Monkey think, monkey do.

Posted on February 9, 2011

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Last month I interviewed an inspirational man, Niall Strawson, who despite being left with a spinal cord injury from a recent accident, is determined to continue working in the field and is planning his first trip back to Africa this summer.

Scientists all over the world continue to research ways of overcoming human paralysis. At Duke University in North Carolina, a Brazilian professor of neuroscience, Miguel Nicolelis and his colleagues are currently collecting data for a research paper, which has not yet been published.

Professor Nicolelis believes that by tapping brain signals and rerouting them through computers to artificial limbs , it could enable a paralysed person to move or even walk again.

Researchers at Duke University Medical Centre

Researchers have begun teaching monkeys to control with their thoughts, a full-body avatar projected on a computer screen. Directing the movements of an entire body is much more difficult than controlling just an arm or leg.

In an experiment, information was uploaded into a monkey’s brain via a wire and tiny electrode. It’s thought to be the first transmission of electronic data direct into a primate brain. They did this by opening up small holes in the skulls of the monkeys and then implanted each hole with a microchip fitted with 700 or so tiny hair-like electrodes.

These penetrated a few millimetres into the surface of the brain. Some of the electrodes were then used to record signals and some to pump in data from outside. The real test was to see whether the monkeys would learn to recognise what the signals meant.

monkey receives controls to the brain to allow movement

Professor Nicolelis who runs  the centre for neuro-engineering at the university says he and his team have had some success in trials but still have some way to go.

With paralysis, “the body you live in has changed. You need to remap how commands from the brain get to the rest of the body,” he says.

“When you walk, vision is not enough to control your body; you need sensory data about gait and speed, too.

“It means if paralysed people are to learn how to control these exoskeleton suits, the signals have to flow both ways, into the brain as well as out.”

If this type of technology is going work for those who are disabled, then Professor Nicolelis says the implants used, would need to be improved so that each carried not hundreds but thousands of micro-electrodes.

Currently the electrodes implanted in the monkeys are able to record up to about 1,000 neurons from above the cortex, the part of the brain that is involved in thinking and memory. This is enough to operate a full-body prosthetic. He and his team are working on technology that will allow them to record signals from 5,000 neurons, and eventually from 50,000.

Walk Again

Dr. Nicolelis says the research program has recently received a grant to begin testing on people a full-body prosthetic controlled solely by the patient’s brain waves. It’s expected to begin in 2014.

He added: “Based on our experiments with brain-machine interfaces in monkeys, I expect that after a few weeks of interaction, the patient’s brain will completely incorporate the entire exoskeleton as a true extension of the person’s body image. The patient will be able to use the brain-interface-controlled exoskeleton to move freely and autonomously around the world.”

Previous experiments carried out by researchers elsewhere in America have allowed monkeys to send signals to control movement.

In 2008, scientists at University of Washington in Seattle implanted ultra-thin electrodes into the brains of macaques (Macaca – these are old world monkeys and can be found in North Africa; Gibraltar and even in Japan)) trained to play a game that involved rotating their wrist to the left and right. While the monkeys played, the electrodes picked up electrical signals in their brains that made them tense different muscles. The monkeys were then injected with a chemical that temporarily paralysed their arms. This time, signals from nerves in their brains were fed into a computer, cleaned up and magnified, and sent down a wire to muscles in the monkeys’ wrists.

When the monkeys tried to play the game again, they were unable to at first, but soon learned to control their wrist movements using the brain implant.

This latest research by Dr Nicolelis and his team however concentrates on subjects receiving signals. This type of technology being developed is extraordinary and will give hope to so many. Scientists predict in time perhaps this could also could open the way for humans to control computers and machines by thought alone, and longer term perhaps even see us communicate with each other.

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Posted in: My brain hurts!