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KRISTIN D. HUDACEK
One of the ways that stress changes the immune system is through
the sympathetic nervous system. Sympathetic fibers directly connect
the brain to primary (bone marrow and thymus) and secondary
(spleen and lymph node) lymphoid tissues via descending fibers.
When stress creates a negative emotional state, the biochemical state of
the brain influences sympathetic nerves and their release of neu-
rotransmitters, which directly communicate with the immune system.
In addition, hormones play a role in the interaction of stress and
immune functioning. Stress activates the hypothalamic-pituitary-
adrenal axis, sympathetic adrenal-medullary axis, and hypothalamic-
pituitary-gonadal axis, all of which produce hormones that can bind
leukocytes and dysregulate the immune system (Miller & Cohen,
2001). In particular, stress increases the pituitary release of adrenocor-
ticotropic hormone (ACTH), which subsequently elevates serum corti-
sol levels. Both ACTH and cortisol can act on the immune system.
Finally, stress increases the neuropeptide
β
-endorphin, which increases
NK cell activity since 75% NK cells have a receptor for
β
-endorphin
(Bakke et al., 2002).
For a psychological therapy to intervene in the stress response and
successfully modulate the immune system, Miller and Cohen (2001)
have proposed that three conditions be met. First, a patient must be
exposed to an immune-dysregulating stressful event to have immune
impairment. According to Kiecolt-Glaser and Glaser (1992), this condi-
tion is necessary because homeostatic mechanisms prevent a normal
immune system from responding to intervention and becoming overe-
active. Breast cancer patients fulfill this requirement since they are psy-
chologically traumatized by their diagnosis and physically challenged
by their invasive neoplasia and taxing treatment. In fact, as early as 200
A.D., the Greek physician Galen related depression to the develop-
ment of breast cancer (Simonton & Matthews-Simonton, 1981). Second,
the intervention must be designed to reduce stress. Hypnosis clearly
fulfills this obligation since its purpose is to alter the cognitive percep-
tion of stressful events. Physiologically, hypnosis has been shown to
have a calming effect on the body by decreasing heart rate and blood
pressure (Bongartz, Lyncker, & Kossman, 1987).
Finally, the third condition that must be met in order to alter
immune function psychologically is that the intervention must be able
to modulate immune processes dysregulated by stress. Research has
shown that the physiological effects of stress include decreased levels
of total T cells, CD4
+
(helper) T cells, CD8
+
(cytotoxic) T cells, B cells,
NK cells, interferon-gamma (IFN-
γ
), and sIgA; increased levels of
interleukin-2 (IL-2); and downregulation of NK cell cytotoxicity and
lymphocyte proliferative responses to mitogens such as concanavalin
A (ConA) (Herbert & Cohen, 1993). The ability of hypnosis to reverse
such immunological effects of stress is under investigation. More than
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