“Keep your friends close and your enemies closer”. Interesting quote to start off with, eh? Well, I’m calling out your brain, friend and enemy of you. When you go through trauma and stress, that brain can be a serious enemy if you don’t understand it, so that’s what we’re going to work on. I spent some time with Dr. Andrew Pleener and he was kind enough to write me out a breakdown of how our brains respond to stress. To understand it is to start controlling it. Even if it’s the first step on a 1,000 mile journey, at least your happy ass is walking. 

The Stress Response: a survival mechanism to help protect us from an acute threat (aka as the fight or flight response). Involves interactions between many CNS structures… one being the hypothalamic-pituitary axis (regulates our endocrine productions of cortisol and adrenaline). These are the hormones responsible for increased heart rate, increased breathing, pupillary dilation, constipation and urinary retention. In the event that we were being chased by a bear, we want to breath more to take in as much oxygen as possible, and we need our heart rate up to circulate that oxygen around to our organs / muscles, we need our pupils wider to see where we are going, we do not want to sleep until the threat is gone, and we want constipation/urinary retention because we want to get as far away as possible from the bear and then use the restroom once the threat is gone. But what if we experience this reaction due to the perception that something is a threat when in reality there is no actual threat present? It manifests as Anxiety (increased breathing and rapid heart), Light sensitivity (pupil dilation) , Poor sleep, Constipation/Urinary Retention (resulting in indigestion, bacterial overgrowth, weight gain, bloating, irritability, etc).

The Rest & Digest Response: Once the threat is gone, the stress response resolves. Cortisol and adrenaline are lowered and the “Rest and Digest Response” takes over. It is the complete opposite of the stress response. The bear is gone, we can now relax. Pupils become narrow because we afford to see less and it is now safe to sleep. Constipation and urinary retention are gone so we can finally use the restroom. We want to be more sexually active and develop salivation and tears. Heart rate slows, breathing slows and most of this is controlled by the Vagus nerve.

Vagus Nerve: Cranial Nerve 10. Originates in the medulla of the CNS, divides into two branches coursing down the neck towards the G.I tract innervating structures along the way and releasing a chemical called acetylcholine to carry out its actions. This innervates structures of the mouth, soft palate, pharynx , larynx, affecting speech, swallowing, social communication / expression. The nerve continues to innervate the heart, lungs, G.I tract to reduce breathing and anxiety, as well as increase G.I motility, reducing constipation and improving overall digestion.  The nerve also senses inflammation in the body and sends anti-inflammatory agents to the site.

4. Vagal Tone: The degree of action exerted by the Vagus nerve. When vagal tone is high, we tend to experience an increase in relaxation, sleep quality, improved social communication, and an overall reduction in anxiety, G.I complaints, Inflammation & medical illness. Additionally, heart rate is reduced and there tends to be more variations between heart beats. This is why vagal tone is measured by  determining Heart Rate Variability (HRV) with a higher HRV indicating greater vagal tonicity.

5. Loss of balance: The action of the stress response competes with the same organs that the vagus nerve innervates, but with opposite goals. As our levels of perceived stress increase, the action of the vagus nerve is offset by the intensity of the stress response and the scale begins to tip in favor of the stress response overall. This resulting decrease in vagal tone leads to difficulty with speech / swallowing (similar to during a nerve wracking presentation), decreased facial expression (loss of emotion/smiling as seen when scared), increased inflammation (more medical illnesses), decreased digestion (constipation, nausea, cramps, bloating), increased breathing, increased heart rate, resulting decreased HRV.

6. Perception: Lets take note that it is rarely the situation itself that elicits a stress response but rather it is the perception of a situation to be stressful that provokes it. A trauma is an event that someone experiences which changes the way that individuals perceive themselves and/or the world around them, making that person more likely to perceive routine situations as stressful. Example: If I was severely bit by a dog as a child and saw a dog in this room right now my automatic, subconscious pop up thought might be “I could potentially get bit.” Fight or flight slowly kicks in, cortisol and adrenaline goes up and my heart rate mildly increases, my breathing increases. If I had never been through the experience of getting bit, I would have avoided this reaction all together.

If I was emotionally bullied during my life by friends, family, and loved ones to believe I am no good, or unattractive and I call up a woman and she immediately states “I have to go and slams the phone down.” My automatic subconscious pop up thought if I have a core belief that I am no good or unattractive would be things like “she doesn’t like me, or maybe she is seeing someone else.” Cortisol goes up along with the feelings of hopelessness and worthlessness. If an identical clone of me grew up in a situation with a lot of love, praise , compliments, no bullying and never developed that core belief of not being good enough, the same situation might produce an automatic thought of “maybe her mother got sick and she had to go, I hope she’s okay,” and I person would experience empathy instead of sadness.

7. Trauma & How it Affects Perception: Trauma, whether it be divorce, abuse, bullying, witnessing a loved one get sick, etc  makes us more likely to perceive routine situations to be more stressful (having more automatic negative pop up thoughts that we can not control) . The negative core beliefs we develop as a result of trauma affects our self esteem, perception of self and causes us to have “ruminating” thoughts about our future / catastrophizing day to day events.

8. Result of Trauma (Plaque Analogy) : The chronic stress associated with day to day perceptions of stress (as a result of trauma) causes ongoing reduction in vagal tone and long term hormonal imbalances (starting with cortisol / adrenaline) that effects our brain and body physically over time. It is these changes that makes us experience new onset or exacerbated mental health issues.  Similar to how increasing plaque slowly blocks arteries until eventual heart disease / stroke develop. These chronic hormonal imbalances alongside reduction in vagal tone leads to the following physical changes:

a). Increased Cortisol & Adrenaline:  In addition to the symptoms mentioned above including gradual baseline increases in resting respiration rate and heart rate, photosensitivity (from pupilary changes), and constipation, chronic cortisol and adrenaline are associated with production of inflammatory cytokines (IL-1, IL-6, TNF alpha).

b). Increased inflammatory cytokines / Flu like symptoms: These inflammatory markers can travel from the periphery and enter into the central nervous system (CNS- your brain) through leaks in the blood brain barrier. Once the brain becomes inflamed, people develop symptoms similar to a common cold, or flu. When you get the flu, people develop malaise, weakness, poor concentration, low energy, changes in sleeping patterns, loss of appetite, loss of interest in hobbies.

c). Low grade fever. Numerous studies today are showing that people with depression often have low grade fevers (even when found to be medically healthy) which resolves after the depression is treated. Inflammatory markers that are measured in the blood (CRP) have been found to be elevated in people with depression. The higher these levels, the more treatment resistant depression becomes. Childhood trauma is associated with elevations in CRP into adulthood. Suicide attempters have been associated with elevated levels of inflammatory markers in the CSF of the brain with violent suicide attempters to have the highest levels. Anti-inflammatories have been associated with improving depressive symptoms.

d) Medical ailments: increased cortisol causes immuno-suppression leading to an increased chances of getting sick, get cancer, osteoperosis, weight gain , diabetes, stroke, dementia, and heart disease.

Depression is predicted to take over the number 2 cause of death in US, and its not because of suicide. It’s because simply being depressed without any other medical problems increases your risk of heart disease, diabetes, stroke, cancer and likely increases the chance to die from those complications. Seems quite similar to the side effects of cortisol.

9. The Freeze Response: Vagal tone is influenced by numerous factors including stress levels, nutrition, drugs/alcohol, the autonomic nervous system, posture (sitting vs standing), hormones, physical activity, and breathing. Additionally, the gut carries sensors that increase signal or reduce signal to the vagus nerve. Things that disrupt our digestion such as improper nutrients, food allergies, and inflammatory disorders can disrupt signal to the vagus nerve leading to lower tonicity and increased anxiety and indigestion.

Leave a Comment

Your email address will not be published. Required fields are marked *

If you think that I may be able to help you in your life and you’re on the fence, just get over yourself and contact me. I’ll do whatever I can to help you. 

Scroll to Top