9. Buzzing Bee Sound Effects Make You Subconsciously Anxious - The Exorcist
William Friedkin's The Exorcist is one of the greatest and most unnerving horror films of all time, in large part due to the anxiety-inducing atmosphere director William Friedkin generates.
It's well-documented that Friedkin included "subliminal" imagery throughout the film, namely brief flashes of demon Pazuzu's terrifying face, to keep the audience thrown off-kilter, but he also employed more subtle techniques to get the hairs standing up on viewers' necks.
In many of the film's earlier scenes, Friedkin integrated the sly sound of buzzing bees in order to induce a primal fear response in the viewer's lizard brain. You may feel uncomfortable during these scenes but not really know why.
Friedkin claims he also added "disturbing industrial sounds" into the soundscape of the demon scenes, in an attempt to trigger audience members' fight-or-flight response and make them feel a sense of impending danger.
As much as viewers might take umbrage with a filmmaker toying with their subconscious in such a way, it's undeniably genius-level cinematic manipulation.