Krishna Shenoy and team have been researching the use of brain machine interfaces (BMI) to assist people with paralysis. Recently, one of the researchers changed the task, requiring physical movement from a change in thought. He realized that the BMI would allow study of the mental rehearsal that occurs before the physical expression.
Although there are some important caveats, the results could point the way toward a deeper understanding of what mental rehearsal is and, the researchers believe, to a future where brain-machine interfaces, usually thought of as prosthetics for people with paralysis, are also tools for understanding the brain.
"Mental rehearsal is tantalizing, but difficult to study," said Saurabh Vyas, a graduate student in bioengineering and the paper's lead author. That's because there's no easy way to peer into a person's brain as he imagines himself racing to a win or practicing a performance. "This is where we thought brain-machine interfaces could be that lens, because they give you the ability to see what the brain is doing even when they're not actually moving," he said.
"We can't prove the connection beyond a shadow of a doubt," Krishna said, but "this is a major step in understanding what mental rehearsal may well be in all of us." The next steps, he and Vyas said, are to figure out how mental rehearsal relates to practice with a brain-machine interface – and how mental preparation, the key ingredient in transferring that practice to physical movements, relates to movement.
Meanwhile, Krishna said, the results demonstrate the potential of an entirely new tool for studying the mind. "It's like building a new tool and using it for something," he said. "We used a brain-machine interface to probe and advance basic science, and that's just super exciting."
Additional Stanford authors are Nir Even-Chen, a graduate student in electrical engineering, Sergey Stavisky, a postdoctoral fellow in neurosurgery, Stephen Ryu, an adjunct professor of electrical engineering, and Paul Nuyujukian, an assistant professor of bioengineering and of neurosurgery and a member of Stanford Bio-X and the Stanford Neurosciences Institute.
Funding for the study came from the National Institutes of Health, the National Science Foundation, a Ric Weiland Stanford Graduate Fellowship, a Bio-X Bowes Fellowship, the ALS Association, the Defense Advanced Research Projects Agency, the Simons Foundation and the Howard Hughes Medical Institute.
Excerpted from Stanford News, "Mental rehearsal prepares our minds for real-world action, Stanford researchers find," February 16, 2018.
Brain-Sensing Tech Developed by Krishna Shenoy and Team, September 2016.
Krishna Shenoy receives Inaugural Professorship, February 2017.