Bionic beings who are part-human, part-machine may sound like a concept that still belongs in science fiction stories. But experts say that cyborgs are already walking among us, and have been around for quite some time.
When one-eyed filmmaker Robert Spence wanted to sell a documentary film idea of becoming an "EyeBorg," he installed a cheap LED light in his prosthetic eye. The simple addition instantly made his cyborg concept recognizable to potential business partners as he closed in on a possible deal for his documentary.
"Cyborg is your grandma with a hearing aid, her replacement hip, and anyone who runs around with one of those Bluetooth in-ear headsets," said Kosta Grammatis, an engineer who worked with Spence on the EyeBorg project.
That illustrates the gulf between what experts and ordinary people think of when they imagine a cyborg (cybernetic organism). Many experts see a modern world filled with cyborgs, whether they wear exoskeleton robot suits and prosthetic limbs or pacemakers and eyeglasses. Yet the public still prefers the fictional Robocop and Terminator -- science fiction concepts that have not yet become fully realized in the real world. [5 Reasons to Fear Robots]
The stretchy definition of cyborg came up recently in an exhibit at the American Museum of Natural History in New York City, which listed both the villainous Darth Vader of Star Wars fame and the heroic Master Chief from the popular Halo video games as cyborgs.
Few would dispute that Darth Vader fits the cyborg definition. His transformation from troubled Jedi Anakin Skywalker into the dark lord of the Sith forces him to rely upon mechanical limbs and a life support system that gives his breathing its classic menacing edge.
But Master Chief, a genetically enhanced "Spartan" super-soldier who wears an armored power-suit, seems a more unlikely cyborg candidate, according to popular opinion. More than 76 percent of gamers on the website Giant Bomb do not consider Halo's Spartans to be cyborgs, according to an informal poll conducted by LiveScience.
"What a cyborg is, in big part, is a fictional character from the future," Spence said.
From human to cyborg
The futuristic aspect of cyborgs weighs heavily on the popular definition, as Spence quickly realized. His conceptual success with EyeBorg's cheap light comes despite the fact that the prosthetic acts as a separate camera and has no functional connection to his body.
"Nobody calls people with a prosthetic eye cyborgs, but put in a $5 LED light and you look like the Terminator," Spence pointed out.
The Terminator also makes the cyborg list in the American Museum of Natural History's new brain exhibit. But whereas Darth Vader and Master Chief (and Spence) began their lives as humans, the original Terminator is a killer robot coated with living human skin and flesh -- yet sci-fi fans regularly refer to it as a cyborg.
Popular depictions of cyborgs seem to fall all over the spectrum between human and machine. If Master Chief wearing a power-suit is at one end, then Darth Vader sits somewhere in the middle and the Terminator is at the machine end.
Then what about Luke Skywalker, the son of Darth Vader who loses his hand during a lightsaber duel?
"You see Luke Skywalker in a famous ending [of "The Empire Strikes Back"] opening, closing and flexing his hand," Spence said. "That's a classic cyborg moment – he's wondering if he's a cyborg."
To add to the confusion, the museum's cyborg lineup is rounded out by the Maria "machine-man" from the classic sci-fi film "Metropolis" and the computer HAL from "2001: A Space Odyssey."
HAL's inclusion in particular pushes the definition of a cyborg to an extreme, and raises the question of whether or not an artificial intelligence that gains self-awareness represents some mix between man and machine without any organic parts.
"As far as we are aware, HAL has a machine/computer brain, which pushes us into philosophical questions about whether it can ever completely exhibit human consciousness," said Kevin Warwick, a professor of cybernetics at the University of Reading in England.
A computer that had a brain made from biological neurons would perhaps represent a more likely cyborg, Warwick suggested.
"The 'best' definition I have seen of a Cyborg is a human enhanced well above the norm by technology which is integral to the body – particularly integral to the nervous system/brain," Warwick told LiveScience in an e-mail. "I feel that this is the sort of cyborg depicted/required by science fiction."
That approach fits with Warwick's own self-experimentation as "Captain Cyborg." In 2002, he had a neural interface chip implanted in his arm so that it could directly interpret signals from his nervous system. He later demonstrated the ability to directly control a robot arm and receive feedback from fingertip sensors, and even experimented with a form of electronic telepathy with his wife (who also had an implanted chip).
We are all cyborgs
Still, Warwick said that some definitions would allow any human using any piece of technology -- whether it's glasses, bicycles or pens – to count as a cyborg. Many other experts agreed with the most basic technical definition of a cyborg as a being that combines technology with human biology.
Humans are and always have been cyborgs, according to George Landow, a digital media scholar at Brown University. He pointed to "the most powerful of all technologies" in the form of language, and also included information technologies such as writing and math.
"Certainly, anyone who uses clothing or an umbrella is a cyborg," Landow said. "Anyone who uses medication, contact lenses, is well into cyborgism, and people like myself who have metal stents in their hearts and artificial lenses inside their eyes (after cataract operations), is definitely a cyborg according to the most conservative, cautious definition."
Todd Winkler, a professor of music at Brown, has even suggested that a pianist is a cyborg. The human musician knows how to play the piano without the instrument, but isn't really a pianist until he or she sits down at the piano.
Where we go from here
Something as mundane as a piano or clothing may indeed count as a cyborg component, but people view such things as commonplace, Spence explained. He suggested that technologies which already serve humans today may never quite satisfy the hankering for a really futuristic cyborg concept.
That implies the popular definition of a cyborg may simply be doomed to forever drift just out of our reach – never in the now, but always somewhere just beyond the future horizon.
"A cyborg is a human being who is augmented by technology," Spence said. "I'd say it's the most useful, super-technical definition, but it's the least fun. A lot of the point of defining a cyborg is to have fun."
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