A woman paralyzed from the neck down was able to move a robotic hand using her thoughts almost as freely and naturally as people without disability, aided by tiny electronic implants in her brain, scientists said.
The 52-year-old patient, diagnosed 13 years earlier with a rare degenerative disease that wears away brain and spinal structures, moved the prosthesis by the second day of training, researchers said today in the Lancet medical journal. Scientists at the University of Pittsburgh conducted the study.
Two microelectronic devices were implanted into the left motor cortex of the woman’s brain and connected to a detached robotic hand. The procedure allowed her to perform activities -- such as pouring water from one glass to another -- with a level of coordination and skill close to that of an able-bodied person, said Andrew Schwartz, the lead researcher. The results build on earlier, similar efforts to create devices that transform neural activity into control signals to robotic limbs.
“These are very natural movements instead of simplified machine movements,” said Schwartz, professor of neurobiology at the University of Pittsburgh, in a phone interview. “We have a much, much higher level of control than we had before.”
The medical advance was achieved through development of an algorithm that draws on 25 years of basic scientific research into how the brain works when we move our arms and wrists, Schwartz said. That has allowed his team to retrieve much more detailed information from the brain compared with earlier research, he said.
Researchers at Brown University’s Institute for Brain Science published a study in the journal Nature in May, describing two people paralyzed by strokes who were able to control robot arms using their thoughts. The procedure enabled the patients to grasp objects made of foam.
While this field of neuroprosthetics may soon become a “revolutionary” treatment model for paralysis, several challenges lie ahead, Gregoire Courtine of the Swiss Federal Institute of Technology wrote in a comment accompanying the article.
The study was conducted in a controlled environment of laboratories where highly skilled engineers can fine tune the technology daily, Courtine said. Technical issues such as making the system wireless and operational for decades without daily tweaking remain, he said.
Next steps include adding sensory elements so that the patient may be able to distinguish between hot and cold, and smooth and coarse surfaces, the authors said.
Research on prosthetic hands and arms also serves as a gateway toward ultimately helping patients move their own limbs through electrical pulses, Schwartz said.
“But that is much more difficult to do,” he said. “As an intermediary step, we’re having the subjects use a prosthetic arm.”
To contact the reporter on this story: Makiko Kitamura in London at email@example.com