A rushing heartbeat. Sweaty palms. Your eyes dart, back and forth as your thoughts race a million miles a minute. Your legs twitch, itching to run. Your chest tightens and your throat chokes– getting ready to scream, or to cry.
These are the feelings of fear itself: the drowning panic that sets in when you’ve been spooked by a scary video, when you’re about to run from a spider or right before a big exam.
To you, these things all cross over into the fabulous realm of GTFO, but physiologically they’re all very different. Why would your heartbeat increase when you’re sitting in a computer chair? Why do you feel ready to run away from an English midterm, when what you really need is a focused mind and a solid understanding of the symbolism in Heart of Darkness?
The answer, of course, lies in the wonderfully weird and squishy world of human biology.
Back in the bad ol’ days, when your great-to-the-umpteenth-power grandparents had to get by on sleeping in caves and hunting for food, fear kept a human alive. The racing heartbeat, heightened senses and the urge to run all stem from what’s called the Fight or Flight Response.
During fight or flight, which all sufficiently advanced organisms experience, the animal’s body will prepare itself for one of two options when encountering a threat– fighting off the potential attacker or running the heck away. If one option is cut off– for example, if the animal is trapped– then it will instinctively go for the other. (This is why you should never corner a badger. It gets messy.)
All the standard biological responses to fear prepare the human body for this response. An increased heartbeat delivers more oxygen to the muscles, readying them for a tough battle or a quick dash. You sweat in order to preemptively cool down your body, since both fighting and running can cause you to overheat.
As your body shuts away blood from systems that aren’t immediate to survival, you get a sick feeling– it’s inhibiting the digestive system. You vision may blur as your pupils dilate– ready to take in the situation at a glance. And if you’re REALLY spooked, like at a haunted house, your body might just go for the lovely embarrassing route of making you pee your pants– a technique that deters both potential predators and potential dates.
The biological mechanism that makes the fight or flight response go ‘round is know as the Autonomic Nervous System. This is the nervous system that keeps all the squishy bits running– it makes sure that your heart beats, you stomach digests stuff and that you more or less don’t drop dead.
The autonomic nervous system is divided into two parts: the sympathetic system and the parasympathetic nervous system. Both these systems are totally different– they have different nerves branching from your spine, different entrances to cells, the whole shebang.
Your sympathetic nervous system is, well, sympathetic to your cause– so long as your cause is firmly in the ‘OH GOD THERE IS A CLOWN MUST RUN’ category. This is the system that fuels the fight or flight response– it tells your adrenal gland, located in the kidneys, to start pumping out adrenaline, which kick-starts the wonderful feeling of terror.
Your parasympathetic system works alongside your sympathetic system– that is to say, it arm-wrestles it for control over your bodily functions. It keeps your heart beating at the normal rate and controls stuff like the digestive system.
The two systems are constantly at odds with one another– one inhibits the function of the other. When you’re triggered by something that scares you, your sympathetic system takes over. As the feeling fades after the potential threat is gone, your parasympathetic takes the wheel and you calm down.
Of course, for all this science, it doesn’t explain why some people are just plain scared of seemingly innocuous things. Take clowns, for example. Yeah, they’re creepy– but why do we find them creepy?
There’s something in both the robotics and the CGI industry known as the ‘Uncanny Valley Effect.’ That is to say, there’s a steep valley between things that look convincingly human, and something that looks fairly like a human, but is just a little bit off.
A smiley face drawn on paper shouldn’t freak you out. Nor should a fairly realistic drawing. However, when you start looking at the ‘hyper realistic’ children from The Polar Express, your skin starts to crawl. It’s supposed to look human, but it isn’t. Frozen eyes, a fixed complexion, oddly paralyzed facial muscles– these all freak you the heck out.
Clowns, with their pallid makeup and ever-frozen smiles, fit the Uncanny Valley dip to a T. Their pale faces subconsciously look like corpses to us. The strange baggy clothing and the shambling walk are all terrifying, in an alien kind of way.
Of course, there are plenty more phobias than that. Arachnophobia is the fear of spiders– which can be justified if you live in a place as terrifying and deadly as Australia. Agoraphobia is actually classified as an anxiety order, when someone fears crowds and large open spaces.
The ultimate props, however, go to the person who decided on the name for the fear of long words: hippopotomonstrosesquipedaliophobia.
This should be somewhat comforting to the majority of you. No matter how much a biology midterm may scare you, at least you aren’t terrified of saying it aloud.
Weird Wednesdays 