Our life brings us different things every day and, as a result, we respond to them emotionally and physiologically. At some point, everybody feels stressed. Stress is a normal physiological and psychological reaction to a threat. Natural selection throughout our evolution favored it because its only purpose is promoting our survival. Thus, whether it is a physical threat (a car crash ) or psychological ( a deadline or an argument with someone), the response to stress kicks in to help us deal with the situation.
The Chain of Reactions
Stress response involves a complex interaction of many body systems, mainly to make our body work more effectively and to minimize all unnecessary functions. It is as if our body switches on a survival mode, where all the energy and services are directed toward fighting a threat.
It is achieved via Autonomic Nervous System (ANS) of our body, which creates a nonconscious automatic response, preparing our body to fight and survive. The hypothalamus region controls the response in our brain, which initiates the release of corticosteroid hormones from the adrenal glands into our bloodstream ( epinephrine, norepinephrine, and cortisol). The chain is followed by:
- Increased activity in the Central Nervous System (CNS) and, therefore, mental activity
- Increase in our Heart Rate -à increase of Cardiac Output à Increased Blood Pressure
- Dilation of airways and increased inhalation ( delivering O2 to the brain and muscle via blood circulation)
- The reactions above promote faster metabolism and blood flow to limbs and muscles (increasing contraction ability). The response is supported by the release of glucose and fatty acids.
- Dilation of pupils ( allowing light, to sharpen eyesight)
- Regulation of the body temperature and composition via sweat glands
In other words – you are ready to run or fight.
Although, as it has been mentioned earlier, the work of other body systems temporarily minimized, which includes :
- Reproduction System
- Immune System
- Digestive system
- Decreased functioning of Intestinal Tract and Kidneys
As a result, we achieve a state effective for survival – speed, alertness, strength, emotional sharpness. This response happens automatically in seconds. Usually, when the stressor disappears, the reaction is soon brought down by the Parasympathetic Nervous System (PNS), which returns things back to normal. When the stressor persists for a longer time or reappears consistently, the human body enters a state of chronic stress. As much as effectively our body responses to stress, it’s regulated performance during prolonged stressful condition starts overloading and failing, eventually leading to different health problems.
Don’t get me wrong- speeding is fun, but what happens to your car if you “push” it for hours?
Different Responses to Stress
According to mental health expert Connie Lillas, a functional explanation exists to establish the three traditional means of how people react to stress:
- Foot on the gas – An angry agitated stress response
- Foot on the brake – A withdrawn or depressed stress response
- Foot on both – A tense and frozen stress response
The response to stress depends on a variety of factors, such as person’s sex, age, mental state ( emotional control and attitude), physiological state. Therefore, what is stressful to one person might not be stressful for another.
According to Dr. Harbuz (Bristol University): “a single exposure to a particular stressor can reduce the response to that same stimulus several weeks later.” It suggests that our body can adapt to specific stressors through repeated exposures, on the condition that regulatory systems work well, although, it is not always the case.
When our systems do not cope, a long-term exposure to stress leads to major changes of neurotransmitters in the brain, excess of corticosteroids in the blood and other neuroendocrine changes. These changes are associated with the occurrence of depression, rheumatoid arthritis, the risk of heart strokes, sleep problems, skin conditions, etc. Thus, when the balanced state (homeostasis) is not achieved you are fighting not only against stress but against yourself.
As I said before, everybody gets stressed at some point. And though, due to evolution, we are prepared to fight, sometimes we have to know how to take control and manage stress for our well being. Driving a car when you know how is safer.