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Key points
- Horror movies use sound to frighten audiences.
- We perceive some sounds as scary because we naturally associate them with danger.
- Horror movies take advantage of such biologically potent sounds.
By Frederik Lundsgaard Jensen, M.Sc. and Mathias Clasen, Ph.D.
The world is full of sounds, and sound can affect us greatly. Some sounds are pleasant, like the laughter of a small child or a babbling brook in a peaceful forest.
Other sounds are unpleasant, like the wailing of a child or the sound of nails on a chalkboard. And some sounds are decidedly scary, such as a piercing scream in a dark forest.
If you want to scare others, sound is a very useful tool. You probably know the classic prank where you hide behind a door or in a closet and wait for your victim to pass by.
When the timing is just right and the victim has their back turned, you jump out and yell Boo! It works every time.
There are also historical examples of sound being used as a psychological component in, for instance, rituals and warfare.
The Aztec’s so-called death whistles produce an unusually unpleasant sound reminiscent of a hoarse death scream. These whistles may have been used ritually or even in battle to scare the enemy.
During World War 2, the German Luftwaffe mounted sirens on their dreaded Stuka dive bombers. The sirens emitted loud, screeching sounds when the planes plunged to bomb or fire at the enemy. The point was to intimidate the enemy and break their morale.
In this post, we won’t be looking at death whistles, Luftwaffe sirens, or pranks, but at how sound works in horror movies – and why we are scared by different types of sound.
Without Sound, Horror Movies Are Just Boring
Horror movies show how efficient sound can be at provoking emotions, and one can hardly imagine a horror movie without sound.
Spielberg’s shark-infested classic Jaws would not be the same without the iconic soundtrack, which in the movie is associated with the arrival of the shark. And if you watch Stanley Kubrick’s masterpiece The Shining without sound the movie loses a lot of its effect.
In both Jaws and The Shining, sound is used to create both an ominous atmosphere and shock effects.
Think, for instance, of the famous scene from The Shining where little Danny Torrance rides his bike through the empty hallways of the hotel and ends up at the door of the haunted room 237.
In this scene, we hear the sound of Danny’s bike passing over wooden floors and carpets, but in the background, the so-called non-diegetic music – that is, background music which is not audible to the characters in the movie – is gradually getting louder.
The background music seems ominous and contains jarring elements, which are perceived as unpleasant (even by ‘tone deaf’ people; Cousineau et al., 2012) and clearly indicate that things are not as they should be.
If you watch the clip with sound, it is extremely unsettling, but if you turn the sound off, it’s just boring.
Sound Makes Us Jump from Fright
When horror movies create shock effects, such as ‘jump scares’ (where you ‘jump’ from fright), sound is typically a key element. Usually, the movie builds to the actual shock, which often consists of non-diegetic, ominous music followed by a very loud sound when the actual shock occurs.
For example, there is a scene in Jaws where a shark expert dives into a shipwreck and finds a very big shark tooth in a hole in the wreck.
The string music playing in the background is once again ominous. As viewers, we know that danger is afoot. Suddenly, a pale, decapitated, partly dissolved human head emerges in the hole. It’s a repulsive sight, but it is the loud, screeching sound of the violin that really creates a shock.
Screams Indicate Danger
Screams and scream-like sounds in particular play an important role in horror movies (Blumstein et al., 2010) and there are good biological reasons for that.
Researchers have shown that the scream has unique acoustic qualities that make it extremely effective as a signal of danger (Blumstein et al., 2012). Many animals scream when they are in danger.
The scream is the result of the animal straining its vocal cords and producing a so-called nonlinear and consequently unpredictable sound that is rough, discordant, and jarring.
The scream also has a much broader frequency spectrum, which includes the higher frequencies that vocal cords can produce, and are therefore more irregular and dissonant than speech.
A scream penetrates all other sound and mobilizes our attention at once. It is a fundamental biological signal that indicates someone is in danger, and we react instinctively to it.
Piercing Violins
One well-known horror movie trope is the scream queen, that is, an actress who is particularly accomplished in the art of screaming.
One of the legendary scream queens is Jamie Lee Curtis, who, for instance, screams for her life in John Carpenter’s trend-setting slasher 1978 film Halloween where she is hunted by iconic killer Michael Myers.
The music in horror movies can also imitate a scream. One of the most famous examples in cinema history is the so-called shower scene from Hitchcock’s classic Psycho.
In this scene, the main character (played by Janet Leigh, Jamie Lee Curtis’s mom, as it happens) is stabbed to death by an unknown assailant.
We hear her fear-inducing scream of death, but we also hear the sound of the composer Bernard Hermann’s famous violins that sound like a piercing scream.
People perceive such sounds as extremely unpleasant (Trevor et al., 2020) precisely because they are reminiscent of natural warning signals – just like the Aztecs’ death whistles.
Threatening Sounds: The Monster Is Coming
Very low sounds often appear in horror movies as well, both in background music and in sound effects. They can appear when a scary monster roars: the monster’s roar is almost always at a relatively low frequency.
If Godzilla squeaked like a mouse, it would be difficult to take the monster seriously. This is because we instinctively associate low-frequency sounds with danger.
The bigger the animal, the lower the sound it can produce (Bowling et al., 2017), and in the animal kingdom size is often associated with superiority and thus a threat. A very big gorilla is more dangerous than a tiny gorilla.
Similarly, you presumably try to produce a low-pitched Boo when you are doing a scary prank.
Some filmmakers have even experimented with so-called infrasound, which is sound at such a low frequency that we do not consciously register it.
We humans can hear sounds in a frequency range from approximately 20 Hertz (cycles per second) to 20.000 Hertz, but we can register sounds that are even lower.
When the violent movie Irréversible premiered at the Cannes Film Festival several audience members fainted. This could be because the director, Gasper Noé, allegedly inserted extremely low-frequency sound into the movie to disturb his audience.
Sounds that rapidly grow in intensity can also scare us and are frequently used in horror movies – for example, in nerve-racking scenes which are leading to a shock.
A quiet sound in the background which quickly becomes increasingly intense can create the sensation that something dangerous is on its way.
This is part one of a two-part series. The article is based on a Danish-language article also published in Danish on Forskerzonen at videnskab.dk. The text was translated by Majbritt Kastberg Grønbæk, to whom the authors extend their gratitude.
References
Blumstein, D. T., Bryant, G. A., & Kaye, P. (2012). The sound of arousal in music is context-dependent. Biology letters, 8(5), 744-747. https://doi.org/10.1098/rsbl.2012.0374
Blumstein, D. T., Davitian, R., & Kaye, P. D. (2010). Do film soundtracks contain nonlinear analogues to influence emotion?. Biology letters, 6(6), 751-754. https://doi.org/10.1098/rsbl.2010.0333.
Cousineau, M., McDermott, J. H., & Peretz, I. (2012). The basis of musical consonance as revealed by congenital amusia. Proceedings of the National Academy of Sciences, 109(48), 19858-19863. https://doi.org/10.1073/pnas.1207989109.
Neuhoff, J. G. (2016). Looming sounds are perceived as faster than receding sounds. Cognitive Research: principles and implications, 1(1), 1-9. https://doi.org/10.1186%2Fs41235-016-0017-4.
Trevor, C., Arnal, L. H., & Frühholz, S. (2020). Terrifying film music mimics alarming acoustic feature of human screams. The Journal of the Acoustical Society of America, 147(6), EL540-EL545. https://doi.org/10.1121/10.0001459.
