Quadriplegic woman’s brain helps operate robotic arm

(TNS)

PITTSBURGH — Jan Scheuermann can beat her brother at rock-paper-scissors.

It wouldn't be so impressive were she not a quadriplegic suffering from spinocerebellar degeneration for more than a decade.

Playing (and winning) that game and much more were possible when researchers connected electrodes in her brain to a robotic arm in a University of Pittsburgh School of Medicine project. Findings were published recently in the Journal of Neural Engineering.

"In this paper we actually split it up so that she can control four different postures of the hand and combine those all continuously, which allows her to perform a lot of different grasp types and hand shapes," said senior investigator Jennifer Collinger, assistant professor in Pitt's Department of Physical Medicine and Rehabilitation.

The research describes for the first time 10-degree (or 10-movement) brain control of a prosthetic device in which the trial participant used the arm and hand to reach, grasp and place a variety of objects, Collinger said. Only seven-degree control had been reached before.

The movements that Scheuermann, 55, of Whitehall, performed that had not previously been accomplished were: finger abduction, in which the fingers are spread out; scoop, where the last fingers curl in; thumb opposition, in which the thumb moves outward from the palm; and a pinch of the thumb, index and middle fingers.

The research required surgical implementation of small electrode grids each with 96 contact points in the regions of Scheuermann's brain that controlled her right arm and hand. Her head hurt after the surgery, but she maintained her sense of humor.

"I named my implants Lewis and Clark because they were exploring uncharted territory," she said.

Each electrode point picked up signals from an individual neuron, which were then relayed to a computer to identify the firing patterns associated with particular observed or imagined movements, such as raising or lowering the arm, or turning the wrist.

Scheuermann watched animations of and imagined the movements while the team recorded the signals her brain was sending in a process called calibration. They then used what they had learned to read her thoughts so she could move the hand into the various positions.

This showed that signals can be interpreted from neurons with a simple computer algorithm to generate sophisticated, fluid movements that allow the user to interact with the environment, according to Collinger.

The project came to an end in October, and Scheuermann had surgery to remove the electrodes. But she doesn't think her mission is complete.

She said she wants to educate people about the research and has spoken to various college and middle and high school groups. She calls her talks "The Lighter Side of Being a Lab Rat." She is also currently using a dictation system to write a book about her experiences in the Pitt research.

The research may never benefit Scheuermann and may not help others with movement difficulties for years. Collinger said that a more robust device that patients could use in their homes is at least five years away. But this work shows that as research continues there is definite hope for the future.

"When people hear about this they have hope," Scheuermann said. "And they have hope that something is being done even if it won't benefit them."

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