The two collaborated with clinical centers at Stanford and the University of Utah, and with researchers at the Cleveland Clinic. Dr. Jaimie M. Henderson, a neurosurgeon at Stanford, performed the surgery, and the team is recruiting other candidates in the Bay Area to see if the procedure is viable for other people with moderate to severe traumatic brain injuries.
In the operation, performed last summer, Dr. Henderson threaded two electrodes into the thalamus, a switching center deep in the brain. Precision was critical. Before the surgery, the team did extensive work to identify specific regions in the brain that support activation of the frontal cortex, which is involved in thinking and planning, and the basal ganglia, which supports learning and memory.
“Operating on the thalamus is pretty routine,” Dr. Henderson said in an email. “This is a different target, though, and difficult to hit because of its size and shape. So a bit of extra precision is called for.”
The electrodes were connected to a pacemaker device, implanted in the woman’s chest wall, that produced active current for 12 hours a day, from morning to evening.
The woman improved gradually, and by three months was consistently scoring about 15 percent better than she had previously on standardized tests of attention, planning and executive function. She also reported 70 percent less fatigue on a standard measure, and no longer took daily afternoon naps, as she had before, the researchers reported.
At one point during her rehabilitation, the pacemaker accidentally failed, and her gains tapered off. Doctors quickly restored the current, and her ability improved.
About one in five people with similar injuries receive some continuing treatment. This often includes cognitive therapy — typically, computer-based training for attention and memory, an hour a week for 12 weeks — and many see gradual improvements. But that therapy is not easy to access, and insurers don’t always pay for it.