Monkeys use mind control to move a virtual arm and experience touch

The aim is to create a mind-controlled 'exoskeleton' that can restore movement and sensation to paralysed people

A brain implant allowed monkeys not only to move a virtual arm but also to experience tactile sensations. Photograph: Katie Zhuang

A brain implant that allows monkeys to move an avatar's arm and feel objects in a virtual world has been demonstrated for the first time.

The animals used the device to control the arm by thought alone, and feel the texture of the objects it touched through electrical signals sent directly to their brains.

Researchers built the system as part of a major effort to help paralysed people regain the use of their arms and legs, feeling the objects they touch and the ground they walk on.

Without any sensation of touch, it would be easy for people to crush or drop objects they were trying to grasp, or misjudge the terrain underfoot and stumble, the scientists said.

Miguel Nicolelis, who led the research team at Duke University in North Carolina, said the technology was a milestone in his group's bid to restore natural movement and fine control to paralysed people.

Nicolelis is working with colleagues at the Technical University in Munich to build a whole-body "exoskeleton" that can move people's paralysed limbs in response to brain activity picked up by the implant.

"The patient will be able to use their brain to control their movement, but they could also get sensations back from their legs, arms and hands," Nicolelis told the Guardian.

"We are looking to have a demonstration of this in time for the World Cup in 2014. When the Brazilian team walks on to the field, we want them accompanied by two quadriplegic teenagers who will walk on to the pitch and kick the ball using this technology."

Nicolelis, who was born in São Paulo, the largest city in Brazil, said the challenge was "like the Brazilian moonshot".

While a prototype exoskeleton might be more conspicuous than most patients would like, it will be quiet and made of lightweight materials. "Even the first generation is not going to be like Robocop," Nicolelis said.

Writing in the journal Nature, Nicolelis describes a series of experiments in which monkeys learned to perform tasks on a computer in exchange for a reward, in this case a sip of fruit juice.

In the first round of experiments, the monkeys used a joystick to move a virtual arm on the computer screen in front of them. The screen displayed three identical images, each a circle within a circle. As the virtual hand moved over each, the joystick vibrated to convey one of three different "textures". Using trial and error, the monkeys worked out that they received some juice when they placed their virtual hand in the centre of a circle with a certain texture.

In the second round of experiments, the monkeys switched over to the brain implant. This time, they moved the virtual arm by thoughts, which were picked up by fine wires inserted into the motor cortex region of their brains. The electrical activity of between 50 and 200 brain cells controlled the arm's movements.

When the monkeys moved the virtual arm onto a circle, they experienced a sensation of texture from tiny electrical pulses sent directly to thousands of neurons in part of the brain called the primary tactile cortex.

The more time the monkeys spent with the implant, the more they appeared to view the virtual arm as a natural part of their body. "They got better and better at the task over time. By measuring how long they spent on each circle, you could see they were really focused on finding the right texture," Nicolelis said.

Nicolelis calls the device a brain-machine-brain interface, because it translates brain activity into movement while sending information on texture back into the brain.

"The remarkable success with nonhuman primates is what makes us believe that humans could accomplish the same task much more easily in the near future," Nicolelis said. "We hope that in the next few years this technology could help to restore a more autonomous life to many patients who are currently locked in without being able to move or experience any tactile sensation of the surrounding world."

Courtesy : http://www.guardian.co.uk

SCIENTISTS TO REVEAL GOD PARTICLE FINDINGS

By Genevieve Gannon, AAP

An experiment accused of jeopardising the future of the planet will reach its climax this week.

Scientists will on Wednesday reveal the findings of their investigation into the piece of sub-atomic matter dubbed the God particle.

There are three possible outcomes to the 30-year search for the Higgs boson, a theoretical particle that is key to the scientific understanding of all matter.

The first outcome - they will prove its existence.

The rule book for how particles have mass operates under the assumption the Higgs boson exists.

The Higgs boson theory is a missing piece of the rule book, which would have to be rewritten or scrapped if scientists discover the particle doesn't exist.

The second outcome - they will find something previously unthought of.

The third outcome - they will be able to rule out the existence of the Higgs Boson altogether.

Melbourne University physicist Geoff Taylor, who has been involved in the Geneva project since 1989, says the significance of the experiment cannot be overstated.

"The existence or not of the Higgs is an absolutely pivotal moment," Prof Taylor said.

"For us it's an incredibly important step in understanding the universe around us."

Should the Higgs boson be discovered, scientists will be able to explore other mysterious phenomena such as dark matter.

Last week, physicists started analysing the data collected from the latest batch of experiments in Geneva.

Even they don't know what they will find.

"We know we have to discover something in this energy range," Prof Taylor said.

"The simplest thing would be the Standard Model Higgs."

The experiments having been taking place below the Geneva airport and surrounding farmland.

The Large Hadron Collider, which is housed in a 27 kilometre long tunnel, has been "smashing" particles together.

Data has then been collected from the sub-atomic fragments released by the collision.

Scientists have been analysing the data in a double-blind test, to minimise the interference of what Prof Taylor calls human foibles.

"We have to find one particular event in about a million million events," Prof Taylor says.

The experiment has previously met with opposition.

There were some who believed it could cause the end of the world because the smashing of the particles would result in the generation of mini black holes.

Prof Taylor dismissed the claims.

"As soon as you say there is the possibility of creating black holes you have people saying we are going to be swallowed up by black holes," Prof Taylor said in 2008.

"It's completely misguided."

An announcement will be made in Geneva and Melbourne at 6pm (AEST) on Wednesday.

"Whatever comes out comes out, we don't know what that will be yet," Prof Taylor said.