Pittsburgh area mom makes medical history with robotic arm
Jan Scheuermann described the start of her disease as feeling like her legs were dragging behind her. Sometimes it was the left, sometimes it was the right.
Eventually, because of an autoimmune disease called spinocerebellar degeneration, she lost movement in her legs, then her arms. Within two years, she was in a wheelchair. Within four, she was a quadriplegic.
For the past several years, the 55-year-old Whitehall mother of two has been making medical history at the University of Pittsburgh by using her mind to move a robotic arm up, down, left, right, in, out and moving a robotic hand to make grasping motions. And in a study published Tuesday in the Journal of Neural Engineering, Scheuermann has taken it one step further by moving the robotic hand in several different ways.
“It's been amazing,” she said. “In a few years, there will be so many people in the world doing this.”
In 2012, a team led by Jennifer Collinger and Andrew Schwartz implanted two devices in Scheuermann's motor cortex, the part of the brain that controls motion. The devices each contained 100 electrodes that allowed the research team, and a computer, to record what brain cells were active when Scheuermann thought about moving. She came into the lab several times per week. First, she'd watch as the computer made the arm move, in one case, from left to right. Then, she'd imagine making the movement, and the computer would record the firing pattern in her brain.
“I was tensing the muscles in my mind,” she said, knowing that her actual arm wouldn't move. “I was thinking right, right, right and I was pushing my mind to do it.”
Then, she would start thinking about moving the robotic arm. At first, the computer would help her move the arm, but after several tries, it was all Scheuermann's brain. In the latest study, said Collinger, with a hand that had independently moving fingers, Scheurmann was able to perform fine movements like spreading the robotic fingers, wiggling the thumb and making a pinching motion. She also made progress on being able to grasp an object and move it from one place to another.
“It's definitely difficult,” Collinger said. “We really tried to push the boundaries of performance.”
The robotic arm was developed at Johns Hopkins University. The funding came from DARPA, the Defense Advanced Research Projects Agency. Scheuermann finished her trials in October, knowing that the advances she has made in the past few years will probably not benefit her. The system needs a lot of human interaction, and it's not wireless. Collinger said that 200 electrodes aren't enough to transmit the most stable, consistent signal. A lot of work lies ahead in the world of mind-controlled prosthetics, said Collinger, and Scheuermann has been a critical part of the process.
“We need someone who...is willing to come into the lab and willing to be very brave and try this new technology,” Collinger said. “It is challenging.”
Megha Satyanarayana is a staff writer for Trib Total Media. She can be reached at 412-320-7991 or firstname.lastname@example.org.