Simian brain guides robotic arm

Scientists in America have used the brain signals from a monkey to drive a robotic arm in a laboratory over 600 miles away.

As the animal stuck out its hand to pick up some food off a tray, an artificial neural system linked into the animal’s head mimicked the activity in the mechanical limb.

‘The idea of driving robotic limbs with what effectively amounts to the mere power of thought was once in the realm of science fiction,’ commented Sandro Mussa-Ivaldi, of the Northwestern University Medical School, and the Rehabilitation Institute of Chicago. ‘But this goal is edging closer to reality.’

Miguel Nicolelis, of Duke University and colleagues implanted an array of electrodes into areas of a monkey’s brain known to control motor function.

The electrodes were used to record brain activity as the animal learned reaching tasks, including reaching for four small pieces of food placed randomly on a tray.

Every time the monkey then moved its hand to grab the food, the computer was able to process the brain signals to make similar, real-time, three-dimensional movements in a robotic arm. The signals were even sent over a standard internet connection to control another arm in the Massachusetts Institute of Technology’s ‘Touch Lab’.

In previous research, it has been shown that a rat wired into an artificial neural system can make a robotic water feeder move just by willing it.

But the latest work sets new benchmarks because it shows how to process more neural information at a faster speed to produce more sophisticated robotic movements. That the system can be made to work using a primate is also an important proof of principle.

‘We have designed a new paradigm to study how the brain processes information,’ said Touch Lab director and co-researcher Mandayam Srinivasan.

‘Until fairly recently, we tried to understand the brain by looking at one neuron at a time, but we all know the brain works in a parallel mode requiring the activation of huge numbers of cells to produce any behaviour.

‘So the implementation of this technique for recording up to a 100 neurons in primates is a big deal for science.’