I recently wrote a novel entitled The Proxima Plague and received a review that mentioned the novel as "horror". While I didn't think of the book as a horror story while writing it, I began to wonder: Why do we love scary stories? After all, our natural reaction to scary things is the so called "fight or flight" response: a surge of adrenalin which allows us to survive an existential threat by either runny away or attacking the peril head on. The threat may be dealt with but, afterwards we're left shaken and drained.
Some psychologists and aficionados of the genre would tell us that we enjoy them for the adrenalin rush similar to the feeling we get on riding a roller coaster with the near ninety degree drop. Afterwards we become more alive thanks to a quickened pulse and shaky knees. A different take on the after effects of that adrenalin rush. Or, it may be the closeness some couples feel after experiencing a horror movie. Yeah, who would have thought that watching Jason slice up a dozen or so bodies could be a bonding experience? An even darker explanation is we like seeing the blood and gore. Perhaps that's why each new generation of horror movies seems to ratchet up the cartoonish violence and body count over the previous crop.
There may be another reason for our love of fright: it helps us face our fears. Since we are thinking rational animals we learn from bad experiences. And I guess watching a scary movie or reading a horror novel could be classified as vicariously living through a bad experience. So, how does it help us face our fears?