It's Halloween again, which means that across the country tonight folks will indulge in all kinds of terrifying pursuits from scary movies to haunted houses. It's fun, but if you think about it, it's also a little weird.

Fear shouldn't really be fun. The flight-or-fight response triggered by scary things - the pounding heart and sweaty palms we get when the girl in the movie is about to go into the dark basement - is the evolutionary legacy of our body's response to hungry lions and marauding enemies. At first blush, it would make more sense if we tried to avoid those experiences at all costs.

But we don't. A great many of us love to be scared (within reason). Why? The Atlantic's Allegra Ringo spoke with a "scare specialist" to find out. (Hat tip to Business Insider.)

Are you a dopamine junkie?

The basic appeal of your local haunted hay ride comes down to brain chemistry. When something terrifies us, our brains release a flood of the neurotransmitter dopamine. Some of us are simply wired to find that chemical zap enjoyable in the same way that so called "adrenaline junkies" enjoy the sensations engendered by extreme activities like skydiving or bungee jumping.

"New research from David Zald shows that people differ in their chemical response to thrilling situations. One of the main hormones released during scary and thrilling activities is dopamine, and it turns out some individuals may get more of a kick from this dopamine response than others do," Dr. Margee Kerr, the staff sociologist at haunted house ScareHouse, explains.

Evolutionarily, that may be down to the advantages of risk-taking. Exploring new territory, for instance, is scary, but can also pay off big time both in the distant past and today, so some among us developed a greater appetite for risk, an appetite we can feed with Halloween thrills.

Forging friendship through fear

The other reason many people love to be occasionally terrified is how the feeling works to build memories and bond us to others. "One of the reasons people love Halloween is because it produces strong emotional responses, and those responses work to build stronger relationships and memories," Kerr also notes.

In fact, if your date is a horror movie fan, choosing the slasher flick over the romcom might just work in your favor. Being scared releases "powerful hormones, like oxytocin, that are working to make these moments stick in our brain. So we're going to remember the people we're with. If it was a good experience, then we'll remember them fondly and feel close to them, more so than if we were to meet them during some neutral unexciting event," Kerr says.

Check out the complete interview for more details on the neuroscience, a rundown of all the ways people have historically tried to terrify themselves, and more detail on what type of situations exactly make for enjoyable fear.