Music has the potential to immensely affect and alter the moods, actions and decisions of people. However, this is not only true of humans; the right kind of music will even make a canine (and many other animals) start dancing, moving, and acting a bit “strange” on the sofa. Given that, there is little surprise that music is used to such a high degree in movies and TV shows to make certain shots and scenes seem more dramatic.
However, have you ever noticed that there are certain kinds of sounds, especially in horror movies, that give you the chills and have the potential to rob you of your sleep? Why do these sounds seem so scary?
Why Do Some Things Sound Unpleasant or Scary?
Movie makers (quite intelligently) exploit one particular propensity of the human brain to feel awkward or anxious when it detects certain kinds of sounds or music that are known as non-linear sounds. Non-linear sound waves are those that have a very high amplitude in comparison with the sounds produced by normal musical instruments, animals’ vocal cords and equipment used in movies. The other way of producing non-linear sound is to abruptly change the frequency of acoustic instruments.
A Particular Sound to Elicit Emotions
Scientists have observed that human minds are averse to certain kinds of sound, such as the one produced by marmots (an American ground squirrel). This aversion can be manifested in different ways according to the will of the movie maker to augment the cinematic effect of a particular scene, perhaps one featuring some sort of tragedy or emotional turmoil. The non-linear sounds help tremendously in these cases, as the two vital senses engaged in watching a movie, i.e., sight and sound, are used to their full potential to make the scene even more appealing and elicit various emotions from individuals.
Consider an example… you are thinking of a happy event from the past and at the same time, someone in the room plays a merry tune on the speakers. Wouldn’t you feel even more exhilarated? You would start tapping your feet, bobbing your head, and who knows, maybe even break into a few dance moves.
Identifying a Non-linear Sound
Sounds become non-linear as the volume is upped and the amplitude increases beyond ‘normal’ (this should be quite intuitive for acoustic geeks). “The same thing happens in your vocal tract. Indeed, you can imagine that if you’re really scared, you’ll really yell, and the yell or scream will contain non-linear noise,” says Daniel Blumstein, a professor and an evolutionary ecologist at the University of California at Los Angeles.
The Secret Weapon of Horror and Drama
Researchers analyzed more than 100 soundtracks to trace non-linear sounds across four major genres: adventure, horror, drama and war. Although non-linear sounds are used across all of these genres, their use is most pronounced in horror and drama. Whether it’s a scene where a zombie is just about to attack an unsuspecting protagonist or a shot where a couple is parting ways forever, non-linear sounds make the images even more captivating to the audience.
Next time you’re watching a movie and sense the background music rising dramatically, adding an enchanting effect, pat yourself on the back – now you know why those sounds make people get the goosebumps!