Robotic-arm technology translates thoughts into motion

PITTSBURGH - With mind control, a monkey fed itself marshmallows with a robotic arm. Then one year ago, a man with quadriplegia reached out with a robotic arm to touch his girlfriend's hand.

Now the mind-controlled robotic-arm technology developed at the University of Pittsburgh has reached another milestone. A study published online Monday in The Lancet describes how a 52-year-old woman -- a quadriplegic for nine years -- has spent the past 10 months learning to maneuver the robotic arm with her thoughts, allowing her to pick up objects of various shapes, shake hands, and even grasp a chocolate bar and take a bite.

Jan Scheuermann's accomplishments, resulting from decades of Pitt research, heighten the promise of people with quadriplegia or arm amputations to use mind-controlled robotic arms to perform daily tasks independently. The study also marks an important step in the goal of wiring the brain around spine damage to arm and leg muscles to restore limb function.

"It was pretty spectacular," said Andrew B. Schwartz, the research team leader, describing Scheuermann, as articulate, intelligent and exuberant.

Schwartz noted that the research proves that using a robotic arm to perform daily tasks is feasible. Further advances and refinements are necessary before the technology is available for general use, which could take five years or longer.

Tim Hemmes of Butler County, Penn., was the first to operate the robotic arm with his mind. He had a motorcycle accident eight years ago that left him with quadriplegia, but he underwent a surgical procedure to place a computer chip against his brain that, with training, allowed him to reach out and touch his girlfriend Katie Schaffer's outstretched hand last year.

The process works by translating thoughts via a computer chip to make the robotic arm perform an intended task. The team embedded a computer chip with 200 needles into Scheuermann's brain, each one stationed near a small group of neurons known to control a particular arm or hand motion.

Researchers made technological advances in the past 10 months. Scheuermann, who has had the computer chip imbedded in her brain since February, was able to train quickly to operate the arm, making it easier to reach a target or perform a task. She continues using the device in the yearlong trial that initially was scheduled to end in February. But the U.S. Food and Drug Administration has granted permission to extend it beyond the initial one-year limit, if necessary.

The study says Scheuermann achieved seven degrees of freedom in arm and hand motions, including moving it in the three dimensions of space while also using three different wrist movements and a grasping motion with all the fingers. She learned how to focus on a task, with the arm and hand doing the rest. It reflects how the brain really works. When we decide to pick up a glass, for example, the hand goes to the glass and grasps it. We need not think about bending the shoulder, elbow, wrist and hands at various angles to make it happen. Since the latest study was published, Scheuermann has progressed to 10 degrees of freedom that allow more detailed use of the hand and fingers.

Initially, Scheuermann told researchers her goal was simple. She hoped for the first time in nine years to grasp a chocolate bar and eat it without anyone's help. In the lab, with a student holding the chocolate, she reached and grasped it, then brought it to her mouth and took a bite, then another and still others until the chocolate bar was gone. Able to shake hands, she also grabbed a cup and did a pouring motion.

Lawrence C. Vogel, president of the American Spinal Injury Association and chief of pediatrics at the Chicago Shriners Hospital for Children, described the news as "very exciting" and "incredible."

He also said he's been a strong proponent of Pittsburgh researchers who are doing "super work" on behalf of people with disabilities.

"I think they are doing really cutting-edge research to improve the lives of people with spinal cord injuries," Dr. Vogel said. "This research will translate into allowing people to do more with their lives."

(Contact David Templeton at dtempleton@post-gazette.com.)