A High-Tech Way to Boost Stroke Recovery
Date: November 1, 2011
Robots and video games probably aren’t the first things to come to mind when you think of strokes. But that may change if ambitious research by Johns Hopkins neurologist John Krakauer pans out. Krakauer is gathering evidence that a course of high-tech rehabilitation therapy, if applied quickly and intensively, can restore much of the function lost to a stroke. “There’s a limited window of time to act after a stroke,” he says. “Within it, we can get amazing degrees of recovery.”
The standard form of rehabilitation treatment for an acute stroke is two weeks in a rehabilitation unit for three hours of therapy a day, followed by a limited number of therapist visits to the home. “That’s too little, too late,” says Krakauer. “And it’s focused not on recovering lost function, but on compensating for it with remaining function.” Patients who lose the use of one arm, for example, are trained to rely more heavily on the other arm.
But neuroscientists know from animal data, notes Krakauer, that a great deal of function can be recovered by repeating tasks that rely on lost function at least 400 times—if the therapy is applied during the brief time after a stroke when the brain is more susceptible to changes. In humans, that window is three months. Ideally, stroke patients would be pushed to repeat critical tasks all day long by therapists. But since that would be too costly, Krakauer envisions placing patients in front of a special video game that prompts them to work on the needed tasks, assisted by a robotic system that ensures the motions are repeated correctly. The therapy would also include transcranial direct current stimulation, in which a mild electric voltage is applied to the scalp, and which has also been shown to boost learning.
Right now Krakauer is studying ways to use brain-imaging techniques to be able to spot those patients who can most benefit from this novel, intensive therapy. “These patients usually recover the least amount of function,” he says, “but with a robot and stimulation, we should be able to get improvement that goes far beyond what we usually see.”
- Challenge: Improve recovery of function lost to strokes
- Approach: Enlist video games, robots and brain stimulation to intensively train patients
- Progress: Animal data suggests the approach works; imaging studies on patients are under way