What Makes Zombies So Terrifying?

As the entertainment world's zombie outbreak continues unabated, one of the nation's top minds seeks an answer to a pressing question: What makes humans fear these brain-hungry abominations, aside from the whole brain-eating thing.

Stephen Schlozman, MD, knows a little something about fear and the undead. He's an assistant professor of psychiatry at Harvard Medical School, for one. He's also the author of The Zombie Autopsies, an upcoming work of fiction about a medical team on a remote island attempting to apply forensic techniques to the living dead in order to cure a zombie plague.

So Schlozman knows the human psyche, and he knows zombies. Who better qualified to tell us what about these shambling monstrosities terrifies us so?

According to Schlozman, writing in a blog post for Psychology Today, zombie terror stems from a very basic human information processing mechanism: Pattern recognition.

It's a mechanism we use every day, allowing us to quickly assess a given situation and respond appropriately. Our minds categorize situations and stimuli much like a computer does, and when we're presented with a situation, we bring up that data in order to react.

It's a mechanism that can be quite helpful. It's also a mechanism, as Schlozman points out, that can lead to prejudice.

Someone might expect that a man in a dark alley intends to take your wallet, and yet he might think the same of you. We make up our minds quickly in part because the drive to categorize and classify declares itself early and profoundly so we can get by in the world largely on autopilot.

What does this have to do with zombies? One of the key factors of zombie horror is forcing humans out of that autopilot state, presenting information our brains can't process through simple pattern recognition.

That guy is staggering, so perhaps he is drunk. But wait! That kid is also staggering, and kids don't get drunk. And that woman is staggering, and when was the last time I saw three staggerers at the same time? Things are not fitting into my usual patterns. I do not recognize this pattern, and I am therefore forced to switch off automatic and to perilously fly manually. Most of the time we're flying by instrument, but not now. Now, we need to look around.

It's this mix of the familiar with the unfamiliar that sets humans ill-at-ease, and the more the unfamiliar is mixed with the familiar, the more intense the feeling. Your brain is desperately searching for a pattern to grab hold of, yet there's nothing there.

Gimme something.

Anything.

And fear sprouts from the depths of your brain, your primitive cortex freaking the hell out and your frontal cortex madly searching the hippocampus for anything even remotely familiar.

And this is where you experience horror.

What an amazingly simple way to explain a complicated emotional and mental response. Consider your book preordered, Dr. Schlozman.

The Horrors, the Horrors! Meditations on the Science of Zombies and Fear [Psychology Today]