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http://www.abc.net.au/radionational/programs/allinthemind/science-of-mind-over-body-jo-marchant/7267100

 

A growing body of scientific evidence suggests our mental state can affect our physical body, but how can medical science ethically make use of the placebo effect? All in the Mind talks to journalist Jo Marchant about the science.

‘When there are claims of the mind having an effect on the body, often the alternative healers describe it as some kind of mysterious, magical healing power of the mind, and that turns a lot of scientists off. But I really don’t see it as mysterious or magical, it’s just biology.’

If your pain is eased after taking a fake pill, that’s occurring through exactly that same biological mechanism as you would get if you take a drug. You haven’t just imagined it, it’s really there.

JO MARCHANT

Science journalist Jo Marchant has pored over the growing body of scientific research investigating the brain’s ability to affect our physical health.

‘I think in science and medicine generally there is still this idea of the mind-body split, and that physical, measurable things are more valid for scientific study than subjective elements like thoughts and emotions and beliefs.’

According to Marchant, the brain and the body are far more intertwined, and treatments for physical maladies would benefit from a better understanding of the social and psychological elements of care.

‘What is really changing in the science of this is that researchers are discovering that taking a placebo can trigger measurable biological changes in the brain and the body that are very similar to those that are caused by drugs.’

What’s going on in the brain?

Research shows that if, for example, you respond to a fake painkiller there is a genuine release of endorphins in your brain.

‘If your pain is eased after taking a fake pill, that’s occurring through exactly that same biological mechanism as you would get if you take a drug. You haven’t just imagined it, it’s really there.’

Marchant says biological changes brought about by cognition correlate with our brain’s perception of a given situation and the warning signals it subsequently issues.

‘Things like pain, nausea, fatigue, they are there for a reason, they are warning signals, and are there to get us to change our behaviour. The brain all the time is deciding what level of those warning signals is necessary.

‘When there’s more danger, you need to take more urgent steps to do something about it. Whereas if you are feeling safe and supported, you’ve received medical treatment, the crisis is over. That’s telling the brain to ease off on the pain.’

When you receive medication that you believe is going to be effective, your belief feeds this same process.

‘It’s telling the brain the crisis is over, there’s no more need for that warning signal and the pain is eased.’

The power of the placebo

Marchant says the ability for the placebo effect to generate real biological change goes beyond the treatment of mild pain.

‘In Parkinson’s disease, for example, patients who respond to placebos get a flood of dopamine in the brain—this is the neurotransmitter they are lacking that is causing their symptoms.

‘With altitude sickness, researchers have found that you can give people fake oxygen and then you will see a reduction in [the] chemicals that are behind many of the symptoms of altitude sickness.’

The concept is surprisingly simple, but harnessing the power of the placebo into routine treatment has proven more complicated.

‘One of the problems with taking advantage of placebos has been the ethical concerns… the idea that it’s not ethical for doctors to lie to patients and tell them that they are getting an effective drug when really they are not.’

A new form of placebo, however, might provide a solution.

‘There are studies now in a few conditions—depression, irritable bowel syndrome, headaches, ADHD—suggesting that you can take a placebo and you know it’s a placebo and it still has an effect,’ says Marchant.

‘These so-called honest placebos are not necessarily as effective as real placebos … but they are significantly better than no treatment.’

Broadly speaking, Marchant believes taking an active drug is still the best option because it provides a proven ‘biochemical effect’.

‘But there are some conditions where drugs aren’t very effective or where there are significant downsides to drugs … some researchers suggest that maybe patients might want to try a course of honest placebos before moving on to a drug if they need to.’

Bedside manner and conditioning the brain

While pharmacological treatments remain critically important, Marchant says there’s cause to investigate and incorporate the benefits of the placebo effect into conventional medicine.

‘Studies suggest that expectation is a very important ingredient, for example. What you are told about a treatment and how it’s going to help you makes a big difference to how you are going to respond to it.’

Similarly, studies show social interaction with medical practitioners can influence how well patients respond to treatments.

‘Patients with conditions like irritable bowel syndrome or acid reflux disease do better if the practitioner is warm and empathic versus cold and polite … regardless of what treatment they are getting.

‘Or if the consultation is longer and involves lots of individualised questions, they do better than if it’s a short, standard consultation.’

Marchant says investing more research and funding into these aspects of care could enhance the efficacy of the drugs people take.

‘I think we should be treating social support, expectation, previous attitudes and experiences of patients … in a properly evidence-based way, just as we do when we are looking at the direct physical effects of drugs.’

Marchant was also intrigued by the process of conditioning the brain to heal the body using learned associations similar to those seen in classical conditioning shown in the well known Pavlov’s dogs experiments.

In her book, she notes the experience of Marette, an 11-year-old American girl in the 1980s who was diagnosed with Lupus disease.

During her chemotherapy, doctors designed a conditioning regime in which Marette was given a distinct stimulus—cod liver oil and rose perfume—alongside her regular drug dosage.

‘She got her drug alongside this strange mix… this very unfamiliar, distinctive mix of tastes and smells… And then they alternated.

‘So some months she got the chemotherapy alongside the rose and cod-liver oil, other months she only got the rose and cod-liver oil.’

The stimulus was so distinctive that when Marette was eventually given a placebo drug alongside the oil and perfume, her brain responded in a similar way to how it did when she received actual immunosuppressants.

This allowed doctors to halve the dose of drugs given to Marette over a one year period. As their 1993 study noted, Marette ‘improved clinically, and five years later continues to do well.’

The limits of mind/body treatments

While evidence for using our minds to help heal our bodies is palpable in some areas of health, placebos—and other mind-body treatments—are by no means miracle cures.

‘Researchers have said that for everyday conditions, [the placebo effect] is something that might help to reduce drug doses. I think for the more serious, life-threatening conditions, we are going to need a lot more research,’ says Marchant.

‘The mind can only work with the tools that the body naturally has available.

‘There are lots of ways in which the brain controls physiology and a lot of those can be modulated by our mental state. But what the mind can’t do is to replace something that the body is missing.

‘Somebody with diabetes who is missing insulin, for example: the mind is not going to suddenly magic up insulin that it was incapable of making.

‘Or in cystic fibrosis patients, they are missing a certain protein in the lung: the mind is not going to fix that.’

Despite its limitations, Marchant says the brain plays a significant role in how we experience symptoms, which in turn affects our quality of life.

‘The mind can influence things like the cardiovascular system, the immune system, the digestive system.

‘But we can’t just will these changes to occur—these things aren’t under conscious control.

‘By understanding when and how the brain is controlling these things, we can come up with clever ways to influence them through other means.’

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