The Next Generation of Prosthetics
Last year saw a groundbreaking innovation when Second Sight Medical Products's Argus II, the world's first bionic eye, was approved by FDA. Consisting of a retinal implant and external hardware, the Argus II treats patients with retinitis pigmentosa—giving blind patients a form of vision that Second Sight likens to a pixelated black-and-white TV. While we're still a long way away from the bionic technologies seen in science fiction films, researchers are making advancements toward improving and enhancing prosthetics that should make for some exciting developments in the coming year and beyond.
|Second Sight's Argus II retinal prosthesis was approved by FDA in 2013. |
Researchers worldwide have invested a lot in studying and developing brain-computer interfaces that will allow people with disabilities to control artificial limbs with their thoughts. In 2012, the team behind the BrainGate neural interface made waves by publishinging research detailing how a quadriplegic person was able to control a robotic arm with her thoughts using an iteration of the device.
Then, in November 2013, researchers at Duke University achieved another milestone, which they detailed in a study released in the journal Science Translational Medicine. Whereas the BrainGate team used a brain-machine interface to enable a patient to control a single robotic arm, the Duke researchers, led by Miguel Nicolelis, professor and codirector of the Duke University Center for Neuroengineering, developed an algorithm that allows rhesus monkeys to control two virtual arms. The study gave researchers new insights into how the brain processes bimanual tasks that could someday lead to patients being able to control two prosthetic arms with their thoughts.
"When we looked at the properties of individual neurons, or of whole populations of cortical cells, we noticed that simply summing up the neuronal activity correlated to movements of the right and left arms did not allow us to predict what the same individual neurons or neuronal populations would do when both arms were engaged together in a bimanual task," Nicolelis said in a statement. "This finding points to an emergent brain property—a nonlinear summation—for when both hands are engaged at once."
Nicolelis is incorporating the study's findings into the Walk Again Project, an international collaboration working to build a brain-controlled exoskeleton for paralytics. The Walk Again Project plans to demonstrate its first brain-controlled exoskeleton during the opening ceremony of the 2014 FIFA World Cup in June.
But BrainGate and the algorithm developed at Duke are invasive technologies, requiring electrodes to be implanted directly into a patient's brain. In another leap forward, Bin He, a biomedical engineering professor at the University of Minnesota’s College of Science and Engineering, has found a way to decode brainwave signals noninvasively, from a typical ECG cap used in neurological research. He's research has enabled individuals to remotely control a flying robot with their thoughts.
|The Walk Again Project aims to debut a working exoskeleton for paralytics at the 2014 World Cup.|
Researchers are also working to improve the overall quality of prosthetics. Researchers at the Cleveland Veterans Affairs Medical Center and Case Western Reserve University have developed a new interface that allows patients to feel a sensation of touch through a prosthetic hand. The interface uses 20 sensors to stimulate bundles of nerves in the hand, allowing for a tactile sensation and feedback that could give patients who have lost their hands more precision and control over their prosthetics.
Companies that manufacture bionic medical devices have had a a lot of difficulty when it comes to raising funding, particularly through venture capital. Venture capitalists often do not have the patience for the long-term investment required for innovative prosthetics (the Argus II was in development for more than 10 years) and opt instead to fund technologies that offer a faster return on investment. However, there are rumors of venture capital firms forming dedicated funds aimed at bionics. That, along with a government push in the United States, thanks to President Obama's Brain Research through Advancing Innovative Neurotechnologies (BRAIN) initiative through the National Institutes of Health, could spur more research and funding for companies looking create better bionic devices.