Gatsby believed in the green light, the orgastic future that year by year recedes before us. It eluded us then, but that’s no matter - tomorrow we will run faster, stretch out our arms farther… And one fine morning - So we beat on, boats against the current, borne back ceaselessly into the past. - The Great Gatsby

Primal Scream: An Evolutionary Perspective on Horror Movies

I love scary movies. I can’t help but devour anything spooky and macabre, inevitably finding myself plagued by fearful images as soon as darkness falls or I find myself alone. The negative side effects do little to discourage me from watching these movies. Why weirdos like me find such enjoyment in horror is a question frequently posed in cultural discussions, and there are a great many theories. However, I find the question of why certain things frighten us just as interesting. There are few things more satisfying to experience in cinema than a good scare. When it’s done right, it almost seems like a magic trick, and like magic tricks themselves, the success of a horror movie relies on the tendencies of the human brain to react predictably to certain stimuli.    

Anyone who has a passing familiarity with the genre will recognize certain elements that are used consistently in horror movies to scare their audiences. So what is about these things that are so good at scaring us? The emotional experience of fear is built into our genetic history, from the early days when we were at the not-so-top of the food chain. Fear is a signal to our primal brains that our lives are somehow in danger. We fear the dark because our vision is compromised when night falls, leaving us more vulnerable to attack. We fear snakes and spiders because we know that some of them carry deadly venom in those creepy little bodies. We can look to Darwin for an explanation of why these fears are so universal, even in modern American society, where we are arguably safer than we’ve ever been. The ancient humans who didn’t experience fear of the dark wandered too far from the campfire and were eaten by predators, never getting a chance to pass on their lack of common sense to future generations. The fear instinct allowed our ancestors to survive, and so it has been passed on to us, thousands of years later. Evolution favors the scared.

There is an entire branch of psychology related to these kinds of theories, called evolutionary psychology: an attempt to explain human psychological traits as useful adaptations that have survived through natural selection. Much of what frightens us in horror movies can be linked with evolutionary theories. A recent article/podcast in Slate gave fascinating insight into the elements of musical scores in horror movies that are linked to our ancient survival impulses, therefore elevating our emotional experience. According to the author, there are two fundamentals to scary music: screeching, erratic tones, and low, grumbling ones. The first type of noise is reminiscent of screaming, or an animal in distress. The most obvious and perfect example of this is, of course, the music that accompanies the shower scene in Psycho. In my opinion, however, there is none more creepy than the music in Kubrick movies, in particular The Shining (vocals kick in around the 1:40 mark) and 2001: A Space Odyssey. In these scores, we have actual vocalizations, not just instruments imitating them. The worst part is the crescendo they keep building towards, as if you are drawing closer and closer to the source of the noises, when all you want to do is run away.

In contrast, low, rumbling tones scare us because the body mass of an animal directly determines the lowest frequency they can vocalize. Therefore, when we hear a low frequency, we think: there is something large nearby that is coming to get me. Again, there is a gold standard, obvious example for this: John Williams’ unforgettable theme to Jaws, the baritone piano keys leading the suspenseful orchestral build-up; the very audible embodiment of a shark’s primal predatory instinct. The soundtrack to the movie Donnie Darko, which makes use of encroaching, pulse-like low frequencies, also comes to mind as a great example of this kind of dread-invoking music.

Continuing in the evolutionary/lizard brain vein, another aspect of horror psychology that has always fascinated me is the fear of the unusual, especially when it comes to the appearance of human beings. We dislike seeing anything that looks pretty much like a human being, but something is slightly…off. Take the image of Samara, the girl from The Ring, emerging from a well. Yes, it’s a human being, but the thick black sheet of dirty hair that hides her face is absolutely terrifying, not to mention that she just generally looks like she’s decaying. Or Michael Myers, the serial killer of the Halloween movies, in his rubber mask. The appearance of this character is so effectively creepy, I think, because the mask is meant to look like an actual human face (it was originally a William Shatner mask), but the uncanniness is accentuated by the fact that was spray-painted white, and no eyes are visible underneath: just two black sockets staring you down right before the stabbing begins.

Interestingly, a great deal of classic movie ghouls fit the typecast of the Slightly Off Humanoid (SOHs, I call them): vampires, Frankenstein’s monster, zombies and mummies all fit the bill. So, what’s going on here? We’ve gotten this far in our evolutionary development in no small part to our use of stereotypes, which historically have helped us to make snap judgments that could spell the difference between life and death. To an early human, a person who looks strange or is acting strange is most likely sick, meaning they could infect you, or wounded, meaning a predator could be nearby to get you next. Your instinct is to get away as fast as possible. That may be why the slow, jerking gait of a zombie is frightening- that could be a neurological disease at work. And technically all of the above scary things are (un)dead -so fear of death is pretty obviously at play here.

Interestingly, I think that the fear that we experience in seeing something that looks diseased is distinctly different than the fear upon seeing something big, monstrous, and lethal. Big monsters trigger a fight-or-flight type stress response that comes to its highest point as the monster is being hinted at, before it is actually revealed- think of the stomping sounds/ripple in the water before the T. Rex appears in Jurassic Park, or the gigantic fin cutting through the water in Jaws (Spielberg gets it right, every time). You know there is something big and scary coming for you, but there is still time to get away. The result is that your sympathetic nervous system goes into overdrive and adrenaline races through your body. This may be why monster movies are generally considered a lot more fun than other types of horror- this is why you see King Kong, Jaws, and T. Rex in your Universal Studios rides, and not The Thing or Nosferatu. These type of diseased creatures of horror prey upon our emotions in a much subtler way, evoking the existential dread of unseen, unstoppable forces which we do not understand and therefore cannot outwit. And then we have slasher films, which it could be argued bridge the gap between these two categories. The classic movie serial killer is a huge, muscular man with extreme, sometimes supernatural strength- and he is almost always masked, lending the element of the unusual, unnerving physical appearance. Jason Voorhees, Michael Myers, the Scream ghost, and Leatherface all qualify here. Not being able to see someones face automatically means something is wrong, probably because human beings get most of their information about someone’s intentions by way of facial cues. All of this boils down to one simple point- we are terrified of the unknown.

Of course, biology and evolution can’t explain everything about why horror movies affect us in such profound ways- there’s also things like storytelling and artistic vision to consider. But it is interesting to consider how movies that seem so abstractly terrifying can all be linked, in some way, to the ancient past, when humankind was in it’s infancy and our safety was never a guarantee.