If you type “uncanny” into Google, the top results will be several references to the “Uncanny Valley”. This is an idea put forward in 1970 by Japanese roboticist Masahiro Mori concerning the appearance of robots, and how the more human they look, the more we accept them, but only up to a certain point. When the robot looks too much like a personal, and yet seems different on a fundamental level, our reaction becomes negative. It suggests that the distortion of the familiar can be more disturbing than the unknown.
Freud refers to the uncanny feeling of doubt when we can’t tell “whether a lifeless object is really alive; or conversely, whether a lifeless object might not be in fact animate”. He’s talking about our reaction to “waxwork figures, ingeniously constructed dolls and automata”, but of course now the uncanny valley has implications for the creation of film and game computer generated imagery, and relates not only to appearance, but also sound and movement.
Michael Stevens discusses the uncanny valley in his video “What Makes Things Creepy?” Have a look here – most entertaining!