Placebo effect was known since the dawn of civilizations but only recently the neuroscience discovered that this phenomenon is the essence of the deepest secrets of mind-body “programming” for health, disorder and even death.
In the May issue of Psychiatric Times, neurobiologist Dr. Medina summarized eloquently the neurobiology of placebo effect and how this phenomenon related to illness. He said that new exciting findings were pointing to the brain mechanisms by which “mind-based” expectations influence “body-based” physiologies and pathologies.
Many researchers treated placebo as annoying statistical nuisance and an odd statistical quirk not worth paying attention to but now placebo is being taken seriously. In a landmark study in 1979, one group performed a rigorous study of placebo analgesia (the ability of sugar pill to mimic the analgetic effect of pain relievers). What they found is that placebo phenomenon not only was a true fact, but they also established a neuroscientific basis for it.
This study was replicated many times. One of the most fascinating findings was that one could experimentally increase or decrease the analgetic effect of placebo at will. A strong correlation was found between what was expected from a pill (called treatment expectation) and from descriptions of how great this particular pain medication was: the greater the expectations, the greater the observed placebo analgetic effect.
The placebo effect is based on the physiology of expectation.
Expectations have a very significant role in almost all emotional processes of the brain.
As all of us know the more emotionally important is the stimulus, the more attention it triggers. This is directly related to survival, more exactly to a threat to survival. Those who do it quicker, live longer. Many scientists believe that the primary job of emotional responses is to serve as kind “reminder” about the dangerous stimulus, so we are continuously attending to it.
Expectation of danger is a timing issue. It is the ability to react to an event that hasn’t happened yet. This is a very useful evolutionary trait – nothing could be faster than the reaction to an event that has not yet occurred! Many brain networks are devoted exclusively to the expectation responses.
Placebo effect is a special case of functional anatomy and related to the brain reward processing system. Specific areas of the brain (for doctors: the ventral tegmental area of the brain is a specific reward network that connects the amigdala, ventral striatum, orbitofrontal cortex, and rostral anterior cingulate cortex (rACC) via dopaminergic projections). The important conclusion is that dopamine made the EXPECTATION of trouble to be turned into changes in the body that are actually making REAL troubles.
To make it simple and clear – if you REALLY EXPECT the problems to happen – you might get it!
How our brain decides what will be dangerous? One system is related to processing of threatening visual stimuli. Such stimuli go to amigdala and extrastriate complex that have the so-called top-down modulations through the limbic regions. (This region decides how strong emotions are needed.) Involvement of dopamine connections in placebo effect was also confirmed by investigators that did not study placebo but investigated addictive behaviors. One phase of the expectation cycle is called the anticipation phase. It was shown that this anticipation phase related to dopamine activation of a network.
It was found later that placebo was seen not only with pain medications and not even specifically with medications. Placebo response may apply to ANY emotional experience and belong to a strange land between mind and body in norm and illnesses.
In one careful study it was found that subjects had a pleasant experience even if they have been given very unpleasant stimuli but told that it was important for health.
These subjects were simply expected benefits accepting “no pain – no gain” logic.
The new data about the neurobiology of placebo effect confirmed that we could program our health or make ourselves sick by the expectations in your mind (strong beliefs) to actual changes in body physiology – for good or bad.
When the patient anxiously reads possible side effects of medications and gets them all it is an example of the “reversed” placebo. Another example of bad expectations produces the so-called “Anniversary Phenomenon,” when the person expects to die at the certain birthday as his father did; or spouses who die shortly after death of the loved one.
How to “re-program” yourself from being sick to being healthy is a complicated issue which we will discuss in the next issues.
Ref: John Medina, Placebos and Psychosomatic Illness.
Psychiatric Times, May 2006:17 -20