During Halloween time, we’re confronted with a lot of images and experiences meant to terrify us. Some of the things we encounter are objectively terrifying. For example, it’s not hard to understand why a man in a hockey mask holding a chainsaw evokes a feeling of fear when we see it. While many of our scary Halloween paradigms are objectively frightening, there are many prototypical Halloween characters that we find quite creepy, even though they are not necessarily objectively terrifying. For example, this weekend I took my teenage son to a haunted house, and the whole way there he kept saying, “I hope there’s no clowns… I hope there’s no clowns…”. Many people can relate to this — feeling that clowns are just creepy and frightening — but why? Clowns, as well as several other scary Halloween characters like zombies, don’t display the clear signs of danger that are designed to frighten us, so why do we find them so creepy?
An answer to this question comes from a better understanding of the way our brain processes interactions with social targets. Specifically, research exploring the way that humans interact with machines and AI has documented the phenomenon known as the Uncanny Valley, and the Uncanny Valley can help explain our aversion to Halloween characters like clowns and zombies. What the Uncanny Valley tells us is that there is a positive linear relationship between how human-like something is, and how comfortable we are interacting with it. So, we find it more comfortable to interact with a lifelike cartoon character than we do with a stick figure, because a lifelike cartoon is more human-like than a stick figure. Similarly, we find it more comfortable to interact with a real human than we do a lifelike cartoon character, for the same reason. Essentially, the more human-like something is, the more we like interacting with it — with an important exception.
The term Uncanny Valley refers to a steep drop in our comfort interacting with something that is nearly human, but not quite. A good example of the Uncanny Valley and how it informs the way we experience social targets is the CGI movie The Polar Express. The CGI characters in The Polar Express were quite human-like; yet they still lacked realism on several important dimensions, and many people were left with the feeling that the movie was “creepy” and “terrifying”. This state of being nearly human-like, but not quite, is actually worse than being clearly un-human. For example, normal cartoon characters, which are far less human-like than the CGI characters in The Polar Express, are generally not considered creepy. This highlights how it’s almost human, but not quite, that we have trouble with.
And, this can help explain why we find certain Halloween characters, like clowns and zombies, so downright creepy! Clowns, for example, are nearly human-like, but because of their face paint, and in some cases the way they move and talk, they often seem not quite human. Similarly, zombies, who have many human-like features but typically move somewhat differently than humans and in many cases have different eyes than a real human, also fall into this “almost there but not quite” area. Additionally, in some scary movies, the scary character looks human-like, but moves differently. For example, stop-motion techniques can make it look like a character is moving too quickly, or too slowly (or both). We find this scary for the same reason the Uncanny Valley says we should dislike clowns — because the character moves in an almost (but not quite) human-like way.
In short, research on human-machine interactions has documented the phenomenon of the Uncanny Valley, which describes how we are uncomfortable interacting with entities that are nearly human but not quite. We’re actually more comfortable interacting with entities that are less human-like, because they don’t trigger our expectations that the entity should look and act like a real human (i.e., it’s clear to us that Homer Simpson isn’t a real human). This phenomenon can help us understand why we find clowns and zombies so creepy, because they are pretty close to human, but not quite.
References
Burleigh, T. J., & Schoenherr, J. R. (2015). A reappraisal of the uncanny valley: categorical perception or frequency-based sensitization?. Frontiers in Psychology, 5, 1488.