The Expectation Effect

# The Expectation Effect Expectations are more than loose thoughts about the future. They often function like a kind of mental operating system: background software that continuously interprets what’s happening, predicts what will happen next, and adjusts our bodies and behavior accordingly. Sometimes this operating system is helpful and realistic. Other times it is misaligned, colored by fear, pessimism, or fixed assumptions — and then it can contribute to producing more of what we are actually trying to avoid. There is a sentence that captures this elegantly: "We don’t see things as they are, we see them as we are," wrote Anaïs Nin. The point is not that reality is optional, or that we can think away everything that is difficult. The point is that we always meet reality through an interpretive filter. And this filter — attitudes, expectations, core assumptions — influences emotions, choices, persistence, relationships and in some cases even physiology. This text is about the expectation effect: how what we expect can become self-fulfilling prophecies, how the placebo effect shows that the brain can act like a "pharmacy," and why it’s wise to balance optimism with realism. Along the way I draw on research from Yale and on David Robson’s book *The Expectation Effect*, which collects and discusses a wide range of findings in this field. ## Self-fulfilling prophecies — expectations that carve tracks A self-fulfilling prophecy describes a process where an expectation (conscious or unconscious) influences behavior and interpretation so that the expectation actually becomes more true. It is a psychological phenomenon with many faces. A simple example: If I enter a meeting expecting criticism, I will often be tenser, more self-critical, and more guarded. I might speak less, smile less, and interpret neutral comments as negative. The other person notices my unease and may become more cautious or more direct. In the end the conversation can actually feel critical and unsafe — and I "was right." Reality is not created by magic but through small, systematic adjustments in how we act, what we pay attention to, and how we interpret signals from others. This applies in relationships, at work, in health, and in how we approach aging. What’s striking is that we often underestimate how strongly these micro-mechanisms can operate over time. Many of us think attitudes are just "thoughts," and that thoughts float around without much effect. But expectations are not just words in the head. They are predictions the brain uses to regulate attention, stress response, motivation, and interpretation. That is why they easily become a guiding force in life. ## Aging as an example: seven years difference in lifespan One of the most striking findings about the importance of expectations comes from the research of Becca Levy at Yale School of Public Health. Levy analyzed data from a long-term study on aging and retirement age with over a thousand participants. The study began in 1975. Participants were on average 63 years old at the time and were asked about their attitudes toward aging. They responded to statements such as: - "You are less useful as you get older." - "Age brings valuable life wisdom." The participants were then followed for decades. The results are remarkable: the most age-positive lived on average seven years longer than the others. - The most positive about aging lived on average another 22 years from 1975, reaching about 85 years old. - Participants with more negative attitudes lived on average another 15 years, reaching about 78 years old. What is methodologically interesting is that the difference persisted even after the researcher controlled for important factors such as health at study start, socioeconomic status, and feelings of loneliness. In other words: this cannot be reduced to "those who were healthier were more positive." The attitudes themselves appear to be part of the explanation. How can this be possible? A sober interpretation is that attitudes about aging influence health through several channels simultaneously: 1. **Behavior and health choices:** If I expect aging to mean decline, I may be more likely to give up: exercise less, be less social, and interpret bodily changes as "proof" that I’m getting worse. If I expect aging can also bring maturity and meaning, I’m more likely to take care of my health and relationships. 2. **Stress and physiology:** Negative expectations can increase baseline tension, worry and stress. Over time this affects immune function, sleep, inflammation and cardiovascular strain. 3. **Interpretation and coping:** Optimism can boost problem solving and persistence: "I can handle this," rather than "This is the end." That leads to more active coping. This does not mean optimism "guarantees" a long life, or that disease is caused by incorrect thinking. It means expectations are one factor that can tip the balance of overall health in a more or less beneficial direction. ## The mental operating system: everything we think and feel can be wrong A somewhat challenging but liberating thought is that everything we think and feel can be wrong — meaning: feelings and thoughts are not direct bearers of truth. They are signals and interpretations. Feelings feel true because they are strong and bodily. But a feeling is primarily an assessment: the brain makes a lightning-fast interpretation of the situation and the body mobilizes. If the interpretation is skewed (for example because it is colored by past experiences or expectations), the feeling can be misleading. This is central in modern psychology: we try to distinguish between experience and reality without undervaluing the experience. The experience is always real in the sense that it is felt. But it can still be a poor guide. Expectations act as a kind of "pre-interpretation." They determine what we look for, what we notice, and what we ignore. Over time this can become a fixed style: we see the world in a way that confirms our starting point. ## "Mind over matter" — an idea that needs nuance The idea that the mind can influence the body, often phrased as "mind over matter," can be both inspiring and misunderstood. On one hand, there is solid evidence that psychological processes affect physiology. Stress affects the immune system, sleep affects mood, expectations affect pain experience. Mind and body are not two separate worlds. On the other hand, there is a myth that "the power of thought can overcome all physical limits." That myth quickly becomes a burden: if you don’t recover, "you didn’t think right." If you’re exhausted, "you lack willpower." Such thinking overlooks biology, chance, genetics, life circumstances and pure luck/misfortune. A more mature position is: **Expectations can influence a lot, but not everything.** They can change probabilities, not suspend physics. They can increase coping and reduce strain, but they cannot always change baseline conditions. It is in this balance — between optimism and realism — that the expectation effect becomes useful. ## David Robson and the psychology of expectation David Robson’s book *The Expectation Effect* examines how expectations shape everything from pain to performance, from stress response to aging. The valuable part of this approach is that it tries to understand expectation as a psychological mechanism, not as "positive thinking" in an advertising sense. Expectations can arise from: - past experiences - culture and societal narratives - family attitudes - bodily signals (which we interpret in light of assumptions) - authorities (doctors, teachers, leaders) They are, in other words, learned — and therefore often possible to adjust. ## Hard work: energizing or draining? A particularly interesting area is how expectations affect performance in demanding tasks. Some people have a core assumption that hard work **energizes** them: they experience effort as meaningful, energizing and sharpening. Others have a core assumption that hard work **drains** them: that effort in itself is a cost that depletes. The point is not that one group is "lying" and the other "right." The point is that these expectations can influence how the body mobilizes resources: - If you expect a demanding task to give you energy, you meet it with more curiosity, more persistence and less internal resistance. - If you expect it to deplete you, you meet it with more tension, more avoidance and higher subjective effort. Over time this can produce measurable differences in outcomes. The same workload can feel different, and that experience affects both how long you persist and how effective you are while doing it. The question then becomes: **Can we change how we perceive work to improve performance?** In practice it often comes down to working with the story you tell yourself: - "This will break me" can be replaced with "This will be demanding, but it can also build capacity." - "I can’t handle pressure" can be nuanced to "I can handle some pressure, and I can regulate it better with breaks and priorities." Such adjustments are not self-deception. They are a more precise calibration of expectations — away from absolute conclusions and toward flexible, learning-oriented assumptions. ## Placebo: the brain as a pharmacy The placebo effect is one of the clearest examples of how expectation affects the body. The core of placebo is not "imagining" symptoms away. It’s about the brain’s ability to modulate bodily processes — including pain, motor function, stress and symptom perception — based on what it expects. That is why people sometimes say the brain works like a "pharmacy": it can release the body’s own chemicals (for example endorphins and other neurochemicals) in response to the expectation of treatment and relief. This is well documented across areas, and a striking example is found in Parkinson’s disease. Some Parkinson’s patients can experience symptom relief from placebo. That doesn’t mean the disease is gone, but symptom burden and function can be influenced. The expectation of help appears to activate brain systems that can temporarily improve motor control or reduce symptom experience. An important point here is that **attitude toward medications can influence their effect.** If you expect strong improvement, you may get more effect (both from placebo and sometimes from active medicine). If you expect side effects and little benefit, you can in some cases experience more discomfort and less perceived effect. Again: this is not a moralizing call to "think correctly." It is a description of how expectation is an active ingredient in human experience. ## Expectations' effect on demanding tasks Imagine an experiment where people are given a demanding task and different expectations about how they will respond. Some are framed to expect the challenge to sharpen them, others are framed to expect it to exhaust them. What we often see in such contexts is that expectation affects: - how quickly people give up - how much discomfort they report - how well they perform - how focused they can remain A positive mindset then does not work like "magic," but as an **engine**: it makes it easier to mobilize effort and stay on course through friction. That does not mean everything becomes easy. It means you are more likely to interpret exertion as a sign that you are working — not a sign you are about to collapse. This shift is subtle but important: many interpret discomfort as danger. In reality discomfort is often a sign of growth, strain or learning. Sometimes discomfort is an important warning of boundary violation, but not always. Distinguishing between these is part of psychological maturity. ## Optimism with ground contact It is easy to misuse the expectation effect as a recipe for constant positivity. That is rarely helpful. Healthy optimism is not about denying pain, illness, loss or limits. It is about meeting difficulty with a basic belief that you can influence something: your choices, your response, your direction. Realistic optimism might sound like this: - "This is hard, but I can take one step at a time." - "I don’t know how it will turn out, but I can improve the odds by acting wisely." - "I can be afraid and brave at the same time." It is also important to recognize that some expectations are protective. If you have been disappointed many times, low expectations can feel safer. They can be a way to avoid pain. The problem is that they often also reduce life engagement. The task then is not to "force positivity," but to examine whether the expectation is updated or outdated. ## Relationships, self-image and quality of life Expectations color not only health and performance. They color relationships. If you expect others to reject you, you become more cautious, more testing, perhaps more withdrawn or more controlling. That can create distance that the other person notices. The distance confirms the expectation. If you expect you are not interesting, you may hold back more in conversations, share less, be less spontaneous. Again: less contact, more loneliness. Likewise, expectations about yourself shape self-esteem and quality of life: - "I never succeed" makes setbacks read as proof of incompetence. - "I can learn" makes setbacks read as information. The difference is not cosmetic. It changes how you recover from failure, how you tolerate uncertainty, and how much meaning you can extract from effort. ## Becoming curious about your own attitudes One of the most constructive approaches to the expectation effect is curiosity. Not to force "right" thoughts, but to make the operating system more flexible. A few questions can be useful: - What expectations do I have about my body, my health, my aging? - What expectations do I have about work and strain — does it energize me or drain me? - What expectations do I have about other people — do they want well for me or harm me? - What "evidence" do I use to support my expectations, and what evidence do I ignore? Simply seeing that expectations are expectations — not facts — can create a bit more room for action. ## Practical fine-tuning: from absolute to adjustable assumptions The expectation effect becomes particularly problematic when expectations become absolute and global: - "I always get sick." - "I can never handle pressure." - "People are not to be trusted." Such statements close possibilities. They make the future narrow. A more helpful alternative is to make expectations **specific, testable and flexible**: - "I tend to get tired during certain periods, and prioritizing sleep and breaks helps me." - "I can feel pressure as uncomfortable, but I can practice regulation and structure." - "Some people are unsafe, others are safe — I can learn to distinguish." This is not only language. It’s a different way of organizing experience that often produces less stress and more precise coping. ## Final reflection The expectation effect points to something deeply human: we do not live only in an outer world, but also in an inner model of the world. This model influences what we dare, what we avoid, how we interpret bodily signals, and how we meet others. Becca Levy’s research at Yale gives a powerful illustration of this by showing how attitudes toward aging relate to lifespan — with about a seven-year difference between the most positive and the most negative, even after accounting for several important background factors. David Robson’s *The Expectation Effect* collects a range of findings that point in the same direction: expectations can shape pain, performance and health, among other things, through the placebo effect, where the brain can release the body’s own chemicals and modulate symptoms based on what we believe will happen. At the same time it is crucial to keep nuance. Expectations are powerful, but not omnipotent. We do not need an ideology of constant positivity. We need a more flexible mental operating system: an ability to detect which assumptions guide us and to adjust them toward more realism, more hope and more room for action. Often the big changes happen in small shifts: From "this will go wrong" to "I don’t know, but I can influence something." From "aging is only loss" to "aging is also experience." From "hard work destroys me" to "hard work can build me — if I dose and recover wisely." Such expectations don’t remove life’s pain, but they can give better grip on life while it is lived. --- **Would you like to dive deeper into this topic?** This is a subject psychologist Sondre Risholm Liverød talks more about in the podcast episode of the same name. You can find the episode as part of the practice materials at [BeBalanced.ai](https://bebalanced.ai).