I used to do a lot of sound work on films. They were documentaries, but the tricks of the trade don't change a whole lot from one genre to the other. There's an image on the screen and there's a sound to go with it.
Back in Alfred Hitchcock's day, the speakers in the theaters were pretty dismal, compared to today's stereophonic digital blare. But, still and all, in his most controversial film, which was the scariest thing a lot of folks had ever seen at the time, Psycho, the sound effects had a lot to do with making the shower stabbing scene so frightening. Those violins screeching to a crescendo as you saw the knife being lowered into a naked girl; that was some pretty avant-garde stuff back then. Of course, it's been used and overused by now.
Probably no better example would be what you experience when you have the misfortune to pay for a ticket to see What Lies Beneath. Every time this hackneyed cliche of a film makes you jump, take a second to think about what just happened. Was it that you were so caught up in the action? Was it because your empathy with the character was a dissolving adventure?
Nope; it was because the speakers were screaming to you, "This is scary!!! Jump, dammit!!"
As many movie reviewers have stated, if this hadn't been made by Robert Zemeckis and hadn't starred Harrison Ford and Michelle Pfeiffer, this kind of would-be Hitchcock bullshit would have ruined some careers before they got out of the starting blocks.