SOME MORE INSIGHTS ON STRESS AND DISEASE

*Author’s note: Information about stress and disease is changing daily. The most recent discovery that our emotions can either suppress or enhance the integrity of the immune system is now not only an intuitive assumption, but a scientific fact. This section will start with some basic information by the first leader in stress research, Hans Selye, and then move to the latest information about psychoneuroimmunology.

The General Adaptation Syndrome

Hans Selye, a young endocrinologist who created a name for himself as a leading researcher in this field, studied the fight or flight response regarding the physiological effects of chronic stress using rats as subjects. In experiments designed to stress these rats, Selye noted that several physiological adaptations occurred as a result of repeated exposures to stress: adaptations which had pathological repercussions. Examples of these stress-induced changes included the following:

1. Enlargement of the adrenal cortex, a gland that produces stress hormones.
2. Constant release of stress hormones; corticosteroids released from the adrenal cortex.
3. Atrophy or shrinkage of lymphatic glands (thymus gland, spleen and lymph nodes).
4. A significant decrease in the white blood cell count.
5. Bleeding ulcerations of the stomach and colon.
6. Death to the organism.

Many of these changes were very subtle and often went unnoticed until permanent damage had occurred. He referred to these collective changes as the General Adaptation Syndrome (GAS), a process in which the body tries to accommodate the stress by adapting to it. From his research, Selye identified three stages of this General Adaptation Syndrome.

Stage One: Alarm Reaction. The Alarm Reaction describes the original ‘fight or flight’ response. In this stage, several body systems are activated, primarily the nervous system and the endocrine system, followed by the cardiovascular, pulmonary, and musculoskeletal systems. Like a smoke alarm detector buzzing late at night, all senses are put on alert until the danger is over.

Stage Two: Stage of Resistance. In the resistance stage, the body tries to revert back to a state of physiological calmness or homeostasis by resisting the alarm. Because the perception of a threat still exists however, complete homeostasis is never reached. Instead the body stays activated or aroused, usually at a lesser intensity than the alarm stage, but enough to cause a higher metabolic rate of some organ tissue. One or more organs may in effect be working overtime and as a result enter the third and final stage.

Stage Three: Stage of Exhaustion: Exhaustion occurs when one (or more) organs that are targeted by specific metabolic processes can no longer meet the demands placed upon it and fails to function properly. This can result in death to the organ, and depending on which organ goes into dysfunction (e.g. the heart), quite possibly the termination of one’s life.

Selye’s General Adaptation Syndrome outlined the parameters of the physiological dangers of stress. His research opened the doors of understanding with respect to the strong relationship between stress and disease. In addition, his work laid the foundation for the utilization of relaxation techniques which have the ability to intercept the stress response, thereby decreasing the susceptibility to illness and disease. As is common with the standard medical practice of his day (and even today), initial stress management programs were geared to reduce or eliminate the symptoms of stress. Unfortunately, this approach has not always proved successful.

The Mind/Body Connection: Psychoneuroimmunology

Until recently it was thought that there was no direct link between the nervous system and the immune system. Because there was no evidence to suggest a neural link, virtually all physiologists believed that these two systems acted independently. Researchers have now isolated several neural endings connecting the central nervous system (CNS) to the thymus, lymph nodes, spleen, and bone marrow. In addition, the tonsils, adenoids, and Peyces cells of the small intestine have been found to be enervated by sympathetic nerve fibers. Even more astonishing is that a second and equally important link was discovered, indicating that messenger molecules produced in the brain are able to fit into the membrane receptor sites of lymphocytes like keys which fit into a door lock, thus altering their metabolic function. Research now indicates that not only are the nervous and immune system sophisticatedly linked, but that they actually communicate with each other. This communication system is altogether different from the efferent/afferent system observed between neuromuscular tissue and the brain. The codes of neuropeptide information are "spoken" through receptor cites of various lymphocyte cells located throughout the entire body, and their language is apparently influenced by emotional responses.

Candace Pert, former Chief of Brain Chemistry at the National Institute for Mental Health, made the discovery that immune cells have built in receptor cites for special types of messenger hormones classified as neuropeptides. In support of her work, similar findings have been replicated by Edwin Blalock . The identification of neuropeptides themselves is a rather recent discovery. In trying to uncover the mechanisms in the brain associated with chemical addictions and substance abuse, scientists were surprised to find that the brain actually produces its own type of endogenous opiates or neurotransmitters that have a similar effect to those manufactured externally and ingested into the body (e.g. morphine). The most publicized neuropeptide is the beta-endorphin. Currently, about 60 neuropeptides have been identified that are thought to be associated with mood change and immune regulation, including: the B-endorphin, interleukin, and interferon, to name but a few. Pert goes so far as to suggest that there may actually be one neuropeptide molecule which, like a chameleon, changes its configuration instantaneously by way of conscious (emotional) influence. Pert hypothesized that this spontaneous change may be accounted for by the wavelike oscillations or vibrations of the electrons in each neuropeptide molecule.

Because the hypothalamus was noted as having the greatest preponderance of these neuropeptide receptors, it was believed that these substances, produced by the brain, were involved with the biochemical mediation of emotional responses. Pert discovered however, that these neuropeptides are not solely produced by the brain. Her research revealed that throughout the body, immune cells not only have receptors for these neuropeptides, but in fact, they can manufacture them independently as well. Furthermore, immune cells seem to have a memory that enables them to adapt to specific emotional responses. These neuropeptides are believed to be the means of communication between the brain and T- and B-cells, making this a bi-directional pathway; immune cells speak to the brain, and vice versa. Pert’s discovery gave credence to the supposition that some emotions may actually suppress the function of these lymphocytes, while others may act as immunoenhancers.

There are several studies worth mentioning here, each contributing a small piece of evidence to the concepts of the stress response and emotional regulation, and their respective influences on the immune system. Although critics have taken some "pot shots" at the methodology used, these findings are still considered to be extremely relevant to the stress and disease phenomenon by leading PNI researchers.

A researcher named Jermott looked at the influence of academic stress on the rate of secretory immunoglobin (S-IgA) in Tufts University dental students. Subjects were administered a personality profile to distinguish a specific personality trait called power motivation (control) and from their results, were divided into two groups. In the course of the semester, saliva samples (used to measure S-IgA) were taken five times in the academic year. It was observed that mean SIgA values were significantly reduced during stressful periods, particularly in the students who demonstrated a strong desire to control. In a similar study, another researcher Kiecolt-Glaser and her colleagues reported a decreased proliferation of lymphocytes in Ohio State University medical students during their first day of medical exams, as compared with samples taken prior to and after the exam period. Perhaps because studies involving animal subjects are less likely to be considered tainted by human error or the placebo effect, similar studies investigating the relationship between emotional stress and immunosuppression have also been conducted using animals. In laboratory situations where rats were exposed to foot shocks that they could not control, a significant reduction in their immune function (decreased lymphocyte proliferation) was detected. In essence, it was reported that the behavior of these rats was a conditioned response to suppress their immune system. Conclusions were drawn that a helpless-hopeless attitude, developed by the inability to control factors in their environment, paves a path toward illness.

The concept of immunosuppression has also been observed with individuals who experience bereavement. Studies by Bartrop and colleagues indicated that bereaved spouses manifested lower lymphocyte proliferation within an eight week period of loss of a spouse. Similar findings were observed by a researcher named Schleifer who studied men whose wives died of breast cancer. Test results also showed a significant reduction in lymphocyte proliferation, leading some to suggest that humans can also be conditioned to suppress their immune systems by means of emotional thought processes.

One of the most interesting studies regarding the effects of relaxation and coping techniques on immunoenhancement was a follow-up study conducted by Kiecolt-Glaser in 1985. In this study, she and her colleagues investigated the effects of various stress management skills on Natural Killer (NK) cell activity among nursing home patients. Subjects were divided into three groups: those who were taught relaxation techniques, those who were provided with abundant social contact, and those who received no special stress management therapy at all. Results revealed that after a one month period, the NK count was significantly higher in those subjects who received stress management therapy than in the controls. Similar studies, inspired by the work of Norman Cousins, have also been conducted to determine the relationship between positive emotions and subsequent changes in the constituents of the immune system.

All these studies seem to indicate that there is a strong relationship between emotional responses and the biochemical changes they produce, specifically with regard to the constituents of the immune system. Whereas before Pert’s findings, it was believed that cortisol played the crucial role in immunosuppression, it is now thought that structural changes in neuropeptides, influenced by emotional thought, play the most significant role in immuno-incompetence. Currently, the search is underway for other neurotransmitters produced and secreted in the brain. Yet unknown, these may be responsible for producing the emotional thoughts which in turn, synthesize special neuropeptides that seem to influence the immune system so greatly. Pert is of the opinion that this type of search is fruitless. In a Noetic Science Review article published in 1987 she states, "I think it is possible now to conceive of mind and consciousness as an emanation of emotional information processing, and as such, mind and consciousness would appear to be independent from brain and body." It is this school of thought that has led her and others (e.g., Joan Borysenko, Larry Dossey, Deepak Chopra, and Bernie Siegel) to look beyond the physical body to the front door of the fields of parapsychology and metaphysics for answers which might explain the puzzling relationship between stress and disease.

Additional Recommended Reading

The Heart of Healing, by the Noetic Sciences Institute

Healing and The Mind, by Bill Moyers

The Healer Within by Steven Locke Love, Medicine and Miracles, by Bernie Siegel

Healing Words, by Larry Dossey

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