Optimists may feel less Pain because they believe Painkillers Work BetterIf your Expectations are positive then the Effectiveness of Pain Relievers is IncreasedHave you ever left the doctor’s surgery not feeling very positive about what has been prescribed and then finding out that the medicine didn’t work as well as hoped? Well a new study just published in the medical journal Science Translational Medicine may shed some light on what actually happened.
The study found that with pain medications the effectiveness depends upon the view of the patient. If they are positive then the medication works better than if they are negative about the treatment. Your expectations have an effect on your chances of getting better quicker.
The new study took a novel approach by including brain imaging techniques as a tool to examine the areas of the brain connected to pain. This addressed the view from scientists that earlier research did not look deeply enough at the brain’s mechanism related to the power which someone’s expectations might have on the efficiency of any particular drug.
Expectations can vary the Effectiveness of Drugs
The researchers, from the U.K. and Germany carried out the research on 22 healthy volunteers, so the study was small scale. It took the form of inflicting pain on the volunteers by use of a heat source whilst monitoring their brains and giving medication to reduce pain. The aim was to find how the patient’s who were optimistic compared to the pessimists when looking at their expectations relating to pain relief medication.
The researchers found that those who expected the pain medication to work had twice the pain killing effect than the participants who were less positive about the drug’s power.
The drug, called Ultiva, is routinely used in surgery, and was administered intravenously to the volunteers.
The findings have led Irene Tracey, of Oxford University’s Center for Functional Magnetic Resonance Imaging of the Brain, to say, “Doctors shouldn’t underestimate the significant influence that patients’ negative expectations can have on outcome”.
The study was structured so that the 22 participants were given the medicine intravenously and then positioned in a MRI scanner. Once in the MRI scanner heat was applied to a leg until the volunteer rated the pain at 70 on a scale from 0 to 100.
The researchers then varied the amount of the drug they administered without telling the participant. This meant that the patient had no anticipation or thought about the treatment. It was found that from an average pain rating at the commencement of the test of 66, the rating dropped to 55.
The volunteers were then informed that the drug would be administered, but the researchers did not vary the amount being given. The ratings for pain continued to drop until they reached an average of 39.
The researchers then warned the volunteers that they were about to cease administering the pain killing drug and the pain may increase, but they kept the dosage at the same level. The volunteers’ opinion of the pain was that it increased, they rated the pain at 64, yet the amount of the pain killing drug being administered had not varied.
The brain scans on the MRI showed that the participant’s brain’s responded to pain but were influenced by the expectations of the individual. This has led Tracey to say, “Clinicians need to be aware of the power of expectations on any type of treatment”.
Areas of the Brain with Increased Activity
The areas of the brain seen to have responses and activity because of the expectation of more pain include the hippocampus, medial prefrontal cortex and the mid-cingulate cortex. The researchers say that these are the areas that affect anxiety and mood.
And when the volunteers expected the pain to be reduced it was noticed that the anterior cingulate cortex had increased activity. This area is thought to be associated with reward anticipation and rational cognitive functions. The striatum also increased its activity, this area has influence on balance and movement.
The researchers believe that their work has identified that within individuals there is a, “large inter-individual variability in response to placebo treatment”. They also go on to say that ‘placebo effectiveness’ can now be integrated into everyday medicine. The study leads the way to the next phase of research investigating the association between disease, personality, drugs and curative circumstances.