With some help from DARPA, researchers at Southern Methodist University may soon establish a lightning-fast two-way fiber optic connection between the brain and prosthetic limbs. Working with $5.6 million in DARPA funding, the Neurophotonics Research Center has a singular goal: build a biocompatible fiber optic sensor scaled down to carry individual nerve signals to and from the brain.
The ultimate objective is nothing less than the "Skywalker hand," prosthetics that interface seamlessly with the brain like real limbs. DARPA (and others) have pursued such technology actively for years, but while strides have been made modern prosthetics are still a long way from even closely mimicking the feeling of a real limb.
Most "robotic" prosthetics simply connect to healthy tissue to trigger movement in the limb – for instance, connecting a prosthetic arm to healthy chest muscle that the user then clenches to manipulate the hand – which requires the user to learn a whole new way of operating his or her new limb. DARPA wants to change that by figuring out how to convert and carry nerve signals through synthetic channels.
To that end, fiber optics are ideal. Where metallic implants might be rejected or corroded by the body's natural processes, fiber optic technology can more easily be made compatible with living tissue. And optical technology can shrink signal channels down very small, so small that hundreds or even thousands of sensors could be embedded into a single fiber connecting brain and prosthetic.
That's not to say it will be easy. But SMU researchers and DARPA clearly think it's technology worth striving for. If they can figure out the right combination of optical nerve stimulation and nerve-sensing tech, they may just develop a two-way interface that not only lets the brain command the limb naturally, but also allows the limb to "feel" sensations like heat or pressure. It might also allow for a spinal cord patch that could help those with spinal traumas regain mobility.