Lets learn what the steps are when the stress response is triggered described by Dr. Chestnut in his “The 14 Foundational Premises for the Scientific and Philosophical Validation of the Chiropractic Wellness Paradigm”.

1. First thing to occur is that your nervous system detects a stimulus (Tiger jumping out of a bush!)

2. Your nervous system sends the information to the cell bodies of the sympathetic nervous system where the stress response (fight or flight response) is initiated.

3. The sympathetic system directly influences visceral function via neuronal control of organs. All catabolic activities are increased (i.e. heart rate and blood pressure, etc) and all anabolic activities are decreased (sex glands, sex drive, digestion, growth (Growth Hormone production), cellular immunity. These responses are very intelligent as you don’t need a strong immune system, growth, or sex drive when you are running from a tiger. Those things are more important if you survive the tiger.

4. The sympathetic system send a message directly to your adrenal glands.

5. The adrenals produce catecholamines (adrenaline/noradrenaline - epinephrine/norepinephrine) and glucocorticoid (cortisol) into the blood stream.

6. Catecholamines act on the heart to increase cardiac output. This along with vasoconstriction from sympathetic system output, serves to increase blood pressure, which allows rapid delivery of stress response hormones and energy substrates.

7. Catecholamines stimulate the amygdala in the brain so that emotional/anxiety memories dominate during stress (so we remember to look for the tiger next time we are at the watering hole).

8. Catecholamines inhibit factual learning, working memory and the ability to focus attention at hippocampus. (You don’t need to be able to learn reading or math when your running away from the tiger.)

9. Amygdala releases CRH which activates centers in the brain that acts on emotional centers and learning centers in the brain. (Areas for logical behavior and short term memory are inhibited; centers for emotional learning and instinctual behavior are simulated). this again is innately intelligent as it allows for best chance to survive the fight or flight.

10. Release of noradrenaline during during stress response causes an increased sensitivity of the sensory systems (improves chances of survival during fight/flight). However, this means our concentration is easily distracted and that pathways such as those for nociception become sensitized and exert greater effects. “Stress sharpens the signal detection system at the cost of concentration.” (Michael Meaney Ph.D.) The stressed person becomes easily distracted.

11. Studies show that chronic stress can lead to chronic changes in cognition - cells in the hippocampus actually shrink!! Interestingly, research also shows that chronic movement stimulation/exercise (proprioception via cerebellum) results in an increased in the size of hippocampal cells!!

This list is almost a copy and past from Dr. Chestnut’s work as I don’t think I could have written it any better.