The creak of the door, the footsteps down the hallway...it's the buildup of suspense that really gets us going.
Indiana University telecommunications professor Andrew Weaver has studied both the physiological and psychological effects of horror movies.
"We're not talking about trivial effects here," Weaver said. "Things that went away after the movie, these are things that stuck with people and fear probably more than any other media effect is really persistent."
But why? Why do we put ourselves through this? Prof. Weaver says one reason is that there's a social nature to horror movies.
"People don't watch horror by themselves, you always watch in a group, and some have argued that this has become a rite of passage for males in particular," he said.
He also argues viewers subconsciously seek out traditional gender roles by watching scary films.
"There's a great set of studies done here at Indiana where they had a male and a female watch horror films together, and when the female was a part of the experiment the male would watch it if the female appeared uncomfortable, squeamish, unhappy with the content, then the male enjoyed the movie more and rated the female as more attractive," Weaver said.
And vice-versa: If the man appeared frightened, the woman would enjoy the movie less, and find her companion less attractive. Weaver also said the popularity of horror movies goes up when there's societal unrest, such as war or an economic crisis.
"We want to experience these frightening things in a way that we still have some control over it," he said. "We don't have control over scary things that happen in real life. But a mediated experience, a movie in a theater, we know it's going to end, we know at some level that we're safe, we can't be hurt by it, and so we can be scared and experience that action, but we maintain control over it."
Ao what makes us scared? According to Weaver, it's not really about gore -- it's all about suspense.
"When you leave it up someone's imagination, we can conjure things that can frighten us much better or effectively than what most filmmakers can invent and put onscreen," he said.
The use of music also builds dread, Weaver noted.
"Even different chords can elicit different emotions in people, when you hear the minor key and that sets up certain expectations of what might happen."
For instance, think of the "Jaws" theme, where the music almost became a character itself. And fear also comes down to what sticks with you long after you've left the theater -- maybe something you watched as a child, during those formative years.
"I watched "It," which is based on a Stephen King book, and i probably watched it a little too young," said IU junior Liz Zabel "It definitely left an impression on me and now i'm not necessarily terrified of clowns but I'm definitely a little sketched out."
IU professor John Clark is a little more old school with his fears.
"I'm an old guy, so "House of Wax" with Vincent Price was one of the scariest movies, it was one of the first 3-D movies, there were heads falling off -- right into your lap, in the popcorn...heavy stuff," Clark said.
IU's Weaver points out fear, as an effect, is one of the most long-lasting and powerful emotions -- making an impact days, weeks, even years later.
