Stress and Your Nerve System
Ultimately, it is your nerve system that is responsible for handling stress. Stress comes from three categories of sources: chemical, physical, and mental. That is, stress results from unhealthy choices in how you eat, how you move and how you think. Once your body encounters stress, however, there is a common response from your body.
The physiologist Hans Selye was the first to coin the term "stress" just over 50 years ago. The hallmark of the response to stress inside your body (the stress response) is the release of stress hormones. As discussed below, the release of these hormones is controlled by your nerve system. When your body perceives something as stress, it sends signals to release hormones. These signals are controlled by a part of the nerve system called the sympathetic nervous system. Adrenalin and noradrenaline, also known as epinephrine and norepinephrine, along with cortisol are the initiators of a system-wide stress response in your body.
Fight-or-Flight, Rest and Repair, and Your Nerve System
Just like being awake and being asleep are two separate and distinct states, being stressed and being in a state of healing and repair are two separate and distinct states. When our bodies are in a state of stress, the hormonal release stimulated by the nerve system prepares the body for a state of activity. This means tearing tissue down, preparing to burn energy, and preparing to move. Blood is sent to muscles away from organs, blood pressure rises as vessels tighten, digestion slows, and immune responses weaken as the body prepares for action. This feeling of stress, often referred to as the fight-or-flight response, is directed by the sympathetic nervous system.
The sympathetic nerve system is used by your body in response to stress, or, in other words, anything that your body perceives as a threat. Acting intelligently, your body’s response to threats is to prepare for action: fight-or-flight. Even thinking of a stressful event, taking the time to do so now, you will be experiencing the influence of the sympathetic nerve system in your body.
To do this, however, there is a cost. Spending energy to deal with a threat means halting the activities of rest and repair. The sympathetic nerve system activity has an opposite system in your body dedicated to rest and repair called the parasympathetic nerve system.
Your parasympathetic nervous system is responsible for the activity of digestion, relaxation and reproduction. This is the system your body activates during times of safety for healing, tissue repair and procreation. In order to heal and repair effectively, you want to be in a state of rest and repair.
Recent research over the past twenty five years has shown how far-reaching the influence your nerve system has on the function of two other ‘”super-systems” inside your body: your immune system and your endocrine, or hormonal, system.
The Hard-Wired Connection Between Your Hormones, Immune System, and Your Nerve System
Prior to about twenty five years ago, mainstream science did not understand the intimate connection between the immune and nerve systems. Patients of chiropractors, however, reaped the benefits of improved nerve system function for decades before this. There is an example of life-saving results that patients of chiropractors (doctors trained to remove interference to nerve system function) had during the flu pandemic of 1918. (Link...)
In fact, every immune organ in your body is richly influenced by communication from your nerve system. Immune organs located in your body, including your network of lymph nodes, your thymus, spleen and bone marrow, and also most importantly in your digestive system, have their activity directed by your nerve system.
This connection is also one of the underlying mechanisms why you are more susceptible to becoming sick when you are stressed. During a period of stress, you shift into a more sympathetic fight-or-flight mode, promoting the release of stress hormones. Chronic stress hormone release makes you more susceptible to illness.
Today, research showing how the immune system, hormonal system and nerve system are hard-wired together continues to grow more and more. To read more, check out these links on this growing field of psychoneuroimmunology:
- Dr. Ader and the origins of psychoneurobiology (Link...)
- Textbook of Medical Physiology. Guyton and Hall, Tenth Edition. Pages 678-679
- Textbook of Medical Physiology. Guyton and Hall, Tenth Edition. Pages 678-679
