A little electric stimulation in just the right spot may bolster a damaged brain

When Gina Arata was 22, she crashed her car on the way to a wedding shower.

Arata spent 14 days in a coma. Then she spent more than 15 years struggling with an inability to maintain focus and remember things.

"I couldn't get a job because if I was, let's say, a waitress, I couldn't remember to get you a Diet Pepsi," she says.

That changed in 2018, when Arata received an experimental device that delivered electrical stimulation to an area deep in her brain.

When the stimulation was turned on, Arata could list lots of items found in, say, the produce aisle of a grocery store. When it was off, she had trouble naming any.

Tests administered to Arata and four other patients who got the implanted device found that, on average, they were able to complete a cognitive task more than 30 percent faster with stimulation than without, a team reports in the journal Nature Medicine.

"Everybody got better, and some people got dramatically better," says Dr. Jaimie Henderson, an author of the study and neurosurgeon at Stanford University.

The results "show promise and the underlying science is very strong," says Deborah Little, a professor in the Department of Psychiatry and Behavioral Sciences at UT Health in Houston.

But Little, who was not connected with the research, adds, "I don't think we can really come to any conclusions with [a study of] five people."

From consciousness to cognition

The study emerged from decades of research led by Dr. Nicholas Schiff, an author of the paper and a professor of neurology and neuroscience at Weill Cornell Medicine in New York.

Schiff has spent his career studying the brain circuits involved in consciousness.

In 2007, he was part of a team that used deep brain stimulation to help a patient in a minimally conscious state become more aware and responsive. Nearly a decade later, he teamed up with Henderson to test a similar approach on people like Gina Arata.

Henderson was charged with surgically implanting tiny electrodes deep in each patient's brain.

"There is this very small, very difficult-to-target region right in the middle of a relay station in the brain called the thalamus," Henderson says.

That region, called the central lateral nucleus, acts as a communications hub in the brain and plays an important role in determining our level of consciousness.

The team hoped that stimulating this hub would help patients like Arata by improving connections with the brain's executive center, which is involved in planning, focus, and memory.

So starting in 2018, Henderson operated on five patients, including Arata. All had sustained brain injuries at least two years before receiving the implant.

"Once we put the wires in, we then hook the wires up to a pacemaker-like device that's implanted in the chest," Henderson says. "And then that device can be programmed externally."

The improved performance with the device suggests that it is possible to "make a difference years out from injury," says Little, who is research director at the Trauma and Resilience Center at UT Health.

If deep brain stimulation proves effective in a large study, she says, it might help a large number of brain injury patients who have run out of rehabilitation options.

"We don't have a lot of tools to offer them," Little says, adding that "even a 10 percent change in function can make the difference between being able to return to your job or not."

Arata, who is 45 now, hasn't landed a job yet. Two years ago, while studying to become a dental assistant, she was sidelined by a rare condition that caused inflammation in her spinal cord.

But Arata says the implanted stimulator she's had for five years allows her to do many things that had been impossible, like reading an entire book.

"It's on right now," she says during a chat on Zoom. "It's awesome."

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