What do the top rated horror movies all have in common?
They all have unforgettable soundtracks that bring about an instantaneous feeling of fear. In fact, if you view the films without any sound, they become a lot less scary.
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 respond with fear?
The Fear Response
With respect to evolutionary biology, there’s an evident survival advantage to the instantaneous identification of a hazardous circumstance.
Thinking takes time, especially when you’re staring a hungry lion in the face. When every second counts, you don’t have the time to stop and process the information consciously.
Considering it takes a bit longer to process and contemplate visual information, the animal brain is wired to react to faster sound-processing mechanisms—a characteristic that provides survival advantage and has been selected for in the wild.
And that’s exactly what we see in nature: numerous vertebrates—humans included—generate and respond to harsh, nonlinear sounds and vocalizations when alarmed. This creates a virtually instant feeling of fear or anxiety.
But what is it about nonlinear sound that makes it frightening?
When an animal screams, it produces a scratchy, irregular sound that stretches the capacity of the vocal cords beyond their normal range.
Our brains have evolved to discern the properties of nonlinear sound as unpleasant and suggestive of life-threatening situations.
The fascinating thing is, we can artificially simulate a variety 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 manufacture scarier movies.
Music and Fear
We all know the shower scene from the classic film Psycho, and it’s certainly one of the most frightening scenes in the history of film.
But if you view the scene without sound, it loses most of its affect. It’s only when you incorporate back in the high-pitched screeching and bone-chilling staccato music that the fear response becomes fully engaged.
To reveal our instinctive aversion to this nonlinear sound, UCLA evolutionary biologist Daniel Blumstein carried out a study assessing the emotional reactions to two types of music.
Study participants listened to a collection of emotionally neutral music scores and scores that included nonlinear elements.
As expected, the music with nonlinear characteristics aroused the strongest emotional reactions and negative feelings. This response is simply part of our anatomy and physiology.
Whether Hollywood understands this physiology or not, it knows instinctively that the use of nonlinear disharmonious sound is still the best way to get a rise out of the viewers.
Want to witness the fear response in action?
Check out these 10 Essential Horror Movie Scores.