PHILADELPHIA -- Researchers at MCP Hahnemann University and Duke University have developed a method for recording brain signals onto electrode arrays in laboratory rats that enable the rats to control a robotic arm without any actual muscle movement.

According to the scientists, the achievement demonstrates the likelihood that electrodes may someday be implanted into the brains of humans who have lost limb function, allowing them to control a prosthetic device as they would their own biological limbs. The study is being published in the July 1 issue of Nature Neuroscience.

In experiments, rats were trained to control a robotic arm by pressing a lever to receive a reward. During the rats' lever-pressing, the researchers used arrays of electrodes implanted in the rats' brains to record the simultaneous activity of dozens of neurons in the areas that control muscle movement.

"Identifying which neurons in the brain are responsible for moving the robotic arm was key to our success," said John Chapin, professor of neurobiology and anatomy at MCP Hahnemann University. "Previously, researchers have focused on single neurons in the motor systems. We took a broader look and found that if we could recreate the many signals sent by dozens of neurons at the same time, we could essentially program the movement into the brain."

Once the data were recorded, researchers switched control of the reward from the lever to the implanted electrodes. The rats quickly learned to move the robotic arm to receive the reward solely through brain activity, without actually moving their muscles.

"We were quite surprised that the animals so readily learned that they did not need to actually make the movement to operate the robot; that they only needed to express the brain wave pattern," said Dr. Miguel Nicolelis of Duke University Medical Center, one of the researchers.

"This study breaks new gro
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Contact: Russell Rickford
215-895-2617
Duke University
22-Jun-1999