Researchers are working towards a prosthetic hand that could "convey real-time sensory information to amputees via a direct interface with the brain."
A research team has gotten one step closer to a "smart" prosthetic limb, a University of Chicago Medical Center news release reported.
"To restore sensory motor function of an arm, you not only have to replace the motor signals that the brain sends to the arm to move it around, but you also have to replace the sensory signals that the arm sends back to the brain," the study's senior author, Sliman Bensmaia, PhD, assistant professor in the Department of Organismal Biology and Anatomy at the University of Chicago, said. "We think the key is to invoke what we know about how the brain of the intact organism processes sensory information, and then try to reproduce these patterns of neural activity through stimulation of the brain."
The team has been working with Defense Advanced Research Projects Agency (DARPA) funds to create this revolutionary artificial limb that would restore both dexterity and sensation to amputees.
The researchers worked with monkeys (which have a sensory system similar to humans) and pinpointed regions of the brain that showed activity when perceiving the sense of touch. The team hopes to replicate these neural patterns artificially.
The monkeys were taught to recognize certain patterns of physical contact on their hands. The team then attached electrodes to the monkeys' brains and created the same patterns using electrical stimuli delivered to the appropriate areas of the brain. The researchers found that the monkeys still recognized the signals even when they were created artificially.
The team also worked on the sensation of pressure. The team "developed an algorithm to generate the appropriate amount of electrical current to elicit a sensation of pressure." The monkey's were also able to successfully identify the sensations even when they were created artificially.
Bensmaia believes the technique is getting closer to being ready for clinical trials with humans.
"The algorithms to decipher motor signals have come quite a long way, where you can now control arms with seven degrees of freedom. It's very sophisticated. But I think there's a strong argument to be made that they will not be clinically viable until the sensory feedback is incorporated," Bensmaia said. "When it is, the functionality of these limbs will increase substantially.
