Stress - Fight or Flight with the Occasional Freeze
Ok, this is another big rock!!!! A stressful situation — whether something real, such as a looming deadline, the Covid virus, or something psychological, such as persistent worry about losing a job, boyfriend/girlfriend or whatever — can trigger a cascade of stress hormones that produce well-orchestrated physiological changes. A stressful incident can make the heart pound and breathing quicken. Muscles tense and beads of sweat appear. This is our good ole sympathetic nervous system.
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 react quickly to life -threatening situations. You have to run from that lion/bear/snake chasing you or turn around and fight it!!! The carefully orchestrated yet near-instantaneous sequence of hormonal changes and physiological responses helps someone to fight the threat off or flee to safety. Unfortunately, the body can also overreact to stressors that are not life-threatening, such as traffic jams, work pressure, and family difficulties. Americans are often running from the lion every day and all day long. That leads to chronic stress which is horrible for you.
You can also think something in your head and get the same response as you would if it is actually happening. I am so scared of heights, and one year, we went to the Grand Canyon and poor Clark tried to hike with me. I swear, just looking over the edge I got the same response as I would have had if I were falling over the edge!!! I was sweating and my heart rate went sky high. For heavens sake, I was sitting in the restaurant with a cup of coffee just thinking about the hike and broke out in a sweat. Needless to say, I felt so embarrassed (I also did not hike with my poor daughter). My son and husband went out on a hike, and I could get the same response when I thought about them on the edge of the canyon. The brain is a powerful organ!!! That is why anxiety is so bad. Fear is perceiving a real threat , but anxiety is worrying about the "what ifs". The brain reacts the same way.
I think there is another response as well. I think some of us just freeze. I am not sure if I would run from the lion; I would probably just stand there and get eaten. Those stress hormones are still running around my body and causing havoc. Think about when you have so much to do, but you just stand there and stare at the pile of to dos.
The autonomic nervous system has two components, 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 a burst of energy so it can respond to perceived dangers. The parasympathetic nervous system acts like a brake. It promotes the "rest and digest" response that calms the body down after the danger has passed.This all occurs without us even having to think about it.
When someone experiences a stressful event, the amygdala, an area of the brain that contributes to emotional processing, sends a distress signal to the hypothalamus which is an area of the brain that functions like a command center, communicating with the rest of the body and activates the sympathetic nervous system by sending signals through the autonomic nerves to the adrenal glands. These glands respond by pumping the hormone epinephrine (also known as adrenaline) into the bloodstream. As epinephrine circulates through the body, it brings on a number of physiological changes. The heart beats faster than normal, pushing blood to the muscles, heart, and other vital organs. Pulse rate and blood pressure go up. The person undergoing these changes also starts to breathe more rapidly. Small airways in the lungs open wide. This way, the lungs can take in as much oxygen as possible with each breath. Extra oxygen is sent to the brain, increasing alertness. Sight, hearing, and other senses become sharper. Meanwhile, epinephrine triggers the release of blood sugar (glucose) and fats from temporary storage sites in the body. These nutrients flood into the bloodstream, supplying energy to all parts of the body.which controls such involuntary body functions as breathing, blood pressure, heartbeat, and the dilation or constriction of key blood vessels and small airways in the lungs called bronchioles; so that the person has the energy to fight or flee.
All of these changes happen so quickly that people aren't aware of them. In fact, the wiring is so efficient that the amygdala and hypothalamus start this cascade even before the brain's visual centers have had a chance to fully process what is happening. That's why people are able to jump out of the path of an oncoming train even before they think about what they are doing.
As the initial surge of epinephrine subsides, the hypothalamus activates the second component of the stress response system — known as the HPA axis. This network consists of the hypothalamus, the pituitary gland, and the adrenal glands. You can even throw in the thyroid and gonadal (ovaries and testicles) hormones, as they are affected. The HPA or HPATG axis relies on a series of hormonal signals to keep the sympathetic nervous system — the "gas pedal" — pressed down. If the brain continues to perceive something as dangerous, the hypothalamus releases corticotropin-releasing hormone (CRH), which travels to the pituitary gland, triggering the release of adrenocorticotropic hormone (ACTH). This hormone travels to the adrenal glands, prompting them to release cortisol. The body thus stays revved up and on high alert. When the threat passes, cortisol levels fall. The parasympathetic nervous system — the "brake" — then dampens the stress response. Unless we stay constantly stressed and there is no "brake"!!
Constant epinephrine surges can damage blood vessels and arteries, increase blood pressure and raise the risk of heart attacks or strokes. Elevated cortisol levels create physiological changes that help to replenish the body's energy stores that are depleted during the stress response. But, they inadvertently contribute to the buildup of fat tissue and to weight gain. For example, cortisol increases appetite, so that people will want to eat more to obtain extra energy. It also increases storage of unused nutrients as fat. Over the years, researchers have learned not only how and why these reactions occur but have also gained insight into the long-term effects chronic stress has on physical and psychological health.
Over time, repeated activation of the stress response takes a toll on the body. Research suggests that chronic stress contributes to high blood pressure, promotes the formation of artery-clogging deposits, and causes brain changes that may contribute to anxiety, depression, and addiction. More preliminary research suggests that chronic stress may also contribute to obesity, both through direct mechanisms (causing people to eat more) or indirectly (decreasing sleep and exercise). We have to learn to put on the brakes somehow - particularly when the "lion" is in our head.
So what do we do??
Fortunately, people can learn techniques to counter the stress response.
It is called the Relaxation response.
This is the parasympathetic nervous system. Dr. Herbert Benson, director emeritus of the Benson-Henry Institute for Mind Body Medicine at Massachusetts General Hospital, has devoted much of his career to learning how people can counter the stress response by using a combination of approaches that elicit the relaxation response.
Once you practice these, it gets easier to learn to do this when you feel stress. It is a way to balance the parasympathetic and sympathetic system. You can get that blood pressure and pulse down.
These partially include:
Deep abdominal breathing exercises
Focus on a soothing word (such as peace or calm) also called a Mantra
Visualization of tranquil scenes or visual imagery (as it is frequently called)
Guided meditation
Traditional meditation
Prayer
Yoga
Tai chi
Gardening
It is different for everyone. I am not one of those people that can sit still, so I do better with moving meditation or even praying — like when I am running or walking. I also like guided meditation and visual imagery, because my brain can be all over the place if I am stationary. Both of those modalities have someone guiding you through the process.
Many people can sit quietly and just clear their mind. One of my classmates from my Integrative Medicine fellowship actually has a meditation room, and it is where she goes to clear her thoughts and relax.
My husband does it by being outside in nature. One of my best friends loves to garden.
You have to find what resonates with you!!!!
I promise I will go to all the various methods in future blog posts! This just give you the reasons why they are important.
All material gathered and researched through my amazing fellowship program, The Arizona Center for Integrative Medicine.
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