A look at the stress response
Our response to stress dates back millions of years as our ancestors responded to the environmental factors to survive. And with only the options of hunting for food or becoming the food of predators and wild animals. The continuation of the stress response including the flow of adrenaline through the bloodstream was important for the survival and existence of humanity. In a more civilized society, our stress response is needed during dangerous situations to keep us safe, or perhaps during the super bowl. But for combat veterans exposed to the dangers of war, and the numerous redeployments to war zones; which I totally understand is necessary if we are to defeat the war on terrorism does not allow our warriors to “turn off the stress button” here on the home front. Adrenaline is responsible for the response that prepares the body for fighting or fleeing dangerous situations. During this automatic response, internal physical changes are increased heart rate, and increased blood pressure to increase muscle strength, and endurance, increased sweat to keep the body cool and free from exhaustion during the fight for survival. Other physical changes will be discussed during the training phase of our program. Too much adrenaline (stress) and resulting surges in blood pressure can damage the blood vessels of the heart and brain creating rough spots known as “lesions” where sticky plaque build up and restrict blood flow causing heart attack and stroke. In a continuous stress response, the hormone cortisol becomes overactive, and continues to flood the body even after the emergency has passed leading to what, Dr. Bruce McEwen author of, The End Of Stress As We Know It, describes as allostasis or overload. This creates an imbalance suppressing the immune system as in the case of people who are chronically stressed are susceptible to colds and other types of infections.
Dr. McEwen explains: Cortisol acting in the brain and adrenaline acting outside the brain aid us throughout the day forming chemical links with brain cells in ways that affix important things in our memories. People with PTSD, severe depression, and anxiety have high cortisol levels around the clock mainly during the evening. Combat stress and stress in general causes moderate levels of cortisol secretion causing abnormal abdominal fat, loss of muscle mass, and bone mineral loss. Memory loss and other cognitive problems are results of cortisol overload. This is in association with two key areas of the brain’s limbic system (covered during our training) responsible for reaction and memory, the amygdala and hippocampus. Cortisol secretion in this area causes atrophy and permanent brain damage.
Dr. McEwen helps us clarifies the urgencies of our program and its mission, he describes a saga known as the Grisnismal: The Norse god Odin had two ravens that flew over the world and brought him news at the end of each day, there names were thought and memory. Ordin voices concern over what I feel should be the concern of our nation as it relates to our war heroes: I fear thought, lest he come not back But I fear yet more for memory.
Dr. Joseph LeDoux explains the limbic system and stress: The amygdale is critically involved in control of the release of adrenal steroids. When the amaygdala detects danger (12 millisecond response time) it sends messages to the hypothalamus, which in turn sends messages to the pituitary gland releasing adrenocorticoltropic hormone ACTH flowing through the adrenal gland to cause the release of steroid hormone. In addition to reaching target sights in the body, the steroid hormone flows through the blood to the brain where it binds to receptors in the hippocampus, amygdala, prefrontal cortex, and other regions. Because the adrenal and pituitary gland secretions are reliably elicited by stressful events, they are called stress hormones.