Robotic Arm Delivers Sense of Touch Straight to the Brain
Tapping the sensory cortex is the route to rediscovering feeling.
A new study has allowed a paralyzed man to feel the sense of touch once more by injecting electrical signals from a robotic arm into the sensory cortex of his brain.
Using implants within the brain to detect signals and move a prosthetic isn’t anything new. Nor is the idea of re-creating feeling using electrical signals. But this study differs from others because it taps into the sensory cortex—the part of the brain responsible for sensation—to stimulate a sense of feeling directly within the brain.
The patient involved in the study, Nathan Copeland, is unable to move his hands or legs after breaking his neck. He had a total of four electrodes implanted in his brain, according to the Verge. Two are situated in the motor cortex, allowing him to move a robotic arm, and the other two in the sensory cortex.
In training sessions over the course of six months, those electrodes were connected to sensors in a robotic hand that would supply electrical signals when they detected pressure. Copeland felt nothing at first, because the electrical signals were kept intentionally small. But over time they were increased, and he began to sense something. “It felt like I was getting my fingers touched or pushed,” he says in a video made by the University of Pittsburgh Medical Center.
Re-creating sensation for people with prosthetics isn’t frivolous. Touch provides the feedback that’s required for us to perform delicate tasks, such as hanging out the wash or folding a piece of paper. Without it, even everyday chores can be difficult.
Writing about the results in Science Translational Medicine, the researchers explain that the approach “could be used to convey information about contact location and pressure necessary for prosthetic hands to interact with objects.” There’s still some way to go before the approach is used widely, though: the robotic arm isn’t attached to Copeland yet, and the whole setup requires large quantities of hardware. But it does suggest that prosthetics could, at some point, provide a more realistic experience for their users.
(Read more: Science Translational Medicine, The Verge, “First Cyborg Olympics Will Celebrate How Technology Can Help Disabled People,” “Paralyzed Man’s Arm Wired to Receive Brain Signals,” “An Artificial Hand with Real Feeling”)
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