05 May 2014

Letter to D re: placebo

d:

The mention of Cousins was was made in the context of a general discussion how the mindset can alter one's physiological state. For Cousins, the Marx Brothers' movies (and other comedy movies and shows) changed his mindset in a way that allowed previously "locked up" healing mechanisms (endorphin generation, etc.) to go to work.

Cousins said of placebos in 1979, “The process works not because of any magic in the tablet, but because the human body is its own best apothecary and because the most successful prescriptions are filled by the body itself.”

One early researcher into the placebo effect -- mindset triggers, I guess you could call them -- was Harvard-educated American surgeon Henry Beecher during WWII.  He ran out of morphine in a combat situation, and, in desperation, gave a injection of saline.  It worked.  The soldier calmed down,and  the surgery was performed. with  the soldier feeling little pain.  Running out of morphine was common in WWII, so he used this technique many times with similar results.

Because of this experience, in 1955, Beecher authored a clinical review of 15 studies published in JAMA. It discussed the significance of placebos, and called for a new model of medical research that would randomly assign subjects to receive active medications or placebos— now referred to as randomized, controlled trials— so that this placebo effect wouldn’t distort results.

H. K. Beecher, “The Powerful Placebo,” Journal of the American Medical Association, vol. 159, no. 17: pp. 1602– 1606 (1955).


From what I've been reading, placebos work not because "it's all in your mind," but because the mindset has significant say over what healing mechanisms are activated in the body and the brain. Thus, it's all in your mind -- and your physiology.

Different mechanisms for the mindset acting on physiology have been explored in the laboratory.

One placebo mechanism:
Classical conditioning of neurons 


One mechanism involved in the placebo effect is classical conditioning. (Recall Pavlov's dogs: A dog would be given food and would salivate while a bell was rung.  After enough repetitions, simply ringing the bell without providing food would cause the dog to salivate.)

This classical conditioning process has been shown in the laboratory to be at work on the level of brain neurons with the placebo effect.
“Expectation and Dopamine Release: Mechanism of the Placebo Effect in Parkinson’s Disease,” Science, vol. 293, no. 5532: pp. 1164– 1166 (2001). R. de la Fuente-Fernández, T. J. Ruth, V. Sossi, et al.
“Placebo-Responsive Parkinson Patients Show Decreased Activity in Single Neurons of the Subthalamic Nucleus,” Nature Neuroscience, vol. 7, no. 6: 587– 588 (2004)
Another placebo mechanism:
Epigenetics
I have to get to work, so the upshot is this:  The epigenome dynamically responds to the environment. Stress, diet, behavior, toxins, and other factors regulate gene expression. Epigenetic expression can be affected by the placebo effect.

Click here for a user-friendly tutorial on epigenetics

All of this fascinates me, especially the idea that one can make one's own placebo effects.

Oeming

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