science of fear

On October 18th, 2017

The Haunting Science Behind Fear

You wake up in the middle of the night to complete darkness, not even a light from your phone, computer, or smoke detector glows. The air feels wrong and your gut tightens. You hear a low moan, then something as light as a spider web passes across your face. You don’t know what is going on, but you want out. In the blinding dark a cool hand covers your mouth and whispers in your ear, "Gotcha."
Okay, had enough of the creepy stuff? Or do you like being scared? Either way, we all know how it feels to be frightened, but why do we all feel many of the same things, and what’s the purpose of this interesting phenomenon? Let’s delve into the science of fear.

Why fear stuff?
Scientists believe fear exists to keep us alive, and it's been around for a very long time. Our prehistoric ancestors didn't have safe homes to live in and there were lots of big predators that liked the occasional human snack. No one had time to sit down and make a list of pros and cons about what to do when faced with a saber-toothed cat or a giant hyena. So, instead of the reasoning part of the brain being in control, the lizard brain takes over and initiates the fear response, an automatic reaction that helps keep our entire species alive. Before learning more about fear, check out this article from Smithsonian Magazine about the deadliest animals that ate humans.
There’s a lizard in my head?
There’s no reptile swimming between your ears, but when frightened, an ancient part of the brain dominates, one that controls our most basic instincts like fear, hunger, and the need to reproduce. It has been nicknamed the lizard brain. Even though this part of the brain evolved in our most distant ancestors, it still performs important functions involving messages and chemicals that are vital to our full body response to fear.

Fear on the inside
Your body’s central nervous system is designed to send and receive signals between cells or between parts of the body. Different parts of your brain are constantly receiving and processing sensory information from the outside world, as well as analyzing information about how your body is functioning on the inside. Neurotransmitters are chemicals that allow these messages to flow. Based on information received, your body may digest food, sneeze, or run a fever. When danger is perceived, the part of your brain known as the hypothalamus messages other parts of the body to release nearly thirty chemicals called hormones. This flood of adrenalin, cortisol and other hormones causes body changes that include:

  •  Dilated eyes. You can’t see your own eyes when you’re facing a potential threat, but your pupils get bigger to allow in more light. Like the wolf in Little Red Riding Hood, it is “all the better to see you with, my dear.”
  •  Increased heart rate. Your blood carries oxygen and nutrients throughout your body and removes toxins. When your heart is pounding, it is your body making the best use of its resources by circulating the blood as quickly as possible.
  • Improved lung function. The same goes for your lungs. Energy is diverted from some parts of the body to allow more oxygen into the lungs, which mean more oxygen in the blood, which means more oxygen gets to the muscles as they prepare to fight, flee, or freeze.
  • Tensed muscles. Tensed muscles are muscles with a lot of energy available to be released. Punching an opponent, running like the wind, or remaining absolutely till requires muscles to work at their peak. Even muscles just below the surface of the skin at the base of hair follicles tighten, making skin look bumpy. These goosebumps result in hair standing on end which makes us look bigger. This may not be as advantageous to us today as it was to our hairier, prehistoric ancestors, but every little advantage helps when confronting real danger.
  • Decreased function of nonessential systems. Digestion will or slow or stop when frightened. When the danger subsides, your body can get back to breaking down those tacos you had for lunch. Your immune system also takes a backseat during the fear response. Immunity helps keep you alive for a long time, but who cares about an infected hangnail when you are in immediate danger?
  • Inability to focus on small tasks. You need all your senses providing information at the big picture level to improve your chances of survival. Texting or touching up your nails will be nearly impossible to do when danger strikes.

There is a lot more to the fight or flight response than will fit here. For basic and fun information on the brain chemistry involved, explore this link , or use it as a starting point for your own deeper exploration. For a more adult treatment of how fear works, click here .

What about the psychology of fear?

Now things get a little tricky. Our emotions, perceptions, and cultural tendencies shape what we find fearful and the science of fear has been studied beyond an instinctual, pre-programmed response.
Sometimes people who have gone through a really terrifying experience claim time seemed to slow down, or things happened in slow motion. Scientists at the Baylor College of Medicine in Houston theorize that we remember scary stuff as lasting much longer than it really did because when the hypothalamus is activated during the fear response, it creates additional, richer memories in conjunction with our everyday way of processing and remembering the world. It is like the difference between remembering a vacation by looking at five still photos, or by browsing thousands of photos and some video clips from that same trip. Their findings are recapped in a LiveScience article .

Remember, the hormone adrenalin is partly responsible for that huge burst of energy, strength? People often experience a sense of well-being or invincibility as well. Some people start to crave the adrenalin high, and engage in increasingly risky behavior to reach the thrill. A subset of that group may become so focused on getting the rush that they lose all sense of personal safety. Injury or death may be the cost of adrenalin addiction.

Many people experience fear that has nothing to do with their physical safety, they are afraid of public speaking, of making a mistake in front of their peers or a teacher, or they run screaming from the room when they see a clown.

In the first two examples, recognizing that you are feeling fear, then using the accompanying energy surge can actually make you a better public speaker and less likely to make mistakes. Many actors and professional public speakers attribute onstage success to the prickly, energizing rush that comes with fear.

Then there are clowns. An irrational fear of anything is called a phobia, coulrophobia specifically, in the case of clowns. The emphasis is on irrational. You cannot deny the rational fear of being pinned to the ground by a five hundred pound bear, your body and your life are at risk. But being in the audience where there is a clown on stage, or seeing a picture of a spider online, or imagining being buried alive pose no real threats, but a lot of people feel otherwise. Sometimes those phobias are grounded in past traumas, sometimes they grow from cultural beliefs. Figuring out the why may require the help of an expert therapist, but before your session starts, click here for Oxford Dictionaries' list of phobias if you want to know see which ones you find frightening, or to learn some really long words.

A moderate amount of psychological fear is not harmful, and may even be good for you in the short term, helping you power through uncomfortable situations that are not life threatening. Some people even enjoy the heightened sense they get from watching a scary movie, riding a roller coaster, or visiting a haunted house.

However, when your perception of what is fearful becomes distorted and moves outside the norm, it can lead to many problems caused from too much time being spent ready to fight, flee, or freeze. Constant fear means your immune system is perpetually on hold, resulting in chronic disease. And distorted fears can result in significant emotional disorders that can take a huge toll on your quality of life.

So, fear is a natural part of life,and it often serves us well. Challenge yourself to learn more about the up side of fear to keep you safe, and how to manage the other side of fear to keep you sane. Attend our very own event Why Are You Afraid? The Science of Fear on October 27, 2017. For more information about this and other events, check out our website.

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