The term uncanny valley is a hypothesis in the field of human aesthetics which holds that when human features look and move almost, but not exactly, like natural human beings, it causes a response of revulsion among some human observers. The “valley” refers to the dip in a graph of the comfort level of humans as subjects move toward a healthy, natural human likeness described in a function of a subject’s aesthetic acceptability. Examples can be found in the fields of robotics and 3D computer generated images.
Wikipedia also states that “The term was coined by the robotics professor Masahiro Mori as Bukimi no Tani Genshō (不気味の谷現象) in 1970. The hypothesis has been linked to Ernst Jentsch‘s concept of the “uncanny” identified in a 1906 essay, “On the Psychology of the Uncanny”. Jentsch’s conception was elaborated by Sigmund Freud in a 1919 essay entitled “The Uncanny” (“Das Unheimliche“).
The video below shows some great examples of the uncanny valley:
Mori’s original hypothesis states that as the appearance of a robot is made more human, some human observer’s emotional response to the robot will become increasingly positive and empathic, until a point is reached beyond which the response quickly becomes that of strong revulsion. However, as the robot’s appearance continues to become less distinguishable from that of a human being, the emotional response becomes positive once again and approaches human-to-human empathy level. This area of repulsive response aroused by a robot with appearance and motion between a “barely human” and “fully human” entity is called the uncanny valley. The name captures the idea that an almost human-looking robot will seem overly “strange” to some human beings, will produce a feeling of uncanniness, and will thus fail to evoke the empathic response required for productive human-robot interaction.
A number of films that use computer-generated imagery to show characters have been described by reviewers as giving a feeling of revulsion or “creepiness” as a result of the characters looking too realistic. Examples include:
- According to roboticist Dario Floreano, the animated baby in Pixar‘s groundbreaking 1988 short film Tin Toy provoked negative audience reactions, which first led the film industry to take the concept of the uncanny valley seriously.
- Several reviewers of the 2004 animated film The Polar Express called its animation eerie. CNN.com reviewer Paul Clinton wrote, “Those human characters in the film come across as downright… well, creepy. So The Polar Express is at best disconcerting, and at worst, a wee bit horrifying.”The term “eerie” was used by reviewers Kurt Loder and Manohla Dargis,] among others. Newsday reviewer John Anderson called the film’s characters “creepy” and “dead-eyed”, and wrote that “The Polar Express is a zombie train.” Animation director Ward Jenkins wrote an online analysis describing how changes to the Polar Express characters’ appearance, especially to their eyes and eyebrows, could have avoided what he considered a feeling of deadness in their faces.
- In a review of the 2007 animated film Beowulf, New York Times technology writer David Gallagher wrote that the film failed the uncanny valley test, stating that the film’s villain, the monster Grendel, was “only slightly scarier” than the “closeups of our hero Beowulf’s face… allowing viewers to admire every hair in his 3-D digital stubble.”
- In the 2010 film The Last Airbender, the character Appa, the flying bison, has been called “uncanny”. Geekosystem‘s Susana Polo found the character “really quite creepy”, noting “that prey animals (like bison) have eyes on the sides of their heads, and so moving them to the front without changing rest of the facial structure tips us right into the uncanny valley”.
By contrast, at least one film, the 2011 The Adventures of Tintin, was praised by reviewers for avoiding the uncanny valley despite its animated characters’ realism. Critic Dana Stevens wrote, “With the possible exception of the title character, the animated cast of Tintin narrowly escapes entrapment in the so-called ‘uncanny valley.'” Wired Magazine editor Kevin Kelly wrote of the film, “we have passed beyond the uncanny valley into the plains of hyperreality.”