Paraplegics who suffered spinal cord injuries spent a year training on brain-machine interfaces, and all of them experienced improvements in their recoveries.
Researchers witnessed something that has never been seen in the field of medicine – people who have been paralyzed for more than a decade have regained some sensation and neurological control in their key muscles, which means that they can move a bit again.
According to a small study published in the journal Scientific Reports, brain-machine interfaces used for this study are actually a virtual reality systems and robotic exoskeletons which allowed paraplegic people to use their own brain activity to stimulate control of their legs.
The results of this study suggest that long-term training on interfaces which utilize the virtual world could help paraplegics to regain sensations and possibly mobility in the real world, said Dr. Miguel Nicolelis, a neuroscientist at Duke University who led the study as part of the Walk Again Project in São Paulo, Brazil.
According to the World Health Organization, about 282,000 people are living with spinal cord injuries. Most of those injuries are the result of traffic accidents, falls or violence.
“Since I went to medical school, I heard that there was no hope to recover patients with spinal cord injury,” Nicolelis said.
“I was really shocked, so much that it took us several months to report this because we wanted to confirm every detail,” he said of the study findings. “Brain-machine interface, we designed this in the late ’90s as a potential technology to assist patients to move, as an assistive technology. We never thought that we would induce neurological recovery in these patients.”
Eight paraplegic patients, who had been completely paralyzed for at least three years, participated in this study. They had to spend at least two hours a week training on brain-machine interfaces over the course of a year.
How did the brain-machine work? Caps lined with electrodes were placed on patients’ heads; those caps recorded their brain activity. Brain activity triggered movements in virtual reality systems and robotic exoskeletons, such as making the virtual avatar of a patient walk. After that the interface sent signals back to the patient’s brain, such as sensation of a movement.
Cap lined with electrodes
“So you’re getting an exoskeleton, and your brain activity is triggering the device to move, and you’re getting feedback from the device. You’re feeling the ground; you’re feeling the legs walking,” Nicolelis said. “If the brain of a paralyzed person is engaged and imagining movements and controlling a device directly and then the brain gets feedback from this device and the body of the patient is moving too, the brain is reinforced. The brain says, ‘OK, I’m imagining that I’m moving, and something moved.’ ”
Clinical evaluations were conducted on each patient on the first day of the study and then repeated after four, seven, 10 and 12 months.
“After we did this for several months, we tested the patients outside of the brain-machine interface device, and to our shock, people who were not supposed to move ever again in their lives were spontaneously moving their legs and feeling sensations,” Nicolelis said.
All of the patients experienced significant improvements in their recoveries. Four of them improved so much that their diagnosis was changed from complete paralysis to partial paralysis.
Many of the patients reported improvements in their everyday lives. Some of them became more independent in the bathroom, they are able to more effectively move form their wheelchair to the toilet. Another patient reported an improvement in moving from his wheelchair to the car.
The researchers are also hoping that the brain-machine interface devices could be offered as a therapy for paraplegics all over the world.
Seven of the patients in the new study have continued their rehabilitation with brain-machine interfaces, and the researchers are continuing to document each patient’s progress.