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R_www.latimes.com_science 2015 00694.txt.txt

#Paralyzed man walks with help of robotic exoskeleton at UCLA"Good stuff!""Irish motivational speaker Mark Pollock says when he's agreeing to a proposal or signing off of a conversation. But for Pollock, who's been blind for 16 years and paralyzed from the waist down since 2010, "good stuff"doesn't even begin to capture the experience of being"Iron Electrirx Man"in a robotics lab at UCLA. In the early spring of 2014, Pollock became the first subject in a UCLA experiment that set out to meld electrical stimulation therapy with a robotic exoskeleton that effectively walks for paralyzed patients. The study's aim: to help those with spinal cord injuries learn to walk again. After a fall out of a second-story window caused Pollock's catastrophic spinal cord injury in 2010, physicians told him any return of sensation or function below his waist was out of the question. Pollock, who has been blind for 16 years, took the news with the same combination of acceptance and defiance that had led him to participate in endurance trials and adventure races across some of Earth's harshest terrain, including to the south Pole. He would learn to make a meaningful life using a wheelchair Pollock said in an interview. But he also resolved to"keep the paralyzed bits in good enough shape that I'd be ready for any innovation that came down the track, "he added. After nearly four years of aggressive rehabilitation efforts, Pollock arrived at UCLA having already mastered the use of a battery-powered wearable bionic suit, called an Ekso. The robotic exoskeleton's sensors and motors are programmed to detect how much"help"a patient is capable of giving, and then to do the rest of the stepping. Pollock's injury was broken so extensive bones had nicked and pierced his spinal cord in two places--that he was, essentially, a passenger in the exoskeleton. That, however, was about to change. In the lab of V. Reggie Edgerton, professor of integrative biology and physiology, neurobiology and neurosurgery, Pollock had attached electrical patches to the skin over his spinal cord. Over the course of a week, he got five hours of electrical stimulation--without so much as a pinprick. When Pollock strapped on the Ekso after that, "it felt like I was moving up to the'sport'version of the device, "he said. His heart rate increased. He felt perspiration burst from his brow. And he felt another sensation he had missed for four years: tension in his legs, which turned to tingling as his legs"joined in with the movement"of the Ekso, he said. He could walk up to his fiancee and hug her, said Pollock. He could engage others from an active, standing position. He felt the tension in his hips ease. His legs felt looser, and his digestion improved.""It felt, like, right,"said Pollock.""It felt like it used to feel.""Edgerton, who presented the case in Milan, Italy, this week to the world largest international society of biomedical engineers, said the electrical stimulation to the spinal cord appears to reawaken neurons there. Once abuzz, those spinal neurons appear to recognize sensations sent up by the moving lower limbs --and respond by ordering muscles to pitch in to aid the movement. Even if the brain is out of the loop, the spinal cord appears to retain some of the"automaticity"that allows people with full function to initiate and make movements with little to no conscious effort, says Edgerton.""After the injury there a lot of functional capability that remains,"Edgerton said.""But it has to do some relearning"--a process that appears to be started jump by electrical stimulation, he added. By providing a natural stepping movement to the legs, the Ekso appears to remind the spinal cord what walking"feels"like. And as the spinal cord responds by initiating muscle movement, the Ekso's sensors and motors adjust, and provide less stepping power. Challenged to do more, the reawakened spinal cord neurons may to a point, continue to relearn their old ways. Whether that process leads a paralyzed patient to walk again depends on the extent and location of his or her spinal cord injury said Edgerton.""If they practice and regain 50%of control, that highly significant,"said Edgerton, who called the latest effort a proof of principle. The lead author of the new research, published this week by the IEEE Engineering in Medicine and Biology Society, is UCLA research scientist Parag Gad. Lead coauthors were Yury Gerasimenko, director of the laboratory of movement physiology at Russia Pavlov Institute and a researcher in UCLA's department of integrative biology and physiology; and Dr. Daniel Lu, associate professor of neurosurgery at UCLA David Geffen School of medicine. In a study published by the same team this summer in the Journal of Neurotrauma, five paralyzed men were given one 45-minute training session per week for 18 weeks, and regained voluntary control of their legs.""We think the future in robotics and rehabilitation is that the device will assist but will not completely take over, so the person has to regain some voluntary movement and to assist the device in making voluntary movements, "said Edgerton.""The robot will do less and less and the subject will do more and more

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