Hormones and Stress

The fight-or-flight response is a hormonally controlled situation in which
the body must pool all of its available resources within a relatively short time
span. The detection of danger by any of the special senses (sight, smell, hearing) triggers the hypothalamus to activate the pituitary gland to release
adrenocorticotropic hormone, which causes the adrenal gland to release its
highly motivating hormones and neurotransmitters. Many body systems are
subsequently affected, especially the heart and circulatory system, the central
nervous system, the digestive system, and even the immune system. One
reason the fight-or-flight response is of major interest to psychologists is its
link to stress.
Stress is overexcitation of the nervous and endocrine systems. It is caused
by the body’s repeated exposure to danger, excessive physical exertion, or
environmental pressures that affect the individual psychologically. Stress is a
major problem for humans in a fast-paced technological society. The physiological
and behavioral manifestations of stress are very evident. There is considerable
evidence that stress is associated with heart disease, cancer, weakened
immune systems, asthma, allergies, accelerated aging, susceptibility to
infections, learning disorders, behavioral abnormalities, insanity, and violent
crime.
The demands that are placed upon individuals in fast-paced, overpopulated
societies are so great that many people exhibit a near-continuous fightor-
flight response. This response, in which the body prepares for maximum
physical exertion in a short time span, is the physiological basis of stress. It is
not intended to be maintained for long periods of time; if it is not relieved,
irreparable effects begin to accumulate throughout the body, particularly
within the nervous system. Medical psychologists seek to understand the hormonal
basis of physiological stress in order to treat stress-prone individuals. 398