A new device that reads thoughts and converts them into machine commands is showing promise in re-training injured brains and reversing paralysis in stroke victims. Ben Gruber reports.
STORY: After three strokes that left the right side of his body paralyzed, Rick Arnold told his wife Kim that he had just one wish. (SOUNDBITE) (English) RICK ARNOLD, STROKE PATIENT, SAYING: "All I really wanted to do was to be able to hold her hand. In the very beginning, it was to hold her hand. I can do that now." He can do that now thanks to a new device that could potentially change the rules on how well stroke victims recover. Arnold is using brain-machine interface technology developed by Eric Leuthardt, a neurosurgeon at Washington University in St. Louis. After years of research, Leuthardt discovered that the rule that one side of the brain controls the opposite side of the body isn't set in stone. He says that the thought or intention to move could be derived from other parts of the brain. (SOUNDBITE) (English) DR. ERIC LEUTHARDT, NEUROSURGEON, WASHINGTON UNIVERSITY, SAYING: "In a stroke patient they have had an injury to one side of their brain that causes their hand to be paralyzed. So we are taking a signal from the uninjured side of the brain, the opposite side of the brain, decoding that intention to move that even though they can't move we know that they want to move." That thought of wanting to move is then converted into a machine command which is sent to an exoskeleton device that moves Arnold's hand. This is where the brain's plasticity comes into play. Leuthardt says that by using the device, the brain can be re-wired and re-trained to compensate for its injured parts. (SOUNDBITE) (English) DR. ERIC LEUTHARDT, NEUROSURGEON, WASHINGTON UNIVERSITY, SAYING: "We are using external circuitry, meaning that we are using this brain-computer interface and this exoskeleton which gets controlled by your brain to alter the internal circuitry." Arnold has recovered better than anyone expected and continues to improve every day. That, says Leauthardt, confounds the other classic notion that people can't recover more than six months after a stroke. (SOUNDBITE) (English) DR. ERIC LEUTHARDT, NEUROSURGEON, WASHINGTON UNIVERSITY, SAYING: "Rick was three to four years out from his stroke and we can still recharge his plasticity for him to change his brain circuitry to functional improvement." (SOUNDBITE) (English) RICK ARNOLD, STROKE PATIENT, SAYING: "Every day is Christmas. It's all working, it's just falling into place the way you want it to be. ..I am going way beyond anyone thought including myself thought would get his better, much better." Arnold says that every day presents a new obstacle, but now that his wish came true and he's holding his wife's hand again, he's up for any challenge.