Creepy Cyber-Monkeys Dwell in the Primate "Uncanny Valley"

By Brett Israel | October 14, 2009 4:47 pm

monkey_web2Humans typically feel uneasy when they see a very realistic human-looking robot or computer avatar, a phenomenon called the “uncanny valley” response. According to a new study performed with monkeys, that reaction might have an evolutionary basis.

Researchers hypothesize that the response stems from almost realistic images that signal HUMAN! to us, but then fail to live up to the initial excitement. The uncanny valley response has been documented in humans since the 1970s, and has been blamed for the unpopularity of some CGI films with realistic characters [like The Polar Express and Final Fantasy], and it is touted as the reason Pixar stuck to characters with cartoonish features [New Scientist].

uncanny-valleyThe response takes its name from a graph (pictured at left) of human emotional response as a function of a depiction’s human-likeness. As human-likeness increases, a positive emotional response also increases, until likeness reaches somewhere around 80 percent, then the emotional response shoots down to revulsion on par with viewing a human corpse.

Uncanny valley response has never been observed in another species. So to investigate the response’s evolutionary basis, researchers checked monkeys for the reaction. To test their preference, researchers showed macaque monkeys real pictures, digital caricatures and realistic reconstructions of other monkey faces. To the latter, the macaques repeatedly averted their eyes [], suggesting that monkeys also fall into the uncanny valley.

However the researchers couldn’t determine for certain whether the monkeys were repulsed by the almost real faces, or were simply more attracted or interested in the others. The best way to do that would be to repeat these experiments while looking for possible signs of unease–sweaty skin, dilated pupils or clenched facial muscles, as examples [Not Exactly Rocket Science]. The study was published recently in the Proceedings of the National Academy of Sciences.

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Images: PNAS / Asif Ghazanfar and Shawn Steckenfinger

CATEGORIZED UNDER: Living World, Mind & Brain, Technology
  • YouRang

    Independent of the existence of the uncanny valley, people didn’t watch Polar Express (and probably Final Fantasy which I didn’t see) because the characters over-emoted. Just consider all the cartoon stars; Porky Pig, Elmer Fudd, The Three Little Pigs–they’re all hams
    :-) . Of course, they are in fact less hams than most cartoon stars (since pigs are funny all by themselves). Just think about MM confronting the wizard after his debacle in THe Sorcerer’s Apprentice. Think about Daffy Duck sizzling after some failure. About the only non-hams are BB and RR. So in order to have a realistic cartoon character be appreciated, one must focus on the action. When Laurence Olivier first went from stage to screen, he was appalled at the way he looked on the screen; his reaction was What a Ham. And that’s from the greatest actor of his day. Stage actors can be hams because their whole body language is what is important. In too many scenes in Polar Express, the picture was a close up. And in close ups subtlety is important. Not many actors ever learn that. (IMO Meryl Streep is tremendously over-rated because she hasn’t learned Marlon Brando too, except in Don Juan de Marco (which I loved); I guess Johnny Depp was enough ham for one picture.)
    Comic Books are either action oriented (like Superman) or cartoonish (like Archie). In order for action figures to show emotion, they have to do it with body language rather than facial expressions.
    Bottom line: over-emoting is the norm in cartoons because there are always subtle clues in real life. Cartoonists don’t want to include the subtle clues since cartoons tend to be serials. Serials like Soap operas are in disrepute because the subtle clues frozen on an actor’s face are generally at odds with the story line eventually.

  • RoxyBlue

    You maybe onto something there, YouRang. I didn’t like the CGI Beowulf movie because the character’s faces lacked the emotional subtley of an actor’s face.

  • Gumba Masta

    “the emotional subtley of an actor’s face.”
    Is’nt that an oxymoron?

  • John Cassady

    Personally I liked Final Fantasy.

  • DrWoody007

    An interesting possibility to test the Uncanny Valley repsonse is to show different types of pictures to 6-12 month old infants. Why? Because babies are unbiased. How would you test babies who’s primary language is Babble? By measuring eye-aversion or better yet, pupil dialation, for each type of Unreal, CGI, and Real pictures. Be sure to use pictures of us ‘regular’ people and pictures of SuperModels. But, pictures of their siblings or especially parents will be the ultimate determining factor for this response.

  • Jon the action figure buff

    In my opinion studies of this nature can be flawed right from the start. When a man sees a picture of a woman (face or body) he finds genetically atractive, either a real woman or a CG, his pupils dilate. However when women see picture of attractive men they do not have much if any visual stimulation. Their pupils, however, dilate when they’re shown pictures of babies. These results show traces of primitive instinct inside each and every one of us: men think heavily in reproduction and spreading their seed with women they find to be a good genetic match; and women have the physical and emotional attachment to want to take care of their babies. This is the cornerstone of the preservation and continuation of our species (and others for that matter unless external influence was applied -like Man).


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