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Book Summary: The Expectation Effect – How Your Mindset Can Change Your World

The Expectation Effect (2022) explores the connection between our minds, our bodies, and our outcomes. It explores how our expectations can form our realities, and reveals the extent to which self-fulfilling prophecies shape our lives.

Book Summary: The Expectation Effect - How Your Mindset Can Change Your World

Content Summary

Who is it for?
Expect rituals to boost your performance
Expect mental simulation to enhance your abilities
Expect your willpower to be limitless
What’s in it for me? Discover the power expectations have on outcomes.
You have untapped reserves of mental stamina.
Placebos are powerful drugs, with many potential benefits.
In extreme cases, negative expectations can kill you.
Age is nothing but a number.
Final summary
About the author
Table of Contents
Read an Excerpt/PDF Preview
Video and Podcast

“Whether you think you can, or you think you can’t – you’re right.” – Henry Ford

In the following book summary, you’ll learn how “the expectation effect” can improve performance and increase willpower.


Behavioral Sciences, Cognitive Psychology, Personal Transformation Self-Help, Psychology, Philosophy, Wellbeing, Management, Health, Contemporary, Sociology

Who is it for?

  • Anyone struggling with a negative mindset
  • Psychology buffs looking for a fresh perspective
  • Health and wellness fans wanting new insights


“Our brain’s expectations are intricately woven into everything we experience.” – David Robson

  • In World War II, morphine was running low, so thousands of soldiers undergoing surgery were injected with a saline solution and told it was morphine. The placebo was 90% as effective as the actual drug!
  • In an antidepressant drug trial in Minnesota, a man took all 29 pills and was immediately rushed to the hospital. When he arrived, he was pale, drowsy, shaking, and had extremely low blood pressure. Doctors spent hours trying to improve his condition but couldn’t. When the doctor from the clinical trial arrived, he told the man that he had NOT taken the active drug and was overdosing on dummy pills. After hearing the news, the man made a full recovery.
  • In 2011, psychologist Dan Ariely handed out identical sunglasses to study participants and asked them to read words under the glare of bright light. Participants told they were wearing expensive Ray‐Ban sunglasses read twice as many words correctly as those who thought they were wearing mid‐market brand sunglasses.

These findings are examples of what scientists call the expectation effect. In the book, The Expectation Effect, author David Robson provides practical ways we can leverage the expectation effect in our lives and tap into our full potential.

Expect rituals to boost your performance

  • Serena Williams bounced the ball exactly five times before serving.
  • Rafael Nadal always took a cold shower before matches.

If you think these rituals seem like a waste of time, think again. Empirical research shows that rituals are powerful performance‐enhancing tools. A study in the Journal of Sports Sciences found that elite basketball players are 12.4% more likely to make a free throw if they execute their pre‐shot ritual than if they deviate from it. Rituals seem to work because executing a series of deliberate actions generates a sense of self‐control and concentration, which creates an expectation of continued self‐control and concentration.

After discovering the power of ritual, author David Robson started counting his coffee beans before making coffee for a writing session. He says, “It imbues my drink with a sense of significance and primes my mind for focus concentration.” Before any activity that requires total concentration, perform a ritual you believe will boost your performance.

  • Repeat your favorite quote or say a prayer.
  • Do a breathing exercise, like three deep diaphragmic breaths.
  • Listen to a specific song. If you pick a soundtrack song that makes you think of a character in a movie with heightened abilities, you might tap into the second performance‐enhancing expectation effect.

Expect mental simulation to enhance your abilities

When a group of cadets in officer training were given a standard eye test and then asked to go in a flight simulator and told to take the simulation seriously (like a pilot would), they read serial numbers on approaching planes in the simulation that were much smaller than text on the standard eye test they were unable to read.

Why could the cadets see better after imagining they were pilots?

The cadets expected pilots to have excellent vision, so their minds and bodies did what they could to improve their eyesight. You can use this finding by visualizing demanding situations to enhance your abilities ‐ whatever activity you’re about to do, imagine an extreme version of the activity that demands your best self.

  • If you’re about to play a chess game with a friend, close your eyes and imagine you’re sitting across from world champion Magnus Carlson – if you’re going to have any chance against him, you’ll need extreme levels of concentration and mental acuity.
  • Before a pickup basketball game with friends, imagine playing one‐on‐one with LeBron James and needing the quickness to defend against James’ drive. When you go to start the game with your friends, you might play the best basketball of your life.

Expect your willpower to be limitless

Think of a time you resisted a strong temptation, felt strengthened, and found it easier to withstand additional temptation.

Numerous studies show that those who adopt a “non‐limited” view of the mind’s resources recover faster from a tiring workday and achieve greater productivity the following day. In fact, people with a “non‐limited” view of willpower are more productive after demanding days.

Believing willpower is limitless should NOT give you the green light to work until you collapse ‐ the mind has a limit, but that limit is much further away than you think, and your ability to recover happens much faster than you believe.

“It is possible to push the limits of what we can achieve through a simple change of mindset.” – David Robson

Discover the power expectations have on outcomes.

It feels like the idea of “mind over matter” has a use in almost any scenario.

In sports, coaches preach the idea of using “mental toughness” to push past our body’s known physical limits.

In business, the saying, “if you can dream it, you can do it,” has practically become the go-to slogan for entrepreneurs and innovators worldwide.

And in medicine, even just receiving a diagnosis as being sick or healthy can make all the difference in how our bodies actually feel. Think about it – have you ever found yourself reading a list of symptoms for an illness, only to then begin feeling each of those very symptoms shortly afterward? Even if they weren’t there before?

But imagined or not, the concept of mind over matter has always left one lingering question: just how much can our mindset directly influence our reality? And to what extent do self-fulfilling prophecies actually end up shaping our lives?

David Robson, the author of The Expectation Effect, has an answer: quite a lot. And in this summary, you’ll discover the extent to which your mind is a powerful prediction machine, dedicated to making sure that your reality matches up with your inner expectations. From the aging process to the effects of medication on your body, you’ll uncover the power of the mind to change your productivity, your health, and your future.

In these summaries, you’ll learn

  • why age really is nothing but a number;
  • the effects placebo drugs have on your body; and
  • why pointing a kangaroo bone at someone could be fatal.

You have untapped reserves of mental stamina.

When Barack Obama was president of the United States, he wore almost exactly the same suit every single day. The only thing that varied was the color; the suits were either dark brown or navy blue. (Let’s forget about the tan suit fiasco.) Obama isn’t alone in his limited wardrobe choices, either. In fact, lots of highly successful people, like Steve Jobs, Ariana Huffington, and Mark Zuckerberg all prefer to wear the exact same outfit every day. Why? It all has to do with their expectations. But as you’ll discover in this summary, these expectations are totally wrong.

The reason why Obama and Zuckerberg dress the way they do is because they’re trying to get rid of unnecessary decision-making. For most of us, deciding what to wear each morning requires conscious thought. Do these pants match this shirt? Are these the best shoes to wear with this jacket? According to the theory known as ego depletion, we only have a limited amount of mental resources to use on decisions each day. After we’ve done a certain amount of hard work, or decision-making, or difficult thinking, those resources are exhausted. With this in mind, these leaders don’t want to waste their mental capacity on thinking about exactly what to wear.

On the surface, the ego-depletion theory seems to make sense. After all, how many times have you come home from a hard day’s work and felt too exhausted to do anything except lie on the couch? Some experts have even suggested that the reason why successful people cheat on their partners is because they’ve used up all their mental willpower on their career. They simply don’t have the capacity to work on their relationships.

But just how true is any of this? Because, in fact, other evidence suggests that the ego-depletion theory is instead just one big expectation effect. The mental exhaustion we feel after working hard is real, but it’s only real because we expect it to be. At least, that’s according to a study by Austrian psychologist Veronika Job. Job asked participants to complete two tasks in a row. Before they began the first task, Job asked each participant whether performing hard work usually a) depletes their mental resources or b) energizes them.

Interestingly, Job found that the people who had listed hard work as exhausting did much worse on the second task than they did on the first. In contrast, those who listed hard work as energizing performed evenly across both tasks.

Now, this might seem like the predictable outcome, but, in a follow-up study, Job then tested whether it was possible to change people’s beliefs and expectations about their own mental depletion. So, for this next study, before participants undertook the two tasks, they each read one of two statements.

One statement stated that hard work depletes our mental resources, and the other stated the opposite: that hard work has been proven to energize our minds so much that it actually enables us to thrive on other hard tasks once we’ve started. Job found that the people who had read the “energizing” statement performed twice as well on their second task as those who had read the “depleting” statement. All because their expectations had been shifted.

This just goes to show that our mental capacity is much greater than many of us believe. With the right expectations, we really can get more done. So, the next time you find your concentration waning in the middle of a hard task, try and remind yourself of a time when you found a challenging task energizing rather than draining. Then ask yourself whether that energizing task was objectively harder than the task you’re undertaking right now. Reframing how you view the challenging task at hand will help give your mental stamina enough of a boost to power through.

Placebos are powerful drugs, with many potential benefits.

Is it ever right for a doctor to lie to their patients? In the nineteenth century, US president Thomas Jefferson wasn’t so sure. On the one hand, he knew that it was morally ambiguous for a trusted doctor to deceive a patient. But on the other hand, Jefferson believed that placebos can do patients a world of good. Two hundred years later, science is beginning to understand that Jefferson might have been right.

A placebo is a dummy medication that contains no active ingredients. This means it has no physiological benefits or disadvantages for the person taking it.

Some of the first modern evidence of the benefits of placebos was collected by a military doctor during World War One. Henry Beecher was an anesthetist whose job was to treat Allied soldiers in France and Italy. These soldiers had come straight from the battlefield, and their wounds were often horrific and deeply painful. Worse still, the pain-killing drug morphine was in short supply, and Beecher was sometimes faced with the awful prospect of operating on these men without any anesthetic.

But during the course of his work, Beecher realized something remarkable. Oftentimes, a wounded soldier’s pain could be effectively treated with a simple saline solution. As long as the man believed that he was being injected with morphine, he would respond almost exactly as though he had been given the real drug. In fact, Beecher estimated that his placebo saline solution was about 90 percent as effective as morphine itself. It was so effective that it reduced the chance of the patient going into cardiac arrest while they were being operated on, which was a major risk during surgery without anesthesia.

Since Beecher’s pioneering discovery, placebos have been shown over and over again to have powerful effects. Consider recent evidence from people with Parkinson’s disease. Many of its symptoms, such as shaking limbs, are caused by a lack of dopamine in the brain. With this in mind, existing medications boost dopamine levels, which provides relief. Remarkably, though, when people with Parkinsons are given placebo drugs, their symptoms can improve by up to 30 percent.

How can we explain this? It may all come down to the patient’s expectations. Experts now believe that our brains act as the body’s internal pharmacy. When you expect to receive a benefit from a medication, your brain opens up its pharmacy, and releases biochemical substances that affect your body much in the way the real drug would. So in the case of the Parkinson’s placebo, the patient’s brain may have released more of its own dopamine or a dopamine-like substance.

Evidence for the pharmacy theory comes from a study that looked into placebo painkillers. The researchers believed that receiving a morphine placebo would stimulate patients’ brains into creating their own natural painkillers, known as opioids. To test this theory, the patients were also given another substance at the same time as the placebo. This substance was called naloxone; it effectively blocks opioid receptors in the brain. The researchers found that the naloxone stopped the placebo from working, just as they would have expected if they had administered it alongside actual morphine. This suggests that the placebo morphine really was stimulating the brain to produce its own opioids.

Interestingly, though, not all placebos have the same effect on us. Again, it comes down to our expectations. Studies have found that larger placebo pills produce a more beneficial effect than smaller ones. Similarly, placebos in the form of injections are then even more beneficial than pills. Finally, the biggest placebo effect is seen after surgery. So the greater expectations we have for the procedure, be it in the form of pills or surgery, the more placebo power we pump into ourselves.

With all this in mind, let’s return to that very first question that Thomas Jefferson grappled with. Is it ever right for doctors to deceive their patients? While we don’t have a clear answer, one thing is for sure. When we expect placebos to deliver powerful results, they tend to do just that.

Having learned this, how can you now apply this knowledge to your own health? First off, when you start taking medication, try to visualize the positive effects it could have on your body. Doing so could help these positive effects become a reality. Second, when you’re prescribed a drug, take the time to ask your physician exactly how it works to help your body. Just knowing this information may help in enhancing the effects of the drug. Finally, your expectations will receive a boost if you can talk to other patients who have used the same medication and found it effective. Simply knowing that it worked for other people may enhance the chances that it will bring benefits to you, too.

In extreme cases, negative expectations can kill you.

After discussing the positive effects expectations can have on our minds, it’s only fair to also lay out the risks of negative expectations. Let’s start with the opposite of a placebo. A nocebo. Placebo in Latin translates as “I shall please,” whereas nocebo means “I shall harm.” Just as our expectations can turn saline solution into morphine, they can also transform nocebos, harmless things, into deadly weapons.

It may surprise you to learn that one of the most ancient nocebos is a kangaroo bone. According to traditional Aborigine culture, a priest can use a kangaroo bone to put a deadly curse on someone. This ritual is fairly straightforward: the priest points the bone at someone and chants a deadly curse. And, within a few days, the cursed person’s body will begin to weaken, until, eventually, they fall down and die. According to nineteenth-century settlers who witnessed this phenomenon, it was as if the cursed person really did have a deadly hex on them.

Of course, with what we now know about the power of expectation on the body, it seems much less likely that these mysterious deaths were due to the supernatural. Instead, a more likely explanation could be that the kangaroo bone and the priest’s words acted as a powerful nocebo. Put another way, if you believe strongly enough that something is going to kill you, then you can actually bring about your own death.

Not convinced? Then consider the following infamous case of self-willed death. Let’s travel back to Nashville, Tennessee, in the 1970s. A man was diagnosed with terminal esophageal cancer. This came as a shock, especially since the cancer was so widespread that his doctor doubted that he would live to see next Christmas. Well, the man did live to see Christmas, but he died just a few weeks later, in January. Tragically, it seemed, the cancer had won. But when an autopsy was performed, the pathologist made a shocking discovery. There was no tumor on his esophagus. There was a tumor on his liver, but it was small, and certainly not terminal. But then, if that was the case, what caused the man’s actual death? With his dire diagnosis in mind, there was only one conclusion to be drawn: it was the doctor’s prognosis that had killed him. He had expected to die around Christmas of that year, and so he did.

Our negative expectations can harm our health in other ways, too. Often, the most potent nocebos come in the form of perceived side effects to real medications. This means that when we expect to suffer a side effect of a drug, we are more likely to experience it. Take, for example, a medication known as finasteride, which is used to treat enlarged prostates. An uncommon side effect of finasteride is erectile dysfunction. One study found that men taking finasteride were up to three times more likely to suffer from erectile dysfunction when they were explicitly warned that it was a potential side effect. In other words, many more men experienced a life-changing symptom simply because they were told about it.

Similar nocebo effects have been found in the use of aspirin to treat angina. Patients who were told that the aspirin might cause side effects of indigestion and stomach discomfort were six times more likely to stop the treatment than people who hadn’t been told about these side effects. And when asked their reason for stopping the treatment? Nausea and indigestion. This just goes to show that our expectations can, quite literally, make us sick.

If this news is starting to bring down your own health, there are luckily ways you can prevent harmful expectations from taking root. First, when a medication does come with the chance of an unpleasant side effect, try to reframe your thinking around your chances of experiencing it. For example, if you learn that one in ten patients suffers from a certain side effect, keep reminding yourself that that means that 90 percent of patients didn’t suffer from this side effect. So the odds of your suffering this are actually pretty low. Even just this simple reframing of expectations could prevent your body from needlessly developing these side effects on its own.

Age is nothing but a number.

Paddy Jones loves to dance salsa. Not just any salsa, but acrobatic salsa. This form of the dance involves swinging through the air on trapezes and requires perfect agility and poise. Jones is good at acrobatic salsa, too. So good, in fact, that she and her dance partner Nicko have been featured in television talent shows around the world, from the UK to Argentina. But Jones’s incredible salsa moves aren’t the only reason she’s become a dance sensation. It also has something to do with the fact that she’s 85 years old.

Ask Jones, and she’ll tell you that it doesn’t feel hard to dance acrobatic salsa at 85. Why? Because she doesn’t feel like she’s in her eighties at all. Inside, she feels like a much younger person, and so she expects to perform like a younger person, too.

And this makes sense. Evidence from Harvard University researchers suggests that how old we feel actually has a big influence on our abilities, our health, and even our appearance.

For example, in 1979, Harvard psychologist Ellen Langer conducted a study in which 70- to 80-year-old men and women were invited to spend a weeklong vacation at a secluded monastery. But this wasn’t just any monastery. Before the guests arrived, Langer’s team had turned the clock back 20 years. They decorated each room as if it were 1959, even going so far as to lay out magazines and newspapers from that exact year. They also asked their guests to spend the week discussing political and sporting events from 1959, as if they were taking place in the present, rather than in the past. Finally, they asked the guests to write a biography of their lives for the year 1959, including everything they had done during that year. Most importantly, this biography had to be written in the present tense. The goal was to make the guests feel as if they were really living in 1959, not 1979, and as if they were 20 years younger than their real age.

After the first set of guests returned home, Langer’s team brought in another group of 70 to 80 year olds. This group also spent a week in the monastery, but when they discussed events from 1959, they did so in the past tense. This was meant to make them feel as if 1959 was in fact 20 years ago, and that they were still their true ages.

After both groups’ stays were completed, Langer’s team compared a series of health and cognition tests taken before and after their monastery experience.

The results were astonishing. After spending a week imagining that they were 20 years younger, the first group performed significantly better on the cognitive tests than before their stay at the monastery. Not only that, but their vision also improved, they had better flexibility in their joints, and their levels of arthritic inflammation also improved. To top it all off, when independent observers, who were not part of the study, saw photographs of this group that were taken just after their monastery vacation, they rated them as looking significantly younger than the photos of the same group taken only a week earlier! Many of them said that this was due to their posture; after the study, they appeared to walk taller and more easily than before.

On the other hand, the second group of guests, who hadn’t been asked to imagine that they were living in the past, saw almost none of these improvements.

So, at the end of the day, maybe age really is nothing more than a number.

Final Summary

Your mind is a powerful tool in the fight against illness, inaction, and even aging. By visualizing positive outcomes for yourself, you make it all the more likely that those outcomes will become your reality. You might not be able to think yourself into becoming healthy, or young, but you can certainly create the right mental conditions to help you flourish.

To implement this into your daily life, here’s a quick piece of actionable advice to take with you: Find a way to channel high expectations

It’s hard to have a permanent positive mindset. So, instead, try and find something tangible to help steer your mindset. Like a lucky charm that an athlete might use – something that you can take with you on your daily routine. Even if it’s just for a special occasion like a big interview, if you can focus your expectation into this one lucky object, that might just provide that positive bit of expectation that you need to make a real difference. Because, as we learned from the kangaroo bone, a little superstition can go a long way if you believe it.

About the author

David Robson is a science writer, whose work has been published in the Times, the Guardian, the Atlantic, and the Washington Post. His first book, The Intelligence Trap, has been published in 15 languages.

David Robson is an award-winning science writer based in the United Kingdom. A graduate of Cambridge University, he previously worked as an editor at New Scientist and a senior journalist at the BBC. His writing has appeared in the Guardian, the Atlantic, Men’s Health, the Psychologist, the Washington Post, and many other publications. His first book, The Intelligence Trap, was published in 2019 and has been translated into fifteen languages.

David Robson | Website
David Robson | Twitter
David Robson | Linkedin

Table of Contents

List of Illustrations and Graphs
Chapter 1 The Prediction Machine: How your Beliefs shape your reality
Chapter 2 A Pious Fraud: How beliefs can transform recovery from illness
Chapter 3 Do No Harm: How expectations can hurt as well as heal-and how to break a curse
Chapter 4 The Origins of Mass Hysteria: How expectations spread within groups
Chapter 5 Faster, Stronger, Fitter: How to take the pain out of exercise
Chapter 6 The Food Paradox: Why indulgence is essential for healthy eating
Chapter 7 De-stressing Stress: How to turn negative feelings to your advantage
Chapter 8 Limitless Willpower: How to build endless reserves of self control and mental focus
Chapter 9 Untapped Genius : How to boost your own-and others’-intelligence, creativity, and memory
Chapter 10 The Super-Agers: Why you really are as young- or old-as you feel
Illustration Credits
About the Author


A journey through the cutting-edge science of how our mindset shapes every facet of our lives, revealing how your brain holds the keys to unlocking a better you

What you believe can make it so.

You’ve heard of the placebo effect and how sugar pills can accelerate healing. But did you know that sham heart surgeries often work just as well as placing real stents? Or that people who think they’re particularly prone to cardiovascular disease are four times as likely to die from cardiac arrest? Such is the power and deadly importance of the expectation effect―how what we think will happen changes what does happen.

Melding neuroscience with narrative, science journalist David Robson takes readers on a deep dive into the many life zones the expectation effect permeates. We see how people who believe stress is beneficial become more creative when placed under strain. We see how associating aging with wisdom can add seven plus years to your life. People say seeing is believing but, over and over, Robson proves that the converse is truer: believing is seeing.

The Expectation Effect is not woo-woo. You cannot think your way into a pile of money or out of a cancer diagnosis. But just because magical thinking is nonsense doesn’t mean rational magic doesn’t exist. Pointing to accepted psychology and objective physiology, Robson gives us the practical takeaways we need to improve our fitness, productivity, intelligence, and happiness. Any reader who wants to take their fate into their own hands need only pick up this book.

Read an Excerpt/PDF Preview


The mind is its own place and in it self

Can make a Heaven of Hell, a Hell of Heaven.

–John Milton, Paradise Lost

Our expectations are like the air we breathe—they accompany us everywhere, yet we are rarely conscious of their presence. You might assume that your body is resilient, or that it is prone to sickness. You might think you are naturally lean and sporty, or that you are predisposed to gaining weight. You might believe that the stresses in your life are harming your health, and that a night of poor sleep will render you a walking zombie the next day.

These assumptions may appear to be inescapable, objective truths. But in this book I will show you how those beliefs, in themselves, shape your health and well-being in profound ways, and that learning to reset our expectations about these issues can have truly remarkable effects on our health, happiness, and productivity.

Don’t believe me? Then consider one attention-grabbing study from Harvard University. The participants were hotel cleaners, whose work is often physically intense yet feels very different from the exercise you might perform at the gym. To change the cleaners’ perceptions of their own fitness, the researchers explained the amount of energy that was exerted by vacuuming the floor, changing beds, or moving furniture—which, over the course of a week, easily amounts to the level of exercise recommended for good health. One month later, the researchers found that the cleaners’ fitness had noticeably improved, with significant changes in their weight and blood pressure.1 Quite amazingly, the shift in their beliefs about their bodies, and their new expectations of their work, had brought about real physiological benefits—without any change in lifestyle.

We will discover how “expectation effects” like this can also influence our susceptibility to illness, our ability to maintain a stable body weight, and the short- and long-term consequences of stress and insomnia. As the following story shows, the power of expectation is so strong that it can even determine how long you live.

* * *

Starting in the late 1970s, the US Centers for Disease Control began to receive reports that a worrying number of recent Laotian immigrants were dying in their sleep. They were almost all male, aged between their midtwenties and midforties, and most were from the persecuted Hmong ethnic group who had fled Laos after the rise to power of the Pathet Lao. For their loved ones, the only warning was the sound of them struggling for breath and, occasionally, a gasp, a moan, or a cry. By the time help arrived, however, they were already dead.

Try as they might, epidemiologists could find no good medical explanation for these “Sudden Unexpected Nocturnal Death Syndrome” cases. Autopsies showed no evidence of poisoning; nor was there anything particularly unusual about their diet or their mental health. At its peak, however, the mortality rate was so high among young Hmong men that SUNDS accounted for more lives lost than all the other top five causes of death combined. Why were so many seemingly healthy adults passing away in their sleep?

Investigations by the medical anthropologist Shelley Adler would eventually solve the mystery. According to Hmong traditional folklore, an evil demon called the “dab tsog” roamed the world at night. When it had found its victim, it would lie on the body, paralyzing the victim and smothering their mouth until they could no longer breathe.

Back in the mountains of Laos, the Hmong could ask a shaman to build a protective necklace, or they could sacrifice animals to appease their ancestors, who would fend off the dab tsog. But now these men were in the United States—there were no shamans, and they were no longer able to perform their ritual sacrifices to appease their ancestors, meaning they had no more protection from the dab tsog. Many had converted to Christianity so that they could better integrate into American culture, neglecting their old rituals altogether.

Guilt at having abandoned their traditions was itself a source of chronic stress that could have harmed their overall health. But it was at night that the fears of the dab tsog became a reality, with disturbing nightmares that resulted in the experience of sleep paralysis, in which the mind becomes conscious, as if you were fully awake, but the body is unable to move. Sleep paralysis is not in itself dangerous—it affects around 8 percent of people.2 For the Hmong immigrants, however, it seemed like the dab tsog had come to wreak revenge. The result, Adler concluded, was a panic so strong it could exacerbate a heart arrhythmia, leading to cardiac arrest.3 And as the deaths mounted, the Hmong men only became more scared, creating a kind of hysteria among the population that may have caused even more deaths. The explanation is now accepted by many scientists.4

Newspaper reports at the time described the “cultural primitivity” of these people, who were “frozen in time” and “ruled by superstition and myth.” But scientists now argue that we are all susceptible to beliefs that are just as potent as the dab tsog. You may not believe in demons, but thoughts about fitness and expectations about long-term health may have real consequences for your longevity, including the risk of heart disease. This is the enormous power of the expectation effect. It is only once we recognize its influence that we can begin to use it to our advantage to ensure a longer, healthier, happier life.

These provocative claims may sound dangerously close to the content of many New Age self-help books, such as Rhonda Byrne’s 35-million-copy best seller The Secret. Byrne promoted the “law of attraction”—the idea that, for example, visualizing yourself rich will bring more money into your life. Such ideas are pure pseudoscience, whereas the findings in this book are based on robust experiments published in peer-reviewed journals, and they can be explained by well-accepted psychological and physiological mechanisms, such as the actions of the nervous and immunological systems. We will learn how our beliefs can influence many important life outcomes without any appeal to the paranormal.

You may also wonder how the content of our thoughts could have any meaningful influence in the chaos of the world today. I wrote much of this book in the midst of the Covid-19 pandemic, when many of us were grieving for loved ones and fearing for our livelihoods. We have also faced huge political uncertainty and unrest, and many continue to wrestle with enormous structural inequalities. Our own expectations and beliefs may seem to hold little power in the face of all these barriers.

It would be foolish to argue that “positive thinking” could eliminate all this unhappiness and anxiety—and I would be the last person to make that claim. (Scientific research continues to show that simply denying the difficulties of a situation will only lead to worse outcomes.) As we shall soon see, however, there are many ways that our beliefs about our own capacities can influence how we cope with challenges, and can determine the toll they take on our physical and mental health. While many of today’s crises are beyond our control, our responses to difficult situations are often the product of our expectations—and understanding this allows us to increase our resilience and to react in the most constructive way to the problems we face.

Crucially—and this is something that I will emphasize throughout the book—the expectation effects described in these chapters concern specific beliefs rather than a general optimism or pessimism. Armed with scientific knowledge about the ways your expectations are shaping your life, you can learn to reframe and reappraise your thinking without any self-deception, and you don’t need to turn into a cheery Pollyanna to benefit.

* * *

My own understanding of the enormous power of expectations came seven years ago during a period of turmoil in my own life.

Video and Podcast


“As David Robson makes plain in this compelling book, the way we think about the world can profoundly shape how we navigate it. Based in science and packed with smart advice, The Expectation Effect will expand your mind―and maybe even extend your life.” – Daniel Pink, New York Times bestselling author of When, Drive, and To Sell Is Human

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“A fascinating exploration of the ways in which our brains can sabotage or save us in our most challenging moments.” – Salon

“If you’re looking to make major or minor changes in your life, this book will help you leave the starting gate with positive expectations of success.” – New York Journal of Books

“[The Expectation Effect] made me realize that I’m leveraging far fewer of my brain’s features than I could be…. What scientists are learning about the connections between the human brain and performance is incredible. And David Robson manages to take this research and organize it into a compelling playbook for a better life.” – Gayle Allen, Curious Minds at Work podcast

“Mind-changing science…One of Robson’s many strengths as a chronicler of science is to take what might seem familiar and show…just how much deeper the rabbit hole goes…. The book abounds in compelling anecdotes…Robson’s central point is that the expectation effect isn’t an amusing psychological quirk, but a fundamental aspect of our interactions with reality…. The result of marinating for a while in this outlook is surprisingly transformative.” – Oliver Burkeman, New York Times bestselling author of Four Thousand Weeks: Time Management for Mortals, reviewing for The Guardian (UK)

“We’re six days into 2022 and The Expectation Effect by David Robson is already threatening to be book of the year―visionary, original, and exciting, like all the best science writing.” – Will Storr, author of The Science of Storytelling

“As David Robson makes plain in this compelling book, the way we think about the world can profoundly shape how we navigate it. Based in science and packed with smart advice, The Expectation Effect will expand your mind―and maybe even extend your life.” – Daniel Pink, New York Times bestselling author of When, Drive, and To Sell Is Human

“This is an utterly riveting and transformative book. You can’t afford not to read it!” – Nigella Lawson

“Citing examples across the spectrum of human behavior, Robson shares compelling studies and anecdotal evidence to suggest that what people think will happen often turns into a self-fulfilling prophecy…. In The Expectation Effect, he more than meets his goals of equipping readers with a critical understanding of how expectations shape lives and providing practical tools for reframing and adjusting mindsets toward positivity and well-being.” – Shelf Awareness

“The human brain, according to this absorbing book, has a mind of its own…. Cutting-edge research and effective storytelling create an insightful book on an ever changing field.” – Kirkus Reviews

“A fascinating, optimistic, and empowering book. David Robson uses science and stories to show the extent to which we are shaped by our beliefs, and how the predictive power of our brains influences pain, diet, sleep, exercise, and intelligence.” – Dr. Monty Lyman, author of The Remarkable Life of the Skin and The Painful Truth

“Authoritative, measured, practical, and encouraging, it will change your attitude to life’s challenges.” – Dr. Christian Jarrett, author of Be Who You Want

“An intriguing account of the role of expectation (and perception in general) in a wide panorama of experience. Beautifully written, science-based, and a gripping read. I loved it!” – Dr. Mithu Storoni, author of Stress-Proof

“As a counter to the many ‘pseudoscientific’ self-help books about the power of expectations (most notably, The Secret), Robson investigates the ‘expectation effect’ through peer-reviewed experiments and studies…there are plenty of valuable takeaways…a fine place to start for readers interested in the power of the mind.” – Publishers Weekly

“The consistently brilliant David Robson is back, packed with science, stories, and practical tips for anyone who wants to make better use of the remarkable body–mind connection.” – Kerry Daynes, bestselling author of The Dark Side of the Mind and What Lies Buried

“This book is entertaining, eye-opening, extremely useful, and best of all, evidence-based.” – Claudia Hammond, author of The Art of Rest

“The Expectation Effect is a must-read book that shows how we can all use our brainpower to improve our lives. Whether it’s medicine, anxiety, exercise, or diet, David Robson seamlessly and engagingly explores how what we expect to happen has a much larger role than we might have previously believed―and we can tap into that power to improve our own well-being…. If you want to learn how to reframe your mindset, to feel healthier and happier in the process, this book is for you.” – Melissa Hogenboom, author of The Motherhood Complex

“How on Earth does a person pack in so much research and yet still make it fascinating and fun to read? Through the perfect mix of stories, stats, and science, David Robson makes a very persuasive case that what we expect has a significant material impact on our lives―and how we can harness this to live longer, happier, healthier, more successful lives.” – James Wallman, author of Stuffocation and Time and How to Spent It