Monkeys Use Brain Power to Control Artificial Arm
Steve Connor Science Editor, The Independent (London, England)
A BRAIN implant has allowed animals to control a robot arm by thought alone in a study that raises the prospect of helping paralysed people who cannot use their limbs.
Scientists from Duke University in North Carolina said yesterday that the implants permitted laboratory monkeys to manipulate a mechanical arm using brain signals.
The primates learnt that to move the robot, they had to think about doing so. This is the first time scientists have demonstrated the possibility of controlling an artificial limb as if it were part of the body.
During the study, tiny electrodes implanted into the brain of each monkey transmitted electrical signals to a computer controlling the movements of the robotic arm, via hair-thin wires running from the skull of the animal.
At first, the monkeys were trained to control the robot arm using a joystick. When this was deactivated, the animals could still move the mechanical arm by thinking about moving the joystick in the appropriate way, said Miguel Nicolelis, professor of neurobiology at Duke University.
"The most amazing result was that after a few days the monkey suddenly realised that she didn't need to move her arm at all," Professor Nicolelis said.
"Her arm muscles went completely quiet and she controlled the robot arm using only her brain and visual feedback. Our analyses of the brain signals showed that the animal learnt to assimilate the robot arm into her brain as if it was her own arm."
The research, published in the new online science journal Public Library of Science, is one of the latest of a string in scientific studies in which animals have learnt to operate simple devices via subtle electronic signals from the brain. …