The placebo effect
Is it possible to cure all diseases with the power of thought
Alexander Thostov, Post-science
Does Chinese medicine work? Can homeopathy cure a person? Supporters of alternative medicine can be shown masses of scientific articles about the ineffectiveness of such methods, but arguments sometimes clash with a person's personal experience: for example, he knows for sure that he took homeopathic medicines — and he got better. But how is this possible if homeopathy doesn't work? Psychologist Alexander Thostov talks about whether faith in the drug can cure a person, how the situation in the doctor's office affects the patient and why it is not worth scaring him with side effects from drugs.
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Mr. Wright was dying of lymphosarcoma. According to his attending physician, the tumors in his body reached the size of an orange, the liver and spleen were excessively enlarged, fluid accumulated in his lungs, which had to be pumped out every two days, and very often he needed additional oxygen. The doctors were sure that they could not do anything more for their patient: the disease had already passed into the terminal stage.
However, Mr. Wright himself did not think so. The fact is that a new cancer drug called krebiozen was about to be released, and Mr. Wright was absolutely sure that this drug would instantly put him on his feet. Krebiozen had not yet been tested at that time, and only a small batch was received at the clinic to test its effectiveness, but Mr. Wright persuaded doctors to try the drug on him as well. He received his first injection on Friday, and on Monday he was no longer recognizable: the former bedridden patient was now walking around the ward and chatting with the nurses, and his tumors had halved — although no positive dynamics was observed in all other patients who received krebiozen. In just ten days, almost all of Mr. Wright's symptoms disappeared.
Two months later, the results of krebiozen's clinical trials were published in the press: all the clinics where he was admitted for testing reported on his complete inefficiency. From this news, Mr. Wright lost faith in the drug, fell into despondency and gradually returned to his former state — and then his attending physician deliberately deceived him: he told his patient that he did not need to believe the newspapers and that an improved formula of the drug, which was devoid of the shortcomings of the previous version, would soon arrive at the clinic. Mr. Wright cheered up, the doctors injected him with the same "improved formula" of the drug — and everything happened again: in a matter of days, the tumors decreased, and all the symptoms of the disease almost completely disappeared.
There is only one small detail: that "improved formula" was... plain water.
This story, which was described in 1957 by psychologist Bruno Klopfer, is a classic example of the placebo effect (from lat. placebo — "you'll like me") — that is, the improvement of the patient's condition against the background of taking a substance that has no medicinal properties. Such a substance — it is called a placebo itself — can be, for example, sugar or starch in tablets or saline solution in the case of injections: if the patient believes that he is actually receiving medicine and expects improvements, he may well feel them. In some cases, researchers offer a broader definition: the placebo effect can be understood as any improvements related not to the therapeutic effect of the drug, but to the circumstances in which this drug was obtained — for example, from a doctor in a white coat in a polyclinic — and the patient's faith in its efficacy.
Studies show that the placebo effect is observed in about one in three people: such people will feel an improvement even if the drug is ineffective — as was the case with Mr. Wright. Unfortunately, his story has a sad end: after the second course of placebo injections, the symptoms of his illness almost completely disappeared for two months — but after that, a report by the American Medical Association appeared in the press, which came to the final conclusion that krebiozen is ineffective in the treatment of oncological diseases. After this news, in just a couple of days, Mr. Wright's condition worsened so much that he went back to the hospital, and a few days later he died [1].
How real are the placebo effects?
How can one explain such a striking dynamic of Mr. Wright's condition? How much can a person's condition improve under the influence of the placebo effect? It all depends on what diseases and symptoms we are talking about. Of course, the improvement of well—being can be purely subjective - when the patient feels that he has become better, but at the physiological level there have been no significant changes in his body. Where do the improvements come from? The fact is that without additional analyses and studies, a person can rely only on his own feelings in assessing his well—being: we do not have our own microscope and X-ray machine built into us, and if we are sick, we can only find out by our feelings, first of all - bodily, for example, pain, general malaise, weakness or broken. Such feelings are very vague, and it is impossible to check or control them; if a person is in a state of anxiety, he will find more of them than when he is calm. It is because of this that some people have a "medical student syndrome", in which a person can find symptoms of those diseases that he reads about - like the narrator in the story of Jerome K. Jerome "Three in a boat, not counting the dog." Accordingly, if a person expects improvement and calms down, it is quite possible that his subjective assessment of his condition will improve in accordance with expectations — and this is an important component of the placebo effect.
The placebo effect has the opposite effect — nocebo (from Latin. nocebo, "I will hurt"): it is characterized by a decrease in the patient's well—being against the background of taking the drug - both a "dummy" and an active drug. The nocebo effect has been studied worse than the placebo effect, but studies show that if a patient is afraid of side effects from the drug or does not believe in its effect, it may seem to him that his health has not changed or worsened at all during treatment, and the disease has not disappeared. This should be remembered by both patients and doctors when they explain to patients the principles of action of drugs and possible side effects.
But in some cases, improvements may be more objective: for example, the placebo effect may affect the work of the immune or neuroendocrine systems of the body. So, researchers at the University of Utah studied how much the placebo effect depends on the subjects' ideas about the strength of the drug. An experimenter in a white coat with a large badge on which was written the name of the research center — "Center for the Study of Pain" — told the subjects that they were testing a new painkiller cream. He explained that as part of the experiment, participants will be applied cream A (the strongest analgesic), cream B (the weaker analgesic) to different areas of the hand and cream C (control, which has no analgesic effect) to check their effectiveness. In fact, all three creams were the same placebo, but poured into labeled packages associated with medical drugs, and having a pronounced "medicinal" smell.
In the first phase of the experiment, all three types of cream were applied to the skin of the subjects and the pain stimulus was reported — the minimum on the skin area with cream A ("strong analgesic"), the average on the skin area with cream B ("moderate analgesic") and the maximum on the skin area with cream C ("control sample"). The subjects were informed that the pain stimulus was the same in all three cases. This allowed the authors of the experiment to form in the subjects the expectations necessary for the experiment — that analgesic A is indeed the strongest, and control cream C does not have an analgesic effect.
Having fixed the corresponding expectations, the authors moved on to the main phase of the experiment. This time, the pain stimuli in all three cases were the same, but at the same time, the physiological parameters of the response to the stimulus were measured in the subjects: pupil dilation, skin conductivity level and electroencephalography data. As a result, the study showed that even when the pain stimuli remain the same, the physiological response in the case of "different" creams differs: it is the least intense when stimulating a skin area with the "strongest analgesic" and the most intense when stimulating a skin area with a "control" cream [2]. Thus, the researchers were able to form a placebo effect in the subjects using both the external context — the laboratory environment, the experimenter's white coat, the specific smell of the cream and the packaging design — and internal expectations and memories. The placebo effect itself affected not only the subjective perception of pain, but also the physiological response to the stimulus.
In the same way, a person's expectations can affect the work of his immune system. The relevant studies are built in much the same way as described above: first, learning occurs when a connection between a stimulus and a reaction is formed in the subject, and then the stability of this connection is checked. For example, if you associate a drink of a certain taste with taking immunosuppressants, then later such a drink itself can cause suppression of immune system reactions [3], although it is difficult to say exactly how the brain causes such effects. In addition, the placebo effect can also manifest itself with the development of inflammatory reactions: for example, taking an "antihistamine" drug, which is actually a placebo, can weaken allergic urticaria [3] if the patient has read the advertising of this drug.
With oncological diseases, everything is more complicated. On the one hand, the medical literature describes cases like Mr. Wright's story, when the placebo effect allowed a sharp and completely unexpected change in the course of the disease — but on the other hand, most studies agree that the placebo effect can reduce pain or improve the patient's appetite, but almost does not affect the size and density of the tumor. So, in the late 1980s, a special commission investigated the effectiveness of the drug "katrex", declared as an extremely effective drug for the treatment of cancer. Clinical trials have shown that katrex does not work, but many patients nevertheless believed in it and turned to it in the hope of healing, and 62% of such patients after taking it noted subjective improvements — for example, a decrease in pain or a surge of strength. Some claimed that they also felt objective improvements — for example, a decrease in the size of the tumor or swelling — but the measurements did not confirm this.
It is curious that some patients could associate any changes in well—being with the "positive effect" of the drug: if the body temperature returned to normal, this was regarded as a sign of the drug's work, but if the body temperature increased, this was also attributed to the fact that the drug acts and thus fights the tumor. In general, subjective improvements depended on how much the patient knows about the drug and believes in its success: the more detailed the patient's ideas about the principles of the drug and the more he wanted to access it, the more improvements he felt.
Psychology of placebo
The occurrence of the placebo effect can be explained in terms of different approaches and theories. One of these approaches is the conditioned reflex theory: if you associate an unconditional stimulus (an active drug) with a neutral stimulus (a placebo), and then reduce the dose of the drug or abandon it altogether, one placebo may be enough for the body to have a reaction. Thus, it was shown in rats: if they are regularly injected with scopolamine, and then continue to be injected according to the same schedule, but instead of the drug to inject regular saline, rats exhibit the same behavior as after injection of scopolamine [4]. Different research groups successfully formed a conditioned reflex in the subjects and provoked them, for example, a certain immune response, the production of certain hormones or a decrease in pain.
But despite the fact that unconscious processes obviously play an important role in the formation of the placebo effect, we must not forget about the patient's expectations — both conscious beliefs that he can utter and explain, and unconscious ones that nevertheless affect his psychophysiology. In other words, the placebo effect also depends on the context in which the treatment takes place — both external and internal. So, the patient is affected not only by the fact that he takes the medicine: the circumstances in which he received this medicine are also important for him. For example, a treatment room in a polyclinic can be perceived as a place where a person receives treatment, a doctor's white coat as a sign of his professionalism and responsibility and a guarantee that the patient's health is in safe hands. Verbal signals also play an important role — for example, if a doctor says: "You will feel better soon" when prescribing a drug to a patient — and his tone is no less important here than the words themselves. The internal context can be knowledge about the drug, the emotional state of the patient — for example, that against the background of taking the drug, he experiences less anxiety and feels that he is being taken care of — as well as memories: if the patient has already taken this drug once, and it worked well, the patient can expect improvements this time.
Why does the placebo effect not occur in all people? Studies have shown that the formation of the placebo effect is influenced by the peculiarities of the patient's cognitive style — in particular, self—dependence - as well as his level of bodily perception. The concept of field dependence describes a cognitive style in which a person is characterized by reliance on context, whereas field-dependent people can overcome the influence of context and rely on their own feelings. Thus, a health-dependent person, when taking a drug, is more likely to pay attention to the surrounding environment, and, as a result, will be more susceptible to the placebo effect.
On the other hand, in order for the placebo effect to occur, a person must be aware of his feelings — feel changes in well-being and be able to describe them. This skill is called bodily perception: the higher its level, the better such sensations are represented in a person's mind, which means the higher the probability that he will pay attention to their smallest changes — or it will seem to him that they occur if he expects to feel them.
Why do we need a placebo effect?
Now placebo is widely used in clinical trials: to determine the effectiveness of the drug, researchers need to separate the effects of taking the drug from the placebo effect. To do this, two groups are formed — one receives a real drug, and the other a placebo, and none of the study participants knows which group he is in: this way you can compare the effectiveness of the drug in both groups and understand how effective it is. In some cases, doctors prescribe ineffective drugs to patients — either out of ignorance, or because there are no proven drugs for this disease yet, or they exist, but they do not work for a particular patient, and it remains only to hope for a placebo.
But if we understand the placebo phenomenon more broadly — as any improvement associated not with the pharmacological effect of the drug, but with the psychological mood of the patient — then studies of the mechanisms of placebo will enhance the effectiveness of proven drugs whose work has already been proven as a result of clinical trials. If we know that the patient's belief in the effectiveness of an analgesic reduces his pain, then we can prescribe him a good analgesic and try to form positive expectations in him — for example, explain to him the principle of the drug or provide emotional support — and thereby enhance the real medicinal effects. Further studies of the psychological mechanisms underlying the placebo effect will help scientists and physicians to better understand how the brain and consciousness affect the endocrine, immune, cardiovascular and other human systems, and based on this knowledge to develop new, even more effective methods of treatment.
Literature
- Bruno Klopfer. Psychological Variables In Human Cancer. Pages 331-340. 2010
- Nakamura Y, Donaldson GW, Kuhn R, Bradshaw DH, Jacobson RC, Chapman RC. Investigating dose-dependent effects of placebo analgesia: a psychophysiological approach. 2012
- Wager TD, Atlas LY. The neuroscience of placebo effects: connecting context, learning and health. 2015
- Peiris N, Blasini M, Wright T, Colloca L. The Placebo Phenomenon: A Narrow Focus on Psychological Models. 2018
About the author:
Alexander Thostov – Doctor of Psychological Sciences, Professor, Head of the Department of Neuro- and Pathopsychology of Lomonosov Moscow State University; President of the Moscow Psychoanalytic Society.
Portal "Eternal youth" http://vechnayamolodost.ru