Like how we evolved to have a stress response, we also evolved to have a more immediate response when our lives were threatened. This response is the emotional response we call fear. Due to the relative complexity of emotions, fear didn’t evolve until the brains of our reptilian ancestors developed.
Reptiles share with us, and most of the animal kingdom, a part of the brain known as the amygdala. The amygdala responds to immediate danger in the environment and mounts defences within the body to maximize our chance of survival. Throughout evolutionary history, reptiles who didn’t respond to threats in these ways were more likely to die and the ones that did had a better chance of surviving and reproducing. This tendency for more fear-prone animals to survive and reproduce led evolution to preference these animals, leading to the highly fear-prone humans we are today.
While the brain has evolved to have complex systems that allow for communication and social organisation, the amygdala has remained a relic of our reptilian days.
Amygdala Misfiring
Up until this point, we have been discussing the ways the amygdala can activate the emotional response of fear. However, the amygdala can respond to imagined threats or threats which may come in the future. This fear response to perceived or potential future danger is known as anxiety. So, anxiety is the fear of something which may or may not be an actual threat.
You can imagine anxiety like a home smoke detector. It’s designed to save your life in case there is a fire, however, sometimes it goes off when we burn toast. Anxiety can often lead us to forgo logic and become irrationally scared of benign stimuli.
Cognitive Anxiety
Although our furry friends also feel anxious, us humans have a way of making matters worse for ourselves.
If you’ve ever closely inspected your dog’s head amidst a “whosa good boy” head rub or a series of rapid-fire head kisses on your cat’s head, you may have had a similar thought to me: “Wow, your brain is so small.”
You can see in the following figure that we have a much larger prefrontal cortex (the part of the brain just behind the forehead). The prefrontal cortex gives us the ability to plan days, weeks, months, and years into the future and therefore can allow us to worry about events days, weeks, months, and years into the future.
This ability to worry about the future can imprison us with the ‘I better do this just in case’ thoughts that keep us stressed and the “what if” thoughts that keep us anxious.
We should appreciate that this ability to worry and plan for the future was adapted from our early human ancestors who had to survive in treacherous conditions.
For example, “What if a storm comes to destroy my shelter?” or “I better catch a second animal today in case I don’t have luck tomorrow.” After all, just like our evolutionary ancestors, early humans who had more of these worrying thoughts were less likely to die before having a chance to reproduce. So, our genetic ancestors were the worriers, the ones who needed to be ever vigilant, and the ones who planned for every contingency.
The reason these traits have persisted into an age where they are much less adaptive is because human society has developed extremely rapidly. While evolution has had hundreds of millions of years to hone the powers of our anxiety-mongering amygdala, it hasn’t had time to course-correct over the mere thousands of years in which agriculture, the manufacturing industry, legal systems, and healthcare have arisen.
So, our neurobiological responses to fear persist even though they rarely serve us today. Instead, anxiety often makes matters worse for us by placing our bodies under high levels of stress and can lead us to avoid what is meaningful for us in life out of fear.
Worse yet, we can become anxious about our anxiety. For example, “My heart is beating fast (from anxiety); I might be having a heart attack.” This leads to a more rapid heartbeat and stronger beliefs that you are experiencing the beginnings of a heart attack. For some people, this positive feedback loop of catastrophic interpretation of their bodily anxiety culminates in what is known as a panic attack (involving hyperventilation and dizziness).
This post is an excerpt from my ebook How to Live Stress-Free Life – 10 Proven Ways to Reduce Anxiety and Calm your Mind.
