ABSTRACT
The endocrine system is one of the major control systems of the body. Hormones, the blood-borne messengers of the endocrine system, help to regulate an array of important processes, including digestion, metabolism, growth, and reproduction. In addition, the endocrine system, in conjunction with the nervous and immune systems, plays a strong role in generating, intensifying, and extending physiological responses to psychologically meaningful stimuli. In this light, it is not surprising that the endocrine system has long been of interest to researchers examining biopsychological aspects of health and illness. Early investigators focused on the “stress hormones” epinephrine (Cannon, 1914) and cortisol (Selye, 1936, 1976); to a large extent, contemporary models continue to focus on the sympatho-adrenal-medullary (SAM) axis, which produces epinephrine, and the hypothalamic-pituitary-adrenal (HPA) axis, which produces cortisol. However, it is increasingly clear that many other secreted substances, including some produced by the immune system, may be involved in emotion and stress processes (e.g., Weiner, 1992). Moreover, stress is only one biopsychological process, and research has shown that other aspects of endocrine function are related to health.
