According to researchers, Ian Burkhart, whose hands and legs were paralyzed in a diving accident in 2010, has regained the sense of touch,, through a brain implant, as opposed to simply the ability to move a hand:
The breakthrough came from analysis of years of data collected from NeuroLifeTM program study participant Ian Burkhart, who suffered a spinal cord injury in 2010 when diving into the ocean, and now lives with paralysis in his hands and legs. “When the chip was placed on the surface of Ian’s motor cortex in 2014, it was not known that the signals related to object touch could be observed because of the paralysis,” said lead author and Battelle Principal Research Scientist Patrick Ganzer. “Furthermore, Ian has a very severe SCI that should essentially block hand touch signals from even reaching the brain.”
However, analysis has shown that subperceptual touch following a spinal cord injury affects Burkhart’s motor cortex even though there is essentially a block from the nerves in his arms and their connection back to the brain. Importantly, this subperceptual signal can be detected in the brain, rerouted via the brain-computer interface and sent back to a wearable haptic system to restore the sense of touch.Newsroom, “Study Shows Sense of Touch Can Be Returned to Those with Spinal Cord Injury ” at Batelle
The medical paper at Cell is open access.
Paralysis can rob a person not only of the ability to move a limb but the ability to sense any signals from it. For nearly a decade, Mr. Burkhart has co-operated with pioneering research at Ohio State University’s Wexner Medical Center and non-profit research center Batelle. He made the science news in 2014 when it was reported that he could move his fingers and hand with his own thoughts, via a brain implant. In the same year, an implant enabled another man paralyzed from the waist down to gain control of a leg, so as to physically move it, via a landmark procedure at Kentucky Spinal Cord Injury Research Center.
In 2016, Burkhart regained the ability to move individual fingers, though it required him to master “controlling his thoughts” to avoid interrupting the brain-computer interface:
The neural bypass works using a microelectrode array implanted in Burkhart’s brain. The implant picks up activity in a specific area of his left motor cortex, which researchers had analyzed prior to placing the implant. Using functional magnetic resonance imaging (fMRI), which tracks brain activity based on blood flow, the researchers pinpointed the hand-controlling area of Burkhart’s brain while he repeatedly thought about moving his hand.
In the clinic, the implanted electrode hooks into a custom-built “neural bypass system.” The system picks up the signals from Burkhart’s brain activity, then, using machine learning algorithms, translates those signals to control a flexible arm sleeve, outfitted with 130 muscle-stimulating electrodes.
To get it to work, Burkhart attended three weekly sessions for 15 months. He mastered controlling his thoughts and could pull off six hand and wrist movements, including the ability to move individual fingers.Beth Mole, “Using synthetic nervous system, paralyzed man is first to move again” at ArsTechnica
But all that was movement, not sense of touch. As Victor Tangerman explains at Futurism, “A port in the back of his skull sends signals to a computer. Special software decodes the signals and splits them between signals corresponding to motion and touch respectively. Both of these signals are then sent out to a sleeve of electrodes around Burkhart’s forearm.” Burkhart told media, “It has been amazing to see the possibilities of sensory information coming from a device that was originally created to only allow me to control my hand in a one-way direction.”
The long-term goal, of course, is to enable the system to work as well at home as in the laboratory (ArsTechnica).
Meanwhile, Case Western Reserve University’s Department of Biomedical Engineering reported in 2017 that Bill Kochevar of Cleveland, quadriplegic due to a bicycle accident, had regained some movement after eight due to two temporarily implanted devices. However, he required nearly a year of rehabilitation for atrophied muscles before he could really benefit from the new technology:
To prepare him to use his arm again, Kochevar first learned how to use his brain signals to move a virtual-reality arm on a computer screen.
“He was able to do it within a few minutes,” Kirsch said. “The code was still in his brain.””
“When asked to describe how he commanded the arm movements, Kochevar told investigators, “I’m making it move without having to really concentrate hard at it…I just think ‘out’…and it goes.”Case Western Reserve University, “Man with quadriplegia employs injury bridging technologies to move again — just by thinking” at ScienceDaily
The medical paper was published at The Lancet.
Curiously, we still know nothing of the essence of the “thought” that makes us want to move a hand or a foot in the first place. That’s perhaps part of the enduring mystery (and hard problem) of consciousness.
Further reading on the way advanced electronics can help amputees, paralyzed people, and blind people recover some abilities:
Prosthetic hand controlled by thoughts alone? It’s here. Decades ago, no one could control a prosthesis only by thought. There is lots of room for the field to grow still.
High tech can help the blind see and amputees feel. It’s not a miracle; the human nervous system can work with electronic information.
New mind-controlled robot arm needs no brain implant. The thought-controlled device could help people with movement disorders control devices without the costs and risks of surgery.