»» The reproductive system shuts down. »» Muscles become tense, especially the back, neck, jaw, and shoulders. »» The immune system suffers more inflammation, clotting, and allergic
reactions (over time, causing poor immunity against infections or cancers).
»» The cardiovascular system experiences an increase in heart rate and blood pressure.
»» The respiratory system experiences an increase in breathing rate and inflammation.
»» The metabolic system shifts to catabolism, or breakdown. The liver releases glucose stores. Fats are broken down to fatty acids. Proteins from muscle stores are broken down into amino acids. Bones are broken down for minerals.
»» The brain experiences less complex thinking, and more fear-related behaviors are initiated, causing hyper-alertness and arousal.
»» Your mood is affected by a loss of serotonin, and other neurotransmitters cause depression, anxiety, and other mood disorders.
»» In your mind, higher-thinking centers are shut down, as are big-picture
thinking and judgment to enable focus (causing more myopic thinking).
The feedback loop Once out of danger, the built-in turn of the switch in your brain turns off the stress response. Stress hormone levels drop, your heart rate, blood pressure, and breathing slow down, your muscles relax, your digestive system starts working, and blood flow resumes to your fingers and toes, as the parasympathetic nervous system (the one that creates calm) is activated, and the sympathetic nervous system (the one that creates hyperalertness and hyperactivity) is turned down. Happy chemicals, like dopamine and morphine-like substances, fill your brain as adrenalin levels wear off, giving you the feeling of euphoria and calm. This is considered a positive feedback loop, or when the message is received by the brain that the outcome is positive (stress gone), so it turns off the stress response switch. Here’s an example, which shows how you go from hangry (the combination of hungry and angry) to happy:
1. 2. 3. 24
Your blood sugar drops. The body picks up the imbalance and sends an alert to the brain. The stress response is activated, stress hormones are released, the heart rate increases, and the intestines contract.
PART 1 Getting Started with Resilience
