M.D./Ph.D. student and GRIDLab member David Caldwell tests the hardware used for stimulating and recording a patient’s brain surface, along with a cyber glove to track hand joint angles and finger motions. Photo: Mark Stone, University of Washington.
M.D./Ph.D. student and GRIDLab member David Caldwell tests the hardware used for stimulating and recording a patient’s brain surface, along with a cyber glove to track hand joint angles and finger motions. Photo: Mark Stone, University of Washington.

In a study to be published this month, University of Washington researchers announce a promising discovery: electrodes placed on the surface of the brain could help those with spinal cord injuries recover a sense of ‘touch feedback,’ an essential element in reversing paralysis.

The study, which was conducted by a team of bioengineers, computer scientists and medical researchers from the National Science Foundation’s Center for Sensorimotor Neural Engineering and UW’s GRIDLab, worked with patients who had a grid of electrodes placed on the surface of their brain — more powerful than electrodes on the scalp, but less intrusive than implanting electrodes in the brain itself.

The electrodes were then attached to a glove laced with sensors. The sensors created sensory feedback by prompting more intense electrical signals on a patient’s brain when their hand was more closed, and less intense signals when their hand was more open. Researchers tested the patient’s ability to sense how open or closed their hand was based on this sensory feedback.

The study found that patients could use the feedback system to determine the position of their hand, an essential issue in returning movement to patients with spinal cord injuries.

The electrocorticography (ECoG) grid, which was used in the study. The grid is implanted in patients about to undergo epilepsy surgery, who agreed to work with scientists for this researc. Photo: Mark Stone, University of Washington.
The electrocorticography (ECoG) grid, which was used in the study. The grid is implanted in patients about to undergo epilepsy surgery, who agreed to work with scientists for this research. Photo: Mark Stone, University of Washington.

“To our knowledge this is the first time it’s been done in a human patient who was awake and performing a motor task that depended on that feedback,” lead author and UW bioengineering doctoral student Jeneva Cronin said in a statement.

Although technologies exist that can return movement to patients with paralysis, there is less tech that would help patients guide that movement. Without sensory feedback, patients would not be able to tell how hard they were gripping an item, for example.

These findings are notably different from efforts at the University of Pittsburgh, highlighted at this month’s White House Frontier Conference. In that research, electrodes were implanted directly in a patient’s brain and connected to a robotic hand.

The patient studied in Pittsburgh was essentially able to ‘feel’ what was happening to the robotic hand, as his sense of touch was directly stimulated. But in the UW study, patients did not ‘feel’ their hands in the same way.

“The question is: Can humans use novel electrical sensations that they’ve never felt before, perceive them at different levels and use this to do a task? And the answer seems to be yes,” co-author and UW bioengineering doctoral student James Wu said in a statement. “Whether this type of sensation can be as diverse as the textures and feelings that we can sense tactilely is an open question.”

Although the sensations are not the same as our natural sense of touch, this system is much less intrusive than the one studied in Pittsburgh. The early success of this sensory feedback method could be key to future developments in returning movement to those with paralysis.

Like what you're reading? Subscribe to GeekWire's free newsletters to catch every headline

Job Listings on GeekWork

Find more jobs on GeekWork. Employers, post a job here.