Fear And The Physical Connection
It’s dark out, and you’re home alone. The house is quiet. You see it and hear it at the same time: The front door is suddenly thrown against the door frame. Your breathing speeds up. Your heart races. Your muscles tighten. A split second later, you know it’s the wind. No one is trying to get into your home. But for a split second, you were so afraid that you reacted as if your life were in danger, your body initiating the fight-or-flight response that is critical to any animal’s survival. But really, there was no danger at all. What happened to cause such an intense reaction? What happened was fear.
What is Fear?
Fear is a chain reaction in the brain that starts with a stressful stimulus and ends with the release of chemicals that cause a racing heart, fast breathing and energized muscles, among other things, also known as the fight-or-flight response. The stimulus could be a spider, a knife at your throat, an auditorium full of people waiting for you to speak or the sudden thud of your front door against the doorframe.
The brain is a profoundly complex organ. More than 100 billion nerve cells comprise an intricate network of communications that is the starting point of everything we sense, think and do. Some of these communications lead to conscious thought and action, while others produce autonomic responses. The fear response is almost entirely autonomic: We don’t consciously trigger it or even know what’s going on until it has run its course.
The process of creating fear takes place in the brain and is entirely unconscious. There are two paths involved in the fear response: The low road is quick and messy, while the high road takes more time and delivers a more precise interpretation of events. Both processes are happening simultaneously.
The idea behind the low road is “take no chances.” If the front door to your home is suddenly knocking against the frame, it could be the wind. It could also be a burglar trying to get in. It’s far less dangerous to assume it’s a burglar and have it turn out to be the wind than to assume it’s the wind and have it turn out to be a burglar. The low road shoots first and asks questions later. For most people this is the road most travelled- Knee Jerk Highway.
The high road is much more thoughtful. The high road considers all of the options. Is it a burglar, or is it the wind? “Have I seen this particular stimulus before? If so, what did it mean that time? What other things are going on that might give me clues as to whether this is a burglar or a wind storm?” Your senses might pick up on other data being relayed through the high road, like the tapping of branches against a window, a muffled howling sound outside and the clatter of patio furniture flying about. Taking into account this other information, the high road determines that the door action is most likely the result of wind. It sends a message that there is no danger and tells the brain to shut off the fight-or-flight response.
The sensory data regarding the door — the stimulus — is following both paths at the same time. But the high road takes longer than the low road. That’s why you have a moment or two of terror before you calm down.
Regardless of which path we’re talking about, all roads lead to the portion of the brain controls the ancient survival reaction called the fight-or-flight response.
To produce the fight-or-flight response, the hypothalamus activates two systems: the sympathetic nervous system and the adrenal-cortical system. The sympathetic nervous system uses nerve pathways to initiate reactions in the body, and the adrenal-cortical system uses the bloodstream. The combined effects of these two systems are the fight-or-flight response.
When the hypothalamus tells the sympathetic nervous system to kick into gear, the overall effect is that the body speeds up, tenses up and becomes generally very alert. If there’s a burglar at the door, you’re going to have to take action — and fast. Approximately 30 different hormones get the body prepared to deal with a threat.
The sudden flood of epinephrine, norepinephrine and dozens of other hormones causes changes in the body that include:
- heart rate and blood pressure increase
- pupils dilate to take in as much light as possible
- veins in skin constrict to send more blood to major muscle groups (responsible for the “chill” sometimes associated with fear — less blood in the skin to keep it warm)
- blood-glucose level increases
- muscles tense up, energized by adrenaline and glucose (responsible for goose bumps — when tiny muscles attached to each hair on surface of skin tense up, the hairs are forced upright, pulling skin with them)
- smooth muscle relaxes in order to allow more oxygen into the lungs
- nonessential systems (like digestion and immune system) shut down to allow more energy for emergency functions
- trouble focusing on small tasks as the brain is directed to focus only on big picture in order to determine where threat is coming from (thats why the victims can never seem to get the key into the ignition in a horror movie!)
All of these physical responses are intended to help you survive a dangerous situation by preparing you to either run for your life or fight for your life (thus the term “fight or flight”). Fear — and the fight-or-flight response in particular — is an instinct that every animal possesses.
At the moment we are threatened, we have increased strength, power, heightened senses and intuition. This increase in mental and physical capacity is commonly referred as an “adrenaline rush.” It is named after the primary hormone involved.
Some people actually enjoy the physical sensations that can accompany being scared — from the adrenaline rush to the racing heart to the perspiring palms. In his studies of people who thrive on riding roller coasters, “there’s almost nothing else that can match it in terms of the incredible sensory experience that the body is put through.”
The hormonal reaction we humans get from responding to a threat or crisis is what motivates us to “like to be scared”.