Halloween is upon us, and with it comes a slew of horror movies from spooky to downright horrifying. Which ultimately begs the question, why do people love horror so much?

Horror movies are so terrifyingly effective because, on a subconscious level, your brain thinks you’re actually about to be murdered. When you’re sitting and watching a screen, the motor regions of your brain turn off as your body relaxes. But on a conscious level, your brain is aware that this movie isn’t real life.

Why do we love horror movies so much? Warner Bros. Pictures

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Scary movies bypass the conscious parts of the brain to tap directly into the fight or flight response. It begins in the amygdala, which evolved to respond immediately to anything that looks like a threat, regardless of how real it actually is. The amygdala sounds the alarm to your body, first activating the hypothalamus, which tells your adrenal glands to inject you with a big boost of adrenaline. This causes the heart to pump faster and faster, delivering more oxygen to the muscles in case you need to fight something or run away.

The Exorcist may not be real, but your brain isn’t going to take any chances.

The most effective element of a horror movie, though, isn’t even the on-screen monsters, but rather the background music. The screechy, discordant, non-linear noises that build and crescendo sound enough like a baby’s scream that they activate the same genetically hardwired response pathway that a wailing child does.

However, despite the cold sweats and lingering nightmares, there’s still a high demand for horror. Scary movies alone have made billions of dollars in ticket sales since Frankenstein in 1931.

One possible reason for this is linked to addiction pathways. The adrenaline released from a fear response can cause a viewer to seek out that sensation again and again. Our love of all things horror may also stem from the Arousal Transfer Theory, suggesting that negative emotions created by scary situations can intensify the positive feelings we experience when the characters make it out alive.

Either way, the pure rush of adrenaline that horror movies evoke hasn’t stopped people from coming back for more.

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