rapidly when the monkey wants to move a certain way.

The researchers said it takes about three days for a monkey to learn to operate the arm, and they continuously improve. So far, they have trained two monkeys to feed themselves with the robotic arm. The monkeys sit in a chair with their arms gently restrained in sleeves that keep them from simply grabbing the food on their own. The monkeys appear to enjoy the task, but just wait until they rise against the humans.

Now that the system appears to function, the scientists seek to refine the system by developing an operating wrist and jointed fingers to add dexterity to the device.