The Defense Advanced Research Projects Agency (DARPA) recently announced that a 28-year-old paralysed man has been able to feel sensations in his brain through a prosthetic hand.
The man, who has been paralysed for over a decade as a result of a spinal cord injury, was able to tell which of his mechanical fingers is being gently touched.
DARPA says that sophisticated neural technologies developed under its Revolutionizing Prosthetics project will enable people living with paralyzed or missing limbs to “not only be able to manipulate objects by sending signals from their brain to robotic devices, but also be able to sense precisely what those devices are touching”.
Kevin Lamarque / Reuters
How did DARPA achieve this feat?
They placed electrode arrays onto the sensory and motor cortex regions of the paralysed man’s brain. The sensory cortex region is responsible for identifying sensations, while the motor cortex directs body movements.
Johns Hopkins University developed the mechanical hand to which wires were connected helping the man control its movements with his thoughts. Sophisticated torque sensors on the hand can detect when pressure is being applied to any of its fingers, and can convert those physical “sensations” into electrical signals. The team used wires to route those signals to the arrays on the volunteer’s brain.
DARPA says that the man, who was blindfolded before the test was carried out, was able to report which of his fingers was being touched with nearly 100 per cent accuracy.
DARPA program manager Justin Sanchez said:
“By wiring a sense of touch from a mechanical hand directly into the brain, this work shows the potential for seamless bio-technological restoration of near-natural function.”
Details about the work are being withheld pending peer review and acceptance for publication in a scientific journal.
Although an agency of the US Department of Defense and responsible for development of military technologies, DARPA also funds non-military projects. The innovation that helps prosthetics to be controlled with the mind has also been developed by a 19-year-old American who made it from a 3D printer. Easton LaChappelle not only made the mind-controlled arm in just $350, he also uploaded the entire design and the building process
on the website of his robotics start-up to be used by everyone for free.