-relation between stress and health outcomes. Up until the early 1980's, it was generally acknowledged by the then dominant scientific paradigm that the immune system was an auto-regulating one, working with minimal input from the central nervous system (CNS). Robert Ader (1983, p. 251) established that "the immune system is integrated with other physiological systems, and thus sensitive to regulation or modification by the brain" (cited Rice, 1999). Pinel (1993) elaborated on Ader's research showing that "as psychosocial stressors occur, neural cascade beings, a process which involves the hypothalamic-pituitary-adrenal (HPA) complex" (cited Rice, 1999). The corticotrophin-releasing factor (CRF) hormone is released by the hypothalamus, which in turn causes the anterior pituitary gland to release a hormone named adrenocorticotrophic (ACTH). This stimulates the adrenal cortex to secrete steroid hormones called glucocorticoids (Pinel, 1993, cited Rice, 1999; Kiecolt-Glaser et als., 1992). The primary purpose of this response is to contain (short term) the stress reaction, and in so doing avert damage to itself. However, in response to higher-level stressors, glucocorticoids negatively impact, resulting in suppression of the immune system (Rice, 1999; Brosschot, Benschop, Godaert, Olff, DeSmart, Hgeiinen and Ballieux, 1994). Thus the likelihood of resulting illness is increased, due to the immune system being weakened. Ader's findings also provided researchers with credible and convincing evidence in relation to the influence of conditioning on the immune function, and the relationship between psychosocial factors, (such as life stress) and immunocompetence. (Rice, 1999). Immunocompetence, as described by Rice, is the "degree to which the immune system is active and effective" (1999, p. 142). Studies by Manuck, Cohen, Rabin, Muldoon and Bachen (1991) showed that: Psychological stressors induced cell division among CD8 cells, thereby inc...
