We have previously written about prosthetic legs that can adjust to different terrains and prosthetic hands that can be mind-controlled—but now, new developments have reached a novel level of efficiency for prosthetics and neural implants.
A study published in the journal Science writes about an implant-controlled robotic arm that can send tactile feedback to the user with a second implant. This means that the user will experience the sense of touch through this robotic arm, allowing for more situational awareness.
Typically, people have a good idea of the placement and position of their limbs. This is because of a little-known sense called proprioception, which tells us about which body parts are where. Our sense of touch then lets us know the degree of firmness with which we have grasped an object, even if we aren’t looking at it.
Early robotic arms required active visual perception for them to function and interact with their surroundings. However, without the sense of touch, visual judgments are only estimations and require a lot more attention from users rather than the ability to “feel” what they are doing.
Fortunately, scientists have since been able to map the regions of the brain that process information transferred by sensory nerve cells in the hands. This research involves two electrode arrays implanted into the section of the brain designed to process information coming from the skin. When the 32 electrodes activate, the brain experiences the sensation of something manipulating their palm and fingers.
The study in question only involves one participant: a man paralyzed from the neck down who had worked with a robotic arm for two years via the brain implants placed within the motor-control region of his brain. Even without the sense of touch, the man maneuvered the robotic arm proficiently. For this study, researchers administered tactile feedback tests that include grasping variously shaped objects, carrying them somewhere, then releasing them.
The test results demonstrate that having the sense of touch significantly improved performance. The participant was able to execute the series of tasks nine times without the touch system, but more than a dozen times when the system was activated. The most notable advantage came from the participant’s ability to firmly hold the object. The time between touching the object with the robotic arm and lifting it from the table fell by two-thirds once the sensory feedback feature was turned on.
Of course, even though the results are extremely promising, much more research must be done. This initial study only includes one participant, so more tests have to be conducted to gain a more thorough understanding of the technology and to fine-tune it so that it’s ready to be made available to regular consumers and people in need.
Study Source: Science