The brain-controlled bionic hand offers the most advanced artificial touch ever

Scientists are approaching something that wouldn’t look out of place in a science fiction movie: bionic limbs that can sense touch and communicate it to their users.

In a new study published this week, researchers have debuted a bionic hand system capable of replicating the most sophisticated tactile sensations seen to date. Scientists from the Cortical Bionics Research Group have developed a new brain-computer interface (BCI) device that has been tested on volunteers with spinal cord injuries.

In a series of experiments, researchers were able to translate and transmit sensations related to movement, curvature, and orientation, allowing volunteers to perform complex tasks with their bionic limbs. The researchers say their device has now achieved a new level of artificial touch.

Some have been important developments in prosthetic and bionic limb technology in recent years, but these limbs are currently still far 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 overcome this gap, as experiments have shown that such stimulation can produce vivid tactile sensations on the skin of humans. According to researcher Giacomo Valle, early attempts with ICMS focused mainly on restoring sensation location and intensity. But there is much more to feel than these two aspects.

“While contact location and force are critical feedback components, the sense of touch is richer than that, also conveying information about texture, material properties, local contours, and the movement of objects on the skin. Without these rich senses, artificial touch would be very impoverished,” Valle told Gizmodo. In their new research, has been published Thursday in ScienceValle and his team believe they have taken an even more important step with ICMS.

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

“In this study, for the first time, the research went beyond anything previously seen in the field of brain-computer interfaces – we delivered tactile sensations of orientation, curvature, movement and 3D shapes to a participant using the brain. a controlled bionic limb,” said Valle, a bionics researcher at Chalmers University of Technology. “We found a way to record these ‘touch messages’ through microstimulation using tiny electrodes in the brain, and found a unique way to encode complex sensations. This allowed for a more vivid sensory feedback and experience when using the bionic hand.

The volunteers were not only able to experience the more layered sensations of touching the edge of the object—these feelings seemed to come from their own hands. The added input also appeared to make it easier for the volunteers to more accurately perform complex tasks with the bionic limb, such as moving an object from one place to another. And that richness, Valle said, “is critical to achieving the level of dexterity, manipulation, and high-dimensional tactile experience inherent in the human hand.”

Researchers note that these are still early days. Valle says that to actually capture the sensations researchers can now encode and transmit to the user, more sophisticated sensors and robotic technology, such as prosthetic skin, will be needed, and more advanced brain implants will be needed to augment the range of sensations. can be stimulated. But Valle and his team hope that such advances can be made and that bionic limbs that feel truly human are within reach.

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

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