The Uncanny is a term very much used with zombie fiction, coming from Freud’s work. It’s about something so familiar and yet inherently wrong. Roboticist Masahiro Mori developed this further and designed the Uncanny Valley. We as humans can handle dolls or cartoons that emulate humans, but when we start getting to human-like robots, that’s the Uncanny Valley in which we are just straight grossed out and reject what we see. As the robots get more and more human with looks and reactions, we are more positive until a certain point and our reaction to it becomes complete revulsion.
I’ve only just started looking into the Uncanny and have more research to do, but that’s the basics of it.You can see zombies at the far bottom of the uncanny valley. You see a person you love, a person you know, but they are no longer who they once were. They are after your flesh. That screws with our perceptions. Some people have a similar reaction with mannequins (I have a mate who can hardly stand mannequins. They just freak him out.)
Here’s a video for funsies: