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Why Does Stress Happen?

The body is designed to help people fight or flee for their lives. The fight-or-flight response is a primitive and automatic response to a perceived harmful situation or threat to our survival. This was a valuable function thousands of years ago when humans were chased by predators and needed to ramp up and muster all the energy and resources in the body to survive. Then once the threat disappeared, the body would calm back down.

It's not like that for us today, yet our bodies still respond to stress the same way. We are rarely chased by predators, but we do get stressed because we are stuck in traffic. We still have that fight-or-flight response when we encounter a stressful or harmful situation. If our bodies stay in that state longer, sometimes for hours, days or weeks at a time, we pay a physical price. Without proper time to recover from that massive use of energy, the body starts to break down and becomes weaker. That's why self-calming techniques are critical for those who struggle with stress or encounter it often.

The brain's role in stress

Our brain reflects the life we lead. How we behave and what we experience throughout our lives determine how the brain is wired – and often how we experience stress. While we talk about our brain as one big unit, it's important to understand there are a number of different parts that work together. Emotional parts can overpower – or even paralyze – thinking parts, sending our bodies into the fight-or-flight response.

An important part of the fight-or-flight response in our brain is the limbic system, where our emotional reaction to something takes place. The first thing that happens in this system is the processing of an event. If it's seen as stressful, the amygdala (a part of the brain that experiences emotions) sends a message to your hypothalamus (the part of the brain that controls basic body functions like body temperature and eating and sleep behavior) that something bad is happening. The hypothalamus then sends the message to the adrenal glands, which release a burst of energy and stress hormones to prepare us to fight or flee. At the same time, the amygdala tells the part of our brain that stores memories (the hippocampus) to remember what made us so stressed to begin with.

We can trigger this same fight-or-flight response just by thinking about a stressful situation. For instance, when we worry constantly about something or when we think about the same bad situation over and over again this can cause a vicious, stressful cycle for some people.

This is why it's important to know how to retrain these parts of our brains to respond to stressors in a healthy way.

The Limbic System graphic.
How your brain processes stressful events
Learn more – how to overcome stress

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