Eight people who had been left paralyzed below the waist as a result of spinal cord injuries have managed to regain some of the feeling and muscle control in their legs, after taking part in a year-long virtual reality training program. All patients had been paraplegic for between 3 and 13 years, yet after 12 months of training, all eight experienced improvements in somatic sensation, resulting in half of them having their diagnoses upgraded from complete to partial paralysis.
These incredible results were achieved thanks to a revolutionary new treatment program, devised by researchers from Duke University and carried out at the AASDAP Neurorehabilitation Laboratory in Sâo Paulo, and described in a paper published this week in the journal Scientific Reports. To begin with, patients learned to control a virtual reality avatar using only their brainwaves. According to study co-author Miguel Nicolelis, this “reinserted the representation of lower limbs into the patients’ brains.”
Once participants had mastered this exercise, they began a new phase of physical training, using harnesses and brainwave-controlled exoskeletons to provide balance and support while they attempted to move their legs.
Though the level of success varied from patient to patient, the researchers write that all eight “regained voluntary motor control in key muscles… resulting in marked improvement in their walking index.” They also experienced improvements in their ability to feel pain in their legs, as well as regaining a degree of bladder and bowel control. This is significant as it means they may become less reliant on laxatives and catheters, which are often the source of potentially life-threatening infections for paralyzed people.
WALK_AGAIN_PAPER_4_SD from Nicolelis Lab on Vimeo.
Among the biggest improvers was a woman who, while supported by a harness, was able to voluntarily move her legs for the first time in over a decade.
Though it is not yet clear exactly how this effect is achieved, Nicolelis believes that the training program enables patients to reconnect their brains to the few spinal nerves that survived the accidents that left them paralyzed in the first place. “One previous study has shown that a large percentage of patients who are diagnosed as having complete paraplegia may still have some spinal nerves left intact,” he explained in a statement.
“These nerves may go quiet for many years because there is no signal from the cortex to the muscles. Over time, training with the brain-machine interface could have rekindled these nerves. It may be a small number of fibers that remain, but this may be enough to convey signals from the motor cortical area of the brain to the spinal cord.”