Monkeys move virtual limbs using brainwaves

A new brain implant has allowed monkeys to move virtual arms and to feel physical sensations from objects inside a computer. It's a major step towards fully functioning artificial limbs.

Will humans one day be able to move objects around using the power of thought alone? It sounds like science fiction, but researchers at Duke University in the USA have taken an important step towards turning that vision into science fact.

In a newly published experiment, Dr Miguel Nicolelis and his team show that owl monkeys with special brain implants can successfully control virtual limbs on a computer. Even more exciting, these limbs can 'feel' the texture of objects within the virtual space, transmitting sensations back to the monkey pilots by stimulating their brain cells with electric currents.

This is a big step. Virtual limbs which can both send and receive information (like sensations, for example) could feel, to the user, almost as natural as the real thing.

And these mind-controlled limbs don't have to stay virtual. In another huge recent breakthrough, a man who was paralysed from the neck down managed to use brain implants to move a real robot arm. 'Tears were flowing,' he said, describing how he awkwardly reached out for the first time to take his girlfriend's hand.

Combining this sort of robot prosthetic with Dr Nicolelis' two-way implants could lead to a tipping point in bionic technology – a moment when the sophistication and power of both implants and artificial limbs radically increases. The doctor's next ambition is to get paralysed teenagers using his technology to drive full-scale robotic exoskeletons, which would allow them to walk, run, or even kick a football.

He hopes to be able to demonstrate such devices at the Football World Cup in three years time.

The immediate uses of bionic technology are medical – restoring movement to amputees or quadriplegic s. In the long term, however, things needn't necessarily end there. Nicolelis noted that driving a virtual limb didn't seem to interfere with the monkeys' use of their other limbs – instead, they incorporated the virtual limb as if it were a newly grown extra.

Cyborg future

This raises an interesting possibility. What if, in the far future, bionic limbs were not just replacements but upgrades? An extra robot arm might turn out to be pretty useful. What about mechanically reinforced legs that would allow us to run at 60 miles per hour or jump over buildings?

For some, this will be the stuff of fantasy. As one online commenter opined, replacing our 'weak flesh' with 'unstoppable cyborg robo-bodies' would be 'just awesome'. 'Can I get mine with missiles?' added another.

For others, this fantasy looks like a nightmare. The body is a temple, people sometimes say, and if so, brain implants and robot limbs must be sacrilege – an attack on human nature itself.

You Decide

  1. Is it wrong to mess with the human body without good reason?
  2. What the impact be on society if bionic 'upgrades' became a real possibility?


  1. Do some research into past visions of engineering the human body, fromTerminatororRobocopall the way back to Frankenstein's monster. How have these visions changed, and why?
  2. Human bodies are incredibly well constructed. Try designing an artificial limb that would be capable of the full range of movement you can get from a real one. It's far from easy.

Some People Say...

“This is the beginning of the next step in human evolution.”

What do you think?

Q & A

How exactly did the monkeys control the virtual limbs?
Muscle movement is controlled by an area of the brain called the motor cortex. Brain cells use electrical impulses to signal to muscles when they should relax or contract. By putting an electrode into a monkey's brain, it's possible to sense those electrical impulses.
What then?
The signals are beamed wirelessly to a computer where they are translated into movement of a virtual arm. Electrical impulses in a particular area of the brain translate into particular kinds of movement. Eventually, the monkeys learn which signals (in effect – which thoughts) do what and are able to control the virtual arms like ordinary limbs.

Word Watch

In the scientific world, experimental findings aren't taken seriously until they are published in a scientific journal, which only happens after they have been rigorously reviewed. Publication allows other scientists to examine and criticise other people's findings.
Imitating biological systems using machinery. The term was made popular by the 1970s TV show, Bionic Woman.
In nature, exoskeletons can be found in creatures like crabs or insects. The word means a skeleton that is on the outside of the body.
Quadriplegia is full paralysis below the neck. Paralysis of only the lower half of the body is called 'paraplegia'.

PDF Download

Please click on "Print view" at the top of the page to see a print friendly version of the article.