What about "Horror" in Amnesia?

[Yuhaney]

What about the guy falling out of nowhere in the Kennels? Saw some Youtube vid with a guy totally shitting in his pants at that place.

I don't think it had that much to do with that it was a dead body.
For example, pretty much everyone have jumped for the part in Tech Demo, where Hunter is in the ceiling and it suddenly falls down.

When you are inside the game world and you are getting into the right feeling, and then something loud just happens, it makes the "jump" effect.

However, people are different.
Other people are more sensitive than the others. There for, there ain't the one and correct thing to scare everyone.
For example, someone does scare dead bodies (as said before), others don't. Someone gets almost heart attack when those screamers come and someone just doesn't scare, no matter what.