Tuesday, January 8, 2008
Researchers at Duke University and MCP Hahnemann University have developed a technique for using brain signals to control a robotic arm. This feat was accomplished by recording signals from electrodes that were implanted in the brains of rats. It is believed that this new method may some day offer hope to those suffering from spinal cord injuries who have prosthetic limbs. Theoretically, the electrodes could be implanted into the brain to allow the person to have control over limb movement, much as they would an actual limb. In the experiment, rats were taught to operate a robotic arm by pressing a lever. Pressing the lever resulted in the rats receiving a reward. Researchers recorded the neuronal activity responsible for muscle movement using implanted electrode arrays. Once the specific groups of neurons that were used for muscle movement when pressing the lever were identified, researchers changed the control of the robotic arm from the lever to the electrode implants. The rats promptly learned that they could move the robotic arm to receive a reward without having to press the lever. All they had to do was to activate the particular neurons in the brain that they had previously used when physically pressing the lever. This ground-breaking study established the first tangible evidence that neuron signals can be used to control external devises. Prior to this study, scientists suspected that neuronal control of external devices was possible but there was no demonstrable proof. Researchers speculate that the knowledge gained from this study could be used to develop new techniques to treat those suffering from a variety of disabilities including spinal cord injuries, cerebral palsy, and locked-in syndrome. Since those with locked-in syndrome may have intact thinking skills but no ability to interact with their environment, external control of devices through neurons may be particularly helpful. The researchers also strongly emphasize that there are still significant technical obstacles that must be overcome before any attempts at human clinical trials can begin. They do however believe that these obstacles are not impossible to overcome.
Posted by Mayank at 5:44 AM