In a first of its kind study, U.S. reseachers have been able to get animals to move paralyzed muscles using an experimental device stimulated by brain cells. As VOA's Jessica Berman reports, investigators say the research offers hope to people who are paralyzed as a result of spinal cord injuries.
Using a computer device hooked up to cells in the brains of monkeys, researchers at the University of Washington found the primates, whose arms were temporarily paralyzed, were able to move their immobilized muscles well enough to play a computer game.
The nerves were located in the motor cortex, the area of the brain responsible for movement. But the scientists tested other nerve cells in the brain.
Chet Moritz is lead author of the study appearing this week in the journal Nature.
In a teleconference with reporters describing the work, Moritz says investigators found that neurons that had nothing to do with movement, including those responsible for the senses, worked just as well.
"We found remarkably that nearly every neuron that we tested in the brain could be used to control this type of stimulation," he said. "We also found that monkeys could learn very rapidly to control newly isolated neurons in order to stimulate their muscles."
Researchers say two-thirds of the neurons they tested produced movement.
Experts say previous research into paralysis has focused on using a computer interface to record brain activity and to feed it into a prosthetic arm.
Co-author Eberhard Fetz, a professor of physiology and biophysics at the University of Washington, says the new experiments are different.
"The big strategy here is to work with the muscles in the intact arms instead of artificial robotic arms or other devices other people have shown can be controlled, but may not be so practical," he said.
The researchers envision paralyzed individuals acquiring the ability to pick up a coffee mug.
Investigators say their next step is to come up with an implantable computer device without wires, which could take years if not decades to develop before the technology is available for human trials.
