The brain-controlled electronic hand offers the most advanced artificial touch to date

Scientists are getting closer to something that wouldn’t seem out of place in science fiction movies: bionic limbs that can sense and transmit touch to their users.

In a new study published this week, researchers have debuted an electronic hand system that can reproduce the most complex touch sensations seen to date. Scientists at the Cortical Bionics research group have developed a new brain-computer interface (BCI) device, which has been tested by volunteers with spinal cord injuries.

Through a series of experiments, the researchers were able to translate and transmit sensations associated with movement, curvature and direction, allowing volunteers to perform complex tasks using their bionic limbs. The researchers say their devices have now achieved a new level of artificial touch.

There have been some Important progress In recent years, prosthetics and bionic limb technology are still a far cry from fully approximating the complex nature of human touch. Some scientists have begun to use intracortical microstimulation (ICMS) of the brain’s somatosensory cortex to fill this gap, as experiments have shown that such stimulation can produce vivid tactile sensations on people’s skin. According to study researcher Giacomo Valli, early attempts using ICMS focused largely on reproducing sensation location and intensity. But there’s a lot more to feeling something than just those two aspects.

“While contact location and force are important components of feedback, the sense of touch is much richer than that, as it also conveys information about texture, material properties, local contours, and about the movement of objects across the skin. Without these rich sensations, artificial touch would remain poor.” And in their new study, published Thursday in sciencesVale and his team believe they have taken a decisive step forward with ICMS.

The researchers recruited two people with spinal cord injuries for their experiments. The volunteers were initially given brain implants in the sensory and motor areas of the brain that control the hands and arms. Through these implants, the researchers recorded and then decoded the different patterns of electrical activity produced by the volunteers’ brains as they contemplated using their paralyzed limbs. The volunteers were then connected to a BCI device that served as a bionic limb. Through their thoughts alone, the volunteers were able to control the limb equipped with sensors that communicate with implants in the brain. The researchers were then able to translate and send more complex touch sensations through the bionic limb to the volunteers’ brain implants.

“In this work, for the first time, the research went beyond anything done before in the field of brain-computer interfaces – we transmitted tactile sensations related to direction, curvature, motion, and 3D shapes to a participant using a brain-based device,” said Vali, a researcher in the field. Electronics at Chalmers University of Technology: “Our electronic limbs are controlled.” “We have found a way to write these ‘tactile messages’ via micro-stimulation using tiny electrodes in the brain, and we have found a unique way to encode them.” Complex sensations. This allowed for sensory feedback and a more vivid experience while using the bionic hand.

The volunteers could not only feel multi-layered sensations, such as touching the edge of an object—These sensations felt as if they came from their hands. The added input also appears to make it easier for volunteers to perform complex tasks with the bionic limb more accurately, such as moving an object from one place to another. This richness “is critical to achieving the level of dexterity, manipulation and high-dimensional tactile experience typical of the human hand,” Vale said.

The researchers point out that this is still early days. More sophisticated sensors and robotic technology, such as artificial skin, will be needed to capture the sensations that researchers can now encode and transmit to the user, Valley says, and more advanced brain implants will also be needed to increase the range of sensations that researchers can now encode and transmit to the user. user. can be stimulated. But Vale and his team hope that such progress can be achieved, and that a truly human-feeling bionic limb is within the realm of possibility.

“Although there are many challenges, this latest study provides evidence that the path to restoring touch is becoming clearer. With each new set of findings, we move closer to a future in which a prosthetic body part is not just a functional tool, but a way to experience the world.” .

The immediate next phase of Vale and his team’s research will be to test their BCI systems in more natural settings, such as patients’ homes. Their ultimate goal is to improve the independence and quality of life of people with disabilities.