Abstract
Animals and humans can be readily conditioned to associate a novel stimulus (often
a unique taste) by pairing it with the effects of a drug or other agent. When later
presented with the stimulus alone, their body's systems respond as if the drug or
agent were given. The earliest clinical applications demonstrated both conditioned
suppression and enhancement of immune processes. Unique benign stimuli, paired with
chemotherapy, come to elicit T-cell suppression when administered alone. The beneficial
immune responses to an antigen can be conditioned in the same manner. Further study
of what came to be called “psychoneuroimmunology” led to the understanding that the
familiar placebo effect, previously attributed to suggestion and expectation, is at
least equally dependent on the same sorts of behavioral conditioning. The demonstrated
ability to manipulate the immune system by a conditioned taste stimulus is, by definition,
a placebo: a therapeutic effect caused by an inactive agent. The purpose of this analysis
was to stimulate research in, and the application of, placebo–response conditioning
to emergency medicine. Clinical and experimental studies confirm the usefulness of
conditioned placebos in analgesia and in placebo-controlled dose reduction. Such conditioning
paradigms demonstrate “one-trial learning,” making them potentially useful in pain
and addiction management within a single emergency department encounter.
Keywords
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Article info
Publication history
Published online: May 22, 2020
Accepted:
April 8,
2020
Received in revised form:
March 26,
2020
Received:
December 22,
2019
Footnotes
The views expressed in this article are those of the author and do not necessarily reflect the official policy or position of the Department of the Navy, Department of Defense, or the United States Government.
The author is a volunteer with the United States Government. This work was prepared as part of his official duties. Title 17 U.S.C. 105 provides that “Copyright protection under this title is not available for any work of the United States Government.” Title 17 U.S.C. 101 defines a United States Government work as a work prepared by a military service member or employee of the United States Government as part of that person's official duties.
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