Team describes findings from BCI study in spinal cord-injured man in PLoS One

Researchers at the University of Pittsburgh School of Medicine and UPMC describe in PLoS ONE how an electrode array sitting on top of the brain enabled a 30-year-old paralyzed man to control the movement of a character on a computer screen in three dimensions with just his thoughts. It also enabled him to move a robot arm to touch a friend's hand for the first time in the seven years since he was injured in a motorcycle accident.

With brain-computer interface (BCI) technology, the thoughts of Tim Hemmes, who sustained a spinal cord injury that left him unable to move his body below the shoulders, were interpreted by and translated into intended movement of a and, later, a robot arm, explained lead investigator Wei Wang, Ph.D., assistant professor, Department of Physical Medicine and Rehabilitation, Pitt School of Medicine.

"When Tim reached out to high-five me with the robotic arm, we knew this technology had the potential to help people who cannot move their own arms achieve greater independence," said Dr. Wang, reflecting on a memorable scene from September 2011 that was re-told in stories around the world. "It's very important that we continue this effort to fulfill the promise we saw that day."

Six weeks before the implantation surgery, the team conducted (fMRI) of Mr. Hemmes' brain while he watched videos of arm movement. They used that information to place a postage stamp-size electrocortigraphy (ECoG) grid of 28 recording electrodes on the surface of the brain region that fMRI showed controlled right arm and hand movement. Wires from the device were tunneled under the skin of his neck to emerge from his chest where they could be connected to computer cables as necessary.

For 12 days at his home and nine days in the research lab, Mr. Hemmes began the testing protocol by watching a virtual arm move, which triggered that were sensed by the electrodes. Distinct signal patterns for particular observed movements were used to guide the up and down motion of a ball on a computer screen. Soon after mastering movement of the ball in two dimensions, namely up/down and right/left, he was able to also move it in/out with accuracy on a 3-dimensional display.

"During the learning process, the computer helped Tim hit his target smoothly by restricting how far off course the ball could wander," Dr. Wang said. "We gradually took off the 'training wheels,' as we called it, and he was soon doing the tasks by himself with 100 percent brain control."

The was developed by Johns Hopkins University's Applied Physics Laboratory. Currently, Jan Scheuermann, of Whitehall, Pa., is testing another BCI technology at Pitt/UPMC.

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

What happens in our brain when we unlock a door?

13 hours ago

People who are unable to button up their jacket or who find it difficult to insert a key in lock suffer from a condition known as apraxia. This means that their motor skills have been impaired – as a result ...

Sport can help multiple sclerosis patients

16 hours ago

A study developed at the Miguel Hernández University of Elche (Spain) has preliminarily concluded that people with multiple sclerosis may reduce perceived fatigue and increase mobility through a series of ...

Obama's BRAIN initiative gets more than $300 million

21 hours ago

President Barack Obama's initiative to study the brain and improve treatment of conditions like Alzheimer's and autism was given a boost Tuesday with the announcement of more than $300 million in funds.

User comments