Brain research could help patients with paralysis move again

On a Friday morning at Pennsylvania Hospital, Gail Martin rested on an operating room table, the top of her head encased in what looked like a clear plastic bubble and her left hand fitted with a Hollywood-style motion capture glove.

Every few seconds, Martin moved her hand to mimic the gesture that appeared on a screen in front of her. All the while, two sets of electrodes placed in and on Martin's brain recorded what she was thinking with each specific movement.

The data collected have the potential to revolutionize care for patients with paralysis, as researchers ask: "What if we could use machine learning to translate brain waves into physical actions and give paralyzed patients the ability to move again?"

"I've been thinking about this idea of restoring function with devices for patients with paralysis for a long time," says Iahn Cajigas, an assistant professor of neurosurgery and bioengineering. "It's incredible that we're now at this cusp of new technologies that are going to facilitate understanding how the brain works and potentially translating that to our patients."

As a physician scientist, Cajigas uses deep brain stimulation (DBS) to treat patients with Parkinson's disease or other forms of tremor for which medications are no longer helpful-patients like 71-year-old Martin, whose tremors have gotten so bad she can barely walk or play with her grandchildren.

With DBS, electrodes are surgically placed in targeted areas deep inside the brain and attached to a neurostimulator implanted in the patient's chest, like a pacemaker for the brain. This eventually allows for electrical impulses to be sent to the electrodes, stimulating changes in the brain that reduce tremors and other symptoms.

It also allows Cajigas to study the areas of the brain-in patients who volunteer to participate-that control movement. Access to the brain is necessary for the type of research Cajigas is conducting, so his role in a busy DBS clinic where patients have already opted for brain surgery is helping to make the project possible. Other studies that have less access to patients are somewhat limited.

"In our approach, we're actually leveraging the fact that we're a very busy clinical center for DBS," Cajigas said. "It'd be very challenging to study this system at all, outside of this limited context. You're not going to find healthy volunteers who are willing to allow you to put electrodes deep into the brain, like DBS requires."

Colleague Bijan Pesaran, the Robert A. Groff, MD Professor of Neurosurgery and professor of bioengineering and neuroscience, agreed that the volume of patients Cajigas is able to study helps accelerate the pace of research.

"Instead of looking at one subject every few years or every year or so, we can study a different patient each week or each month," Pesaran says.

This story is by Kim Maialetti. Read more at Penn Medicine News.