WASHINGTON (Dispatches)-Stroke patients who learned to use their minds to open and close a plastic brace fitted over their paralyzed hands gained some ability to control their own hands when they were not wearing the brace, according to a new study from Washington University School of Medicine in St. Louis.
By mentally controlling the device with the help of a brain-computer interface, participants trained the uninjured parts of their brains to take over functions previously performed by injured areas of the brain, the researchers said.
"We have shown that a brain-computer interface using the uninjured hemisphere can achieve meaningful recovery in chronic stroke patients," said Eric Leuthardt, MD, a professor of neurosurgery, of neuroscience, of biomedical engineering, and of mechanical engineering & applied science, and the study's co-senior author.
"We chose to evaluate the device in patients who had their first stroke six months or more in the past because not a lot of gains are happening by that point," said co-senior author Thy Huskey, MD, an associate professor of neurology at the School of Medicine and program director of the Stroke Rehabilitation Center of Excellence at The Rehabilitation Institute of St. Louis. "Some lose motivation. But we need to continue working on finding technology to help this neglected patient population."
The Ipsihand, a device developed by Washington University scientists, comprises a cap that contains electrodes to detect electrical signals in the brain, a computer that amplifies the signals, and a movable brace that fits over the paralyzed hand. The device detects the wearer's intention to open or close the paralyzed hand, and moves the hand in a pincer-like grip, with the second and third fingers bending to meet the thumb.
"Of course, there's a lot more to using your arms and hands than this, but being able to grasp and use your opposable thumb is very valuable," Huskey said. "Just because your arm isn't moving exactly as it was before, it's not worthless. We can still interact with the world with the weakened arm."