What do the top rated horror movies all have in common?
They all have memorable soundtracks that elicit an instantaneous sensation of terror. As a matter of fact, if you watch the films without any sound, they become a lot less frightening.
But what is it regarding the music that renders it frightening? More specifically, if sounds are simply oscillations in the air, what is it about our biology that makes us react with fear?
The Fear Response
In regard to evolutionary biology, there’s an evident survival advantage to the instantaneous recognition of a threatening scenario.
Thinking takes time, especially when you’re staring a ravenous lion in the face. When every second counts, you don’t have the time to stop and process the information consciously.
Seeing as it takes longer to process and ponder visual information, the animal brain is wired to respond to quicker sound-processing mechanisms—a trait that offers survival advantage and has been selected for in the wild.
And that’s exactly what we find in nature: several vertebrates—humans included—generate and respond to harsh, nonlinear sounds and vocalizations when frightened. This creates a nearly instant feeling of fear or anxiety.
But what is it about nonlinear sound that makes it scary?
When an animal screams, it produces a scratchy, irregular sound that stretches the capacity of the vocal cords past their normal range.
Our brains have evolved to identify the characteristics of nonlinear sound as abnormal and indicative of hazardous circumstances.
The fascinating thing is, we can artificially emulate a wide array of these nonlinear sounds to get the same instant fear response in humans.
So, what was once a successful biological adaptation in the wild has now been co-opted by the movie industry to produce scarier movies.
Music and Fear
We all know the shower scene from the classic movie Psycho, and it’s probably one of the most frightening scenes in the history of cinema.
But if you watch the scene on mute, it loses the majority of its impact. It’s only when you incorporate back in the high-pitched screaming and bone-chilling staccato music that the fear response becomes fully engaged.
To confirm our natural aversion to this nonlinear sound, UCLA evolutionary biologist Daniel Blumstein carried out a study investigating the emotional reactions to two types of music.
Study participants listened to a collection of emotionally neutral scores and scores that incorporated nonlinear elements.
As predicted, the music with nonlinear characteristics elicited the most powerful emotional reactions and negative feelings. This response is simply a part of our anatomy and physiology.
Regardless of whether Hollywood comprehends this physiology or not, it appreciates intuitively that the use of nonlinear discordant sound is still the best way to get a rise out of the audience.
Want to observe the fear response in action?
Listen to these 10 Essential Horror Movie Scores.