The mechanisms of the brain, stress and our health

Stress can mean different things to different people as each of us may have a different response to any given stimulus based on many factors. We know stress is personal and subjective and yet inarguably one of the greatest influences over our health and well being. We also know that there are tools that help us change our perception and reaction to stressful stimuli therefore offering us more potential to shift the detrimental impact.
A stressful situation — whether something environmental, such as difficulties at work, or psychological, such as persistent worry about a loved one — can trigger a cascade of stress hormones that produce physiological changes.

This combination of reactions to stress is also known as the “fight-or-flight” response because it evolved as a survival mechanism, enabling people and other mammals to have a quick reaction to perceived life-threatening situations. The myriad hormonal/chemical changes and physiological responses can help a person to fight the threat or flee. As we now know, the body can also react to stressors that are not technically life threatening (such as disagreements, job pressure, and family struggles).

Over the years, researchers have learned not only how and why these reactions occur, but have also gained insight into the long-term effects stress has on physical and psychological health. Over time, repeated activation of the stress response takes a toll on the body. Research suggests that prolonged stress contributes to high blood pressure, chronic illness, inflammation, heart disease, obesity, early onset aging, dementia and also contributes to anxiety, depression, and addiction. And these are just naming a few. We are continually realizing the ramifications of ongoing stress responses to our health.

To understand stress we need to realize our brain/body complex has evolved through time to meet our ever-changing environments and what ‘survival’ has meant.
Our neural circuitry in the brain is designed to create ‘habits’ to make it easier for each of us to perform tasks without thinking. Each time you repeat a habit, whether a task, a perception, a thought, behavior or emotion, it becomes more engrained and unconscious. The same is true of the habit of stress.
Our stress and threat reactivity is partially shaped by our personal genetics and experiences but also by evolutionary biology. Believe it or not, our propensity to look for the ‘negative’ is a human trait we carry over from our early ancestors. The brain keeps us closely tuned in to what is ‘bad’ or potentially wrong in our lives to ensure our survival.
The brain is a critical hub on every level in our quest to survive. Without you realizing it, in the course of just one breath cycle, a quadrillion-plus messages/signals will cross your brain in roughly a tenth of a second. All our thinking, emotions, desires, bodily functions are courtesy of close to 1/1 trillion brain cells as they fire in our brains sending messages to other neurons. Basically the brain is a connection machine constantly moving information around.
Research is beginning to show us that much of this brain activity is dedicated in service to negative thoughts rather than positive. The reason for this can be found in our ancestry and need to survive. We needed our brains to constantly scan our surroundings for possible threats and if you weren’t diligent, you might not survive.

Technology has allowed us to actually see the functions of different parts of the brain and the roles they play. The amygdala (our alarm center) has two thirds of its cells dedicated to processing negative or potentially negative information. This part of the brain dates back to our reptilian predecessors and is often called the ‘lizard brain’. It differs from the pre frontal cortex that helps us stop, think and evaluate situations. The pre frontal cortex takes its time to evaluate data and make decisions. The amygdala scans moment to moment and makes fast snap judgments based on what is perceived as a threat. It is ‘hardwired’ to focus on the negative and quickly react.
Basically our brains categorize memories we have experienced as bad, threatening or unsafe and the amygdala stores them to be retrieved the next time a similar situation arises. This is a mechanism for keeping us safe.
Every day we are faced with trying to balance our brains deeply engrained evolutionary tendency to survive and see ‘threats’. This primal reaction is then intensified by our own unique life experiences (where ‘threats’ look different than tigers or finding food).

Stress stimulus→Brain→Nervous System→Physiological changes

The stress response begins in our brains. When we experience a perceived threat we send the information to the amygdala which will then instantly sends a distress signal to the hypothalamus.
The hypothalamus is a bit like a command center. This area of the brain communicates with the rest of the body through our autonomic nervous system, which controls such involuntary body functions as breathing, our heartbeat, blood pressure and the dilation of blood vessels in the lungs.  The autonomic nervous system has two divisions, the sympathetic nervous system and the parasympathetic nervous system. The sympathetic nervous system functions like a gas pedal in a car. It triggers the fight-or-flight response, providing the body with energy so that it can respond to the perceived threats. The parasympathetic nervous system promotes the “rest and digest” response that calms the body down after the danger has passed.

After the amygdala sends a distress signal, the hypothalamus activates the sympathetic nervous system by sending signals through the autonomic nerves causing a chain of physical reactions.
All of this happens so quickly that people aren’t even aware of them.

As the initial surge of chemicals subsides, the hypothalamus activates the second wave of the stress response system known as the HPA axis.

The HPA axis relies on a series of chemical/hormonal signals to keep the sympathetic nervous system, the “gas pedal”, pressed down. If the brain continues to perceive something as a threat, the body continues to stay revved up and on high alert. Stress responses can become a habit based on many factors and we end up day to day with the gas pedal pushed to the floor and we don’t even realize the impact it is having across the board on our health. Because every part of the body (and mind) are interconnected this constant stress reaction sets in motion so many of the health concerns listed above and so much more.

This practice can help you to relieve the stress response by understanding when it is activated and giving you tools to unwind the habit through Mind Mapping™ and how ‘stress’ can be any stimulus that directs the body towards fight/flight or imbalance. You will discover the power of your thoughts and emotions on the brain/body and tools for activating the parasympathetic nervous system…..otherwise known as rest and relax. We need to have a flexible nervous system for our health and well being and this practice empowers you to have more flexibility, insight and choice.

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