July 11, 2015
It turns out the old expression "two heads are better than one" is scientifically valid, and three heads are better than two even if they belong to monkeys.
Duke University researcher Miguel Nicolelis, best known for creating the brain-controlled exoskeleton that allowed a paraplegic man to take the opening kick in the 2014 World Cup, released the results of a new brain-machine interface study that tested signal transmission on rodents and primates.
Nicolelis and his team, who use brain signals to directly control the movements of artificial devices, wanted to test a network of the monkeys' brain signals, called a 'brainet,' to see if a set of tasks would be better performed by an individual monkey or a combination of all three.
In one experiment, the monkeys, outfitted with implants, were given control over separate axes to guide an avatar toward a target. Another experiment recorded the electrical activity of more than 700 neurons across the three monkeys in their effort to move a virtual arm toward a target.
“Participating in the Brainet, all three monkeys were able to synchronize their brain activity to produce a unified output capable of moving the virtual arm in 3-D,” said Nicolelis, M.D., Ph. D., and co-director of the Center for Neuroengineering at the Duke University School of Medicine.
“This is the first demonstration of a shared brain-machine interface, a paradigm that has been translated successfully over the past decades from studies in animals all the way to clinical applications. We foresee that shared-BMIs will follow the same track and soon be translated to clinical practice.”
The experiments found that the three rhesus monkeys were more effective at performing the given challenges when they synchronized their collective work to produce a "supra-brain" that guided movements along all three axes, as opposed to working alone.
These findings could now help Nicolelis and Duke's Brazil-based Walk Again Project, which hopes to develop a non-invasive human brainet that will help severely paralyzed patients advance in neuro-rehabilitation.