The Human Stress Response Daniel M. Burrello From decades of research regarding organ specificity and the short term arousal system, we can gather that certain organs react to stress in specific ways (Danielson, 2002). There are several points common to stress related disease. Generalized stress arousal comes from our involvement with our experience of stressful situations and events. Upon presentation of these events the hypothalamus evaluates the level of response and arouses the defense system accordingly. Then, the appropriate systems are involved to address the stressor. The stress response sometimes lingers in the limbic system and cortex coloring one�s whole world as unpleasant and triggering avoidant reactions. When the problem is resolved, the trophotropic system attempts to gain homeostasis. However, the reticular activating system is likely to continue to be aroused and thereby cause an increase in reactivity in the central nervous system. Sometimes adaptation can increase the likelihood of resting nervous reactivity for the individual (Danielson, 2002). Sometimes the psychophisiological reaction can be prolonged (even if it is entirely inappropriate) and this causes the system to make choices as to which systems will come into play to fight this stress, leading to diseases of prolonged arousal. Harold G. Wolff (1962) has posited that stress is an internal reaction to external stimuli which is usually symbolic in nature. We cannot, obviously, use physical force against a psychological threat but sometimes, internal events and dialogue can cause the perceived threat to linger. Hans Selye (1953) was interested in sickened animals and saw that they had certain commonalities: they had an increased activity in the adrenal cortex, there was atrophy of the thymus gland and lymph nodes, and they exhibited gastrointestinal ulcers. He then formulated the general adaptation syndrome, which breaks down this process into phases: The alarm phase, the initial reaction to the stressor in which the pituitary gland releases ACTH or Adrenocorticotropic hormone, which, as its name implies, stimulates the adrenal cortex, this triggers the �fight or flight� response and there is generalized stress arousal. In the resistance phase, the arousal response is routed to the appropriate organ system. There is a decrease of ACTH but if the arousal is prolonged, organ fatigue and eventual malfunction can result. Adaptation to stress can become a disease in itself. The exhaustion phase marks the breakdown of the organ system involved with the response. There is another increase in ACTH and exhaustion, malfunction and or death can result. A muscular response to stress includes one�s approach-avoidant response. The proprioception from activated muscles can increase stimulation of the central nervous system. In addition, continuously tensed musculature can lead to other stress- related disorders. Further complaints can be pain cause by a lack of blood due to vessel constriction, joint pain due to recurrent flexion, tissue tears, and smooth muscle spasms. The muscles are controlled from the motor cortex carried via the pyramidial tract. Hypothalamic and limbic impulses move over the extrapyramidial tract and this can cause many unconscious movements such as increased involuntary muscle tension and a boost in voluntary bracing actions. Gastrointestinal responses, although not directly linked to the fight or flight reaction, is linked to survival motivations and hypothalamic pleasure/displeasure responses. One experiences several GI reactions to stress: The mouth dries up, spastic contractions make swallowing difficult, sometimes stomach pain and nausea is present during stress, and HCL excretions are affected by anger, fright or depression. In the intestines, peristalsis is also changed during an emotional event. Under stress, the cardiovascular system increases output in order to deliver oxygen to stimulated muscles. Blood moves more quickly and with greater force. Constriction of major arteries in a vascular response causes a rise in blood pressure. Blood is delivered with more speed to muscles. This decreases blood-flow to other areas of the body (like the digestive tract, the kidneys and skin). Vasopressin reabsorbs H2O into the circulatory system which keeps blood volume up to assure proper deliverance of oxygen and glucose to muscles. However, a continued stress response holds the cardiovascular system to this heightened operational state, which wears out the heart and stresses the arteries. Because of these systematic stress responses, stress is often a factor is many cardiovascular ailments such as hypertension, atherosclerosis (because stress arousal releases fats into the bloodstream) and vascular/migraine headaches due to vessel constriction in the brain. (Danielson, 2002) Like the octopus, we too have outward responses to stress. Though we don�t change shape, we can and do often change colors due to the stress response. The electric conductivity of the skin has a marked change during a stress event. This can be measured by testing the galvanic skin response. Temperature is changed by blood vessel constriction and dilation and several skin disorders such as, eczema, hives, psoriases and even acne, are commonly known to have associations with psychological response patterns (Danielson, 2002). The Immunes system�s response, because human life is so reliant upon the body�s defenses, has been a subject of a great amount of research. The individual immune system is classified in two categories: Innate immunities, such as the physical barriers of the skin and the acidity of the stomach as well as the white blood cells. Acquired immunities, such as antibodies which come from exposure to antigens; humoral defense or circulation antibody system, the process by which stem cells form into beta cells, which in turn are coded as plasma cells to become specific antibodies; and cell mediated immunity, which involve T-cells produced from stem cells through the thymus gland and into efficient killers of bodily invaders. Psychoneuroimmunologists have learned that neurotransmitters such as epinephrine and norepinephrine can attach to immune cells and reduce their function in destroying antigens. In addition, the immune system, in its constant dialogue with the control systems of the body can regulate the systematic immune responses such as how many antigen fighting cells are out there to do battle. So, one�s thoughts and mood can have a profound effect upon one�s ability to recover from an illness. This is seen to happen in one of three ways: The first is an under-response; involving the release of hormones from the adrenal cortex such as cortisone and aldosterone. The second is an overreaction causing ailments like asthma. The third is a misguided response such as the functions of an autoimmune disease in which the immune system attacks it�s (the body�s) own cells (Huskey, 1998). The effects of stress can be seen everywhere. In the best scenario, prolonged stress causes fatigue, which increase infections, minor skin conditions and colds. When that stress is prolonged and fatigue finds no respite, the immune system declines, disease becomes worse and the minor becomes major; skin conditions become serious, antibiotics must used for what were slight infections, and colds can become bronchitis and asthma. References Danielson, R.R. (2002) The body�s response to stress. [Chapter three of an on-line textbook. Posted on Web site Laurentian University.] Retrieved June 26, 2004, from the World Wide Web: http://danielson.laurentian.ca/drdnotes/4515ch03.htm Condrau, G. (1969) Psychosomatic nosology. Zeitschrift fuer Psychosomatische Medizin und Psychoanalyse, Vol. 15(2), Apr 1969. pp. 90-99. Database PsycINFO. Retrieved June 26, 2004 from the World Wide Web: http://search.epnet.com/direct.asp?an=1971-23473-001&db=psyh Huskey, R.J. (1998, December 4). Immune Response System [Article posted on the website University of Virginia.] Retrieved June 27, 2004, from the World Wide Web: http://wsrv.clas.virginia.edu/~rjh9u/imresp.html Selye, H. (1953) The general-adaptation-syndrome in its relationships to neurology, psychology, and psychopathology. Contributions toward medical psychology: theory and psychodiagnostic methods. [2 vols]. Weider, A. [ed]. xxv, 885 pp. 234-274. Oxford, England: Ronald Press. Wolff, H. G. (1962). A concept of disease in man. 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