Tensions of The Placebo Effect

Are you more intelligent than your peers? Men are more likely to overestimate their intelligence by 5 points, while women are more likely to underestimate their IQ by a similar margin according to a study evaluating gender role differences.

The Dunning–Kruger effect suggests that people with low ability at a task tend to overestimate their own ability, while people with a high ability tend to underestimate their own ability. This finding was awarded the Ig Nobel prize which is a satire prize to — "honour achievements that first make people laugh, and then make them think."

Believing Your Own Hype: The Dunning-Kruger Effect - Flofinder
Image Credit. Believing Your Own Hype: The Dunning-Kruger Effect

After a hearty laugh reflecting on our own misperceptions, the deeper psychological question to examine is — “What is the function of our delusions?”. One of the marvels of the human mind is the mechanism and intricacies of the placebo effect. Understanding the purpose behind them can give us the tools to dismantle harmful delusions and embrace the useful ones.

Why do we have helpful delusions?

In any given moment, our eyes take in about a billion bits of information as explained by NPR's social science correspondent Shankar Vedantam (author of Useful Delusions). If all this information was transmitted to the brain, we would get overwhelmed with the enormous sensory overload. By filtering in 1 out of 1000 bits, we pass on a million bits to the brain and then process around 40 bits of this information. Starting with a billion bits, our brain processes just 40 bits of information which is how we have learned to make sense in a world of plentiful stimuli.

The book highlights that for decades, people believed that if you have depression or anxiety, you are seeing the world with a delusional pessimism. Many recent studies have now terminated this notion and find almost the opposite to be true. People with mental health challenges are often in fact seeing the world more accurately. This suggests that seeing the world through rose-tinted glasses can help us maintain our own mental wellbeing, as well as facilitate our ability to help others with more compassion.

How does the “placebo effect” change the mind?

The brain is a simulation device. It takes the past, applies it to the present moment and makes predictions for the future. These experiences from the past are used to generate simulations to map the world. When you give someone a sugar pill and their pain goes away, it’s because the brain has an expectation that the pain will go away. It can be very difficult to break hardwired expectations and placebos take advantage of the fact that the brain doesn’t want to divert from expectations. Sometimes it is easier to change reality than it is to change an expectation.

The mind simulates the experience of feeling better, which becomes a reality, both physically and psychologically. These social nuances and stories we tell ourselves is a major part of what it is to be human. As Krista Tippett (podcast host of Onbeing) summarises this — “it’s about us”.

What does the placebo effect look like in practice?

According to Erik Vance (science journalist), these are more than just sugar pills for the healthcare industry. All the theatre surrounding medicine contributes to our belief that we will get better. For example, people respond better to medication when they see the physician administering pain medication. This medication works better compared to instances where patients do not see the medicine being loaded to the intravenous (IV) for treatment. The theatre around medicine involves white lab coats and this is something that we identify with getting better.

The weird power of the placebo effect, explained. Brian Resnick Vox, 2017.

The placebo effect is not unlimited in practice, we just haven’t figured out the boundary conditions. Something to keep in mind is that the placebo does not affect everything equally. Things like pain, irritable bowel syndrome, parkinson’s disease, anxiety and depression have high placebo response rates. But other medical conditions like alzimers, cancer, autism and obsessive compulsive disorder have a low response rate to placebos.

Reflections on the placebo dilemma.

#1 Power vs trust - Should a doctor take advantage of their “power” over the patient so that they start to feel better? It’s a complex question, because if doctors start lying to patients to elicit the placebo effect, this can break the doctor-patient trust and potentially reduce the power of the placebo effect going into the future. 

#2. Nocebo effect vs Placebo effect - The nocebo effect harnesses the desire that our brains have to simulate the future that we may experience, and channels our predictions towards fear. Most of the evidence suggests that nocebos are easier to create and they last longer. If a placebo is something that will make your pain go away, you can think of a nocebo as something that will really hurt. 

#3. Pain vs gain - A higher price can create the impression of higher value, just as a placebo pill can reduce pain. Researchers have combined the two effects and find that a $2.50 painkiller works better to reduce pain than one that costs 10 cents for the exact same product. This higher price can fail to help lower income people from feeling the same pain relief as they may be more price sensitive.


Szymanowicz, A., & Furnham, A. (2013). Gender and gender role differences in self-and other-estimates of multiple intelligences. The Journal of social psychology, 153(4), 399-423.

Resnick, B. (2017). The weird power of the placebo effect, explained. Vox.

Useful Delusions: The Power and Paradox of the Self-Deceiving Brain (Book by Shankar Vedantam and Bill Mesler)

Krys Boyd interview with Shankar Vedantam (Hidden Brain podcast episode)

CaRey, B. (2008). More expensive placebos bring more relief. The Nova York Times.

The Drugs Inside Your Head (On Being podcast episode)

Suggestible You: The Curious Science of Your Brain's Ability to Deceive, Transform, and Heal (Book by Erik Vance)

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