Negative changes occur in the immune system as a result of stress
, hostility, and resentment. Emotional responses to stressors can suppress the immune system within minutes, and effects will last for hours. During the time that the immune system is not functioning, the body is vulnerable to infection and illness.
A bi-directional communication pathway exists between the brain, body, and immune system. Biochemicals (e.g., hormones, neurochemicals, peptides, endorphins, cytokines) carry messages from brain to immune system, and from immune system to brain. A complex interaction between the stressor and the person's physical, mental, emotional, and spiritual responses to the stressor is mediated by memory (past experience), thoughts, and beliefs. The mind/brain, not the actual event, decides the meaning of the stressor and how to respond to it. This occurs first, and if the stressor is perceived to be negative, then the stress mechanism is activated. The internal response is dependent on beliefs and memories. Fear and apprehension activate the stress mechanism. When the stress response is initiated, neurochemicals (i.e.,epinephrine and glucocorticoids) are released, and the immune system is inhibited during that time. If the stressor is perceived to be positive, different emotions arise, and the immune system is affected in a different way. The immune system is turned on and off depending on these variables. If mind/brain messages are mixed, immune response is also mixed.
Several systems are involved in the stress response.
- Nervous system, including brain, memories, past experiences, beliefs, and future projections.
- Neurochemical system, including neurohormones, neurotransmitters, neuropeptides, endorphins, neuroreceptors.
- Hormonal/endocrine system, mainly corticosteroids.
- Immune, repair, and healing systems, including stress mechanism and defensive systems.
- Nutrition and body chemistry. Deficiencies in these areas, such as inadequate nutrition, illness, chemical imbalances, affect the stress mechanism at all levels.
- Feedback from body tissues, cells, and organs (e.g., cytokines, lymphokines).
The immune system cells have receptors in the body that hear signals and allow the nervous, endocrine, and immune system to communicate with each other and with the rest of the body.