Researchers have moved a step closer to creating workable neural prostheses, following the identification, in monkeys, of the brain signals the lead to motion. They have also been able to use those signals to trigger the same movement in a robot in real time.

Previous work in the area has involved a time delay between intercepting the signals and instigating robotic movement.

"As the monkey brain prepares the pattern required to make the movement, we record it and send the signal to a computer," Dr. Miguel Nicolelis, a neuroscientist at Duke University, said. "As the monkey starts to move, our prediction is sent to the robot, and it moves at the same time."

The long term goal of research like this is to develop proper brain to machine interfaces that would allow paralysed people to walk again. The idea behind this is that even if the movement is no longer possible, the brain may still plan a motion. If this is so then eventually someone paralysed from the waist down could use technology like this to walk.

The next step, the researchers said, would be to close the loop. They speculate that eventually a monkey may learn to use a remote robot to do its bidding, without actually carrying out the motions itself.

Once perfected, it could be used by surgeons as they learn to use a prosthetic device as an extension of their bodies.

That, however, is still a long way off the researchers say. The "small" problem of miniaturising and implanting the electrodes still remains to be solved. ®