Human robot experienced as creepy

Robots come in all shapes and sizes. For instance, the healthcare robot is a small, plastic doll that laughs and talks to the elderly: everything to be good company. There are technology companies that take this some steps further and market artificially-intelligent robots that can barely be distinguished from humans. Is such a human-passing robot an improvement for the interaction between human and robot? No, say researchers from Utrecht University in the online magazine Frontiers in Psychology. Their research is the first survey into robots that were developed for interaction with humans.

Experimental psychologist Marnix Naber shows in his research, that he carried out with collaboration from students Anne Reuten and Maureen van Dam, that ‘almost’ human is not enough for the acceptance of artificial intelligence in our daily lives.


Naber had people look at various pictures of robot faces for his research, faces that differed from each other in terms of human resemblance. One of the robots he showed was the iCat, a robot developed by Philips, that does not resemble a human but a cat from a cartoon. And he also showed Saya to his subjects, a very human robot developed at the Tokyo University of Science. Naber's comments on the research results: “The more a robot resembles a human, the more normally the human responds to the robot.”


But there is a catch, according to Naber: “When a robot looks almost, but just not exactly enough, like a human, something strange happens. The close-to-human robot is then experienced as creepy, like there's something wrong with it. This creepy gut feeling was confirmed by a divergent change in pupil responses we saw in our subjects.”

We still have a long way to go before we accept human robots.


Scientists have predicted before that close-to-human robots can be experienced as creepy. This phenomenon is called the uncanny valley hypothesis. Naber's research confirms this hypothesis. The Utrecht-based researcher suggests that, if we want to successfully interact with robots, future robots should be indistinguishable from real humans. “We still have a long way to go before we accept human robots. In order to speed up the development process, robot designers could use the pupil response of humans as an objective test for successful interaction with robots. Until then, companies that aim for the interaction between humans and robots would be better off marketing non-human robots.”

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