Thanks to a brain implant, a quadriplegic has regained the sense of touch with his right hand. Sensations also aroused with a robotic arm controlled by his brain.
Ten years after an accident that left him paralyzed, an American regained the sensation of touch thanks to a robotic arm controlled by a brain implant. A scientific and technological prowess presented in the journal Science Translational Medicine.
Nathan Copeland, 28, is the first quadriplegic patient to benefit from this system, still being tested, developed by a research team at the University of Pittsburgh. The young man underwent surgery last spring to place 4 microelectrodes, smaller than a shirt button, in the brain regions responsible for the sensation of touch for each of his fingers and the palm of his right hand.
By directly stimulating these areas of the brain, electrical information no longer needs to pass through the spine to elicit touch. Electrical stimulation awakens the lost capacities of patients. “I can feel things with all my fingers, it’s a really weird feeling,” he says a month after the operation. Sometimes it’s an electric sensation and sometimes it’s a pressure. But most of the time I manage to define precisely what I feel ”.
Touch found more than 6 months
After several experiments, the young man even manages to differentiate between cold and hot objects. Just with his hand, he manages to describe in 93% of cases what he touches. And when he uses the robotic arm with his eyes closed, he can identify the finger stimulated more than 8 times out of 10. A feeling of touch restored for almost 6 months.
“The most important result of this study is that microstimulation of the sensory cortex can generate a natural sensation rather than tingling,” says Professor Andrew Schwartz of the Department of Neurology at the University of Pittsburgh School of Medicine. In addition, this stimulation is harmless, and the sensations aroused last several months ”.
Improve prostheses
In view of these results, the authors assure that electrical stimulation of the brain can restore a sense of touch in paralyzed people and possibly in amputees. A crucial new dimension for designers of brain-directed prostheses. In fact, when we move our arms, we take into account the environment around us and we adapt to the objects in hand. This is in particular, which allows us to gently close our fingers around a chip so as not to break it and to hold a glass firmly to prevent it from slipping.
“The ultimate goal of this work is to create a system that can move and feel like a natural arm does,” concludes study leader Dr. Robert Gaunt. We still have a long way to go, but it’s a very good start ”.
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