Roboticist Masahiro Mori conceived of the "uncanny valley" in his 1970 essay of the same name. Mori was originally concerned with the development of human-like robots, but his theory has since been expanded to explain the creepiness of everything from wax sculptures to computer generated imagery - anything that looks human, but not quite.
For the past five years, Stephanie Lay has been exploring the uncanny valley as part of her PhD research for Open University - recording her findings on her blog Almost Too Human and Lifelike For Comfort. Some consider Mori's uncanny valley to be a kind of vague pseudoscience rather than a proven scientific theory. Even Lay is not quite sure what to make of it.
"In the early part of my studies," says Lay. "I spent a while thinking about whether I should be using the term 'uncanny valley theory' or 'uncanny valley effect' or should it be 'idea?' 'Hypothesis?' 'Concept?'"
In spite of her uncertainty, Lay has yet to come across anyone who is immune to the effect, and when it come to uncanny faces people can detect minute flaws. In an entry on her blog, Lay discussed an "uncanny" image from the video game Assassin's Creed: "One respondent to the original post noticed that part of the wrongness of the image came from the fact that her eyes were actually mirrored, giving unrealistic reflective points in her eyes."
Artists regard these flaws as challenges to overcome, and researchers like Lay may play a role in helping them navigate beyond the uncanny valley. But is this territory we should be crossing?
During the 2000 Super Bowl, a company called Nuveen Investments aired a TV ad featuring the famous actor and quadriplegic Christopher Reeve. In the commercial, we see Reeve rise from his wheelchair and walk to the center of an amphitheatre, seemingly cured of his paralysis. The commercial was obviously computer-generated; there was something not quite right about the way Reeve moved and the look of his head during that close-up. And yet, after it aired, the National Spinal Cord Injury Association was inundated with calls from viewers who wanted to know how Reeve was cured. In spite of the "Uncanny Valley" effect of the computer animation, the television audience, fooled by the technology - or perhaps seeing what they wanted to see - believed Reeve had been cured.
Professor Philip Brey, Ph.D., is chair of the philosophy department at the University of Twente in the Netherlands. Brey is concerned with questions regarding the ethical implications of computing and information technology. And he has some concerns about how truly photorealistic CGI will be used in the future, especially in interactive entertainment.
"A potentially troubling development would be the use of photorealistic CGI characters that depict real persons without their consent," says Phillip Brey.
There are laws that are supposed to prevent the unauthorized use of a person's likeness, but, sometimes, determining ownership can be a muddy affair. And with the arrival of new technologies like photo-realistic CGI, the lines are even less clear.