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  • A placebo is a treatment with zero therapeutic value but magical healing

  • power. Common placebos include sugar pills inert saline injections, other

  • procedures and surgeries that are completely fake. Placebos are especially

  • effective to treat pain, chronic stress related diseases, like insomnia, and forms

  • of depression. What most don't realize is that while placebos are fake the placebo

  • effect does it's magic even if you get real treatments from a normal doctor.

  • Placebos tend to follow one simple rule: the more ritualized and extreme the fake

  • treatment the more effective their effect. In short, sugar pills work well,

  • sham surgery works wonders. Since standard doctor appointments are often

  • highly ritualized the placebo effect is part of the cure we think we receive. To

  • understand this better let's look at Mr. and Mrs. Martin who both suffer chronic

  • back pain. Mr. Martin feels the pain first and he decides to go see a doctor

  • who diagnoses osteoporosis and treats him with physiotherapy. After a few days

  • of treatment, Mr. Martin feels better. He starts to track the progress of his pain.

  • He soon learns that he always goes to the doctor on the days when the pain is

  • the worst and always feels better soon after. He becomes a big advocate for

  • physiotherapy and recommends it to his wife and she joins him. But do we really

  • know that the therapy works? Despite months of therapy things get worse for

  • both Mr. and Mrs. Martin. Together they go to the hospital where Mr. Martin's

  • doctor prescribes painkillers. Mrs. Martin decides to get a second opinion.

  • Her new doctor has recently learned that for some chronic pain placebos work

  • equally well. Instead of giving Mrs. Martin painkillers

  • the doctor prescribes simple sugar pills though he tells Mrs. Martin that they

  • are pain killers. The next day they both feel much better.

  • Mr. Martin notices that he has no problem sawing wood and Mrs. Martin can

  • easily put on her shoes. She can confirm that the painkillers work but do they

  • really? Unfortunately, it doesn't take long before the pain comes back and they

  • return to the hospital. Mr. Martin is now treated with

  • vertebroplasty, a popular treatment offered to people who suffer from back

  • pain due to osteoporosis. To administer it the doctors inject cement directly

  • into his vertebrae, the bones that form the spinal column. Mrs. Martin's doctor

  • simply has her smell a container full of cement and then administers a saline

  • injection, which does nothing. Her doctor learned about this placebo

  • from research published in the U.S. National Library of Medicine. It showed

  • that a large randomized controlled trial found no benefit of vertebroplasty over

  • a sham procedure. Right after the surgery the Martin's meet in the lobby and share

  • their experience of the process: both feel great! Mrs. Martin invites her

  • husband for ice cream as her treatment was so much cheaper. So what's happening

  • here? There are a couple of theories that try to explain the placebo effect. First

  • there is regression to the mean: Mr. Martin like most of us thinks about

  • treatment when his symptoms are particularly bad. He goes to see a doctor

  • and soon after feels better. If we look at the natural course of many illnesses

  • we understand that pain, over time, comes and goes in swings and usually regresses

  • to the mean. We don't know if the doctor or placebo had anything to do with the

  • improvement. Then there is classical conditioning:

  • most treatments, including vertebroplasty, are delivered in a context of rituals

  • that include social signals, physical cues, and verbal suggestions. Mr. Martin's

  • brain interprets such cues and elicits expectations memories and emotions, it

  • releases endorphins and other chemicals that make him feel good and lower his

  • perception of pain. So it becomes a self-fulfilling prophecy where a belief

  • that he feels better leads him to feel better. And there is confirmation bias: as

  • soon as Mrs. Martin takes the sugar pill she thinks she will feel better. Then she

  • focuses only on the things that confirm that she is better. She doesn't realize

  • that she still has trouble doing many other things. While all three ideas

  • probably work together there is another theory: so-called mirror neurons might

  • also play a role. A new and growing body of evidence points at brain cells that

  • mirror behavior. The cells fire when one acts and when one observes the same

  • action performed by another. As Mrs. Martin talks to the doctor parts of the

  • doctors brain will mirror parts of her brain and parts of her brain will mirror

  • his, as a result, the structure of her brain changes and she feels less pain.

  • The neurophysiologist Giacomo Rizzolatti who discovered mirror neurons suggests

  • that this process bypasses consciousness and provides a direct mapping of sensory

  • information onto motor structures.

  • Placebo, a Latin word that means "I will please", have been used for thousands of

  • years. Placebo effects have been discussed for centuries. An influential

  • study from 1955 by Henry Kay Beecher, Harvard, titled: the powerful placebo

  • established the idea that the effect is clinically important. Today the placebo

  • effect is well recognized and scientifically so significant that any

  • new pain medication that seeks Food and Drug Administration approval in the

  • United States needs to show that it works better than a placebo treatment. In

  • so-called randomized controlled trials, the gold standard of medical research,

  • one group of patients is given the new medication while a control group receives

  • a placebo. Neither the doctors who hand out the

  • medication nor the patients know who gets what. Once the trial is over results

  • are compared. If the new medication works significantly better than the placebo it's

  • allowed to be sold. The trial is surprisingly difficult from 10 new drugs

  • entering the test one gets approval. If a placebo study proves that an existing

  • standard medical procedure is ineffective, like in the case of

  • vertebroplasty, competent doctors stop prescribing it and we can speak of

  • medical reversal. To find out if an existing treatment works or if it's

  • healing power is just the result of the placebo effect we can administer

  • treatment without the knowledge of the patients. In one such experiment it was

  • shown that if a painkiller is administered by a hidden robot pump,

  • patients demanded twice the dose compared to when the drug is injected by

  • a nurse. This would suggest that if a patient is completely unaware that

  • treatment is being given, the treatment is just half as effective. The placebo

  • effect counts for the other half. Honest placebo studies go even further.

  • Because deception is ethically questionable researchers have now

  • started to do clinical trials in which people are told that all they get is a

  • sugar pill with placebo printed all over the packaging. And even then the placebo

  • effect does it's magic and helps you feel better.

  • One experiment at the Harvard Medical School showed that people suffering from

  • irritable bowel syndrome who were taking the honest placebo doubled their rate of

  • improvement compared to the control group. What do you think? How can we make

  • sure that the medicine we are prescribing is not only effective thanks

  • to the placebo effect? Will more placebo research reveal that many standard

  • medical treatments offered in some of the best hospitals around the world are

  • shams? And how can we research the power of placeboes ourselves, at home, without

  • putting anyone in danger?

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A placebo is a treatment with zero therapeutic value but magical healing

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