How Emotions Are Made: The Secret Life of the Brain

by Lisa Feldman Barrett

at one point, one proposed marriage. Maria’s Namibian translator took the simple approach by explaining politely, in Otji-Herero, that Maria was “already married to another man with a very big gun.”

Not all cultures understand emotions as internal mental states. Himba and Hadza emotion concepts, for example, appear to be more focused on actions.

The Ifaluk of Micronesia consider emotions as transactions between people. To them, anger is not a feeling of rage, a scowl, a pounding fist, or a loud yelling voice, all within the skin of one person, but a situation in which two people are engaged in a script—a dance, if you will—around a common goal. In the Ifaluk view, anger does not “live” inside either participant.

Simple pleasant and unpleasant feelings come from an ongoing process inside you called interoception. Interoception is your brain’s representation of all sensations from your internal organs and tissues, the hormones in your blood, and your immune system. Think about what’s happening within your body right this second. Your insides are in motion. Your heart sends blood rushing through your veins and arteries. Your lungs fill and empty. Your stomach digests food. This interoceptive activity produces the spectrum of basic feeling from pleasant to unpleasant, from calm to jittery, and even completely neutral.

Your brain’s 86 billion neurons, which are connected into massive networks, never lie dormant awaiting a jump-start. Your neurons are always stimulating each other, sometimes millions at a time.

Your brain must figure out the meaning of those flashes and vibrations, and its main clues are your past experiences, which it constructs as simulations within its vast network of neural connections.

Predictions become simulations of sensations and movement. These simulations are compared to actual sensory input from the world. If they match, the predictions are correct and the simulation becomes your experience. If they don’t match, your brain must resolve the errors.

the brain can be flexible and change the prediction. In this situation, my motor neurons would adjust my body movements, and my sensory neurons would simulate different sensations, leading to further predictions involving prediction loops.

The brain’s second alternative is to be stubborn and stick with the original prediction. It filters the sensory input so it’s consistent with the prediction.

In a sense, your brain is wired for delusion: through continual prediction, you experience a world of your own creation that is held in check by the sensory world. Once your predictions are correct enough, they not only create your perception and action but also explain the meaning of your sensations. This is your brain’s default mode.

And marvelously, your brain does not just predict the future: it can imagine the future at will. As far as we know, no other animal brain can do that.

To simplify our discussion drastically, I’ll describe this network as having two general parts with distinct roles. One part is a set of brain regions that send predictions to the body to control its internal environment: speed up the heart, slow down breathing, release more cortisol, metabolize more glucose, and so on. We’ll call them your body-budgeting regions.* The second part is a region that represents sensations inside your body, called your primary interoceptive cortex.

In this manner, any event that significantly impacts your body budget becomes personally meaningful to you.

your brain predicts your body’s responses by drawing on prior experiences with similar situations and objects, even when you’re not physically active. And the consequence is interoceptive sensation.

people spend at least half their waking hours simulating rather than paying attention to the world around them, and this pure simulation strongly drives their feelings.

when you lose a close, loving relationship and feel physically ill about it, part of the reason is that your loved one is no longer helping to regulate your budget. You feel like you’ve lost a part of yourself because, in a sense, you have.

the simple feelings we discussed at the beginning of the chapter. Scientists call them affect.*

Affect is the general sense of feeling that you experience throughout each day. It is not emotion but a much simpler feeling with two features. The first is how pleasant or unpleasant you feel, which scientists call valence. The pleasantness of the sun on your skin, the deliciousness of your favorite food, and the discomfort of a stomachache or a pinch are all examples of affective valence. The second feature of affect is how calm or agitated you feel, which is called arousal. The energized feeling of anticipating good news, the jittery feeling after drinking too much coffee, the fatigue after a long run, and the weariness from lack of sleep are examples of high and low arousal.

Philosophers from the West and the East describe valence and arousal as basic features of human experience.

Your brain constantly uses past experience to predict which objects and events will impact your body budget, changing your affect. These objects and events are collectively your affective niche.

Hollywood is a $500 billion industry because people are willing to pay to see movies so that, for a few hours, they can travel within this affective map.

You don’t even have to open your eyes to have an affective adventure. When you daydream and have a large change in interoception, your brain will swirl with affect.

Imagine you are a judge presiding over a prisoner’s parole case. You are listening to the inmate’s story, hearing about his behavior in prison, and you have a bad feeling. If you agree to parole, he could hurt someone else. Your hunch is that you should keep him locked up. So you deny parole. Your bad feeling, which is unpleasant affect, seems like evidence that your judgment was correct. But could your affect have misled you? This exact situation was the subject of a 2011 study of judges. Scientists in Israel found that judges were significantly more likely to deny parole to a prisoner if the hearing was just before lunchtime. The judges experienced their interoceptive sensations not as hunger but as evidence for their parole decision. Immediately after lunch, the judges began granting paroles with their customary frequency.

The psychologist Gerald L. Clore has spent decades performing clever experiments to better understand how people make decisions every day based on gut feelings. This phenomenon is called affective realism, because we experience supposed facts about the world that are created in part by our feelings.

People employ affect as information, creating affective realism, throughout daily life. Food is “delicious” or “bland.” Paintings are “beautiful” or “ugly.” People are “nice” or “mean.” Women in certain cultures must wear scarves and wigs so as not to “tempt men” by showing a bit of hair. Sometimes affective realism is helpful, but it also shapes some of humanity’s most troubling problems. Enemies are “evil.” Women who are raped are perceived as “asking for it.” Victims of domestic violence are said to “bring it on themselves.”

Affective realism can also lead to tragic consequences. In July 2007, an American gunner aboard an Apache helicopter in Iraq mistakenly killed a group of eleven unarmed people, including several Reuters photojournalists. The soldier had misjudged a journalist’s camera to be a gun. One explanation for this incident is that affective realism caused the soldier, in the heat of the moment, to imbue a neutral object (a camera) with unpleasant valence. Every day, soldiers must make quick decisions about other people, whether they are embedded in a unit during wartime, on a peacekeeping mission, negotiating in a cross-cultural setting, or collaborating with unit members on a stateside base. These quick judgments are extremely difficult to negotiate, especially in such high-stakes, high-arousal settings where errors are often made at the expense of someone’s life.

People like to say that seeing is believing, but affective realism demonstrates that believing is seeing.

What happens next? Maybe a snake slithers out from the brush. In this case, the sensory input matches your predictions and you run. Or perhaps no snake is present—the leaves were just rustled by the wind—but you see a snake anyway. That’s affective realism. Now consider the third possibility: there is no snake, and you don’t see a snake. In this case, your visual predictions of a snake are corrected quickly; however, your interoceptive predictions are not.

In short, you feel what your brain believes. Affect primarily comes from prediction.

Everything you feel is based on prediction from your knowledge and past experience. You are truly an architect of your experience. Believing is feeling.

You might think that in everyday life, the things you see and hear influence what you feel, but it’s mostly the other way around: that what you feel alters your sight and hearing. Interoception in the moment is more influential to perception, and how you act, than the outside world is.

Antonio Damasio, in his bestseller Descartes’ Error, observes that a mind requires passion (what we would call affect) for wisdom.

The science of economics used to employ a concept called the rational economic person (homo economicus), who controls his or her emotions to make reasoned economic judgments. This concept was a foundation of Western economic theory, and though it has fallen out of favor among academic economists, it has continued to guide economic practice.

An economic model at the foundation of the U.S. economy—some might say the global economy—is rooted in a neural fairy tale.

Every economic crisis in the last thirty years has been related, at least in some part, to the rational economic person model. According to journalist Jeff Madrick, author of Seven Bad Ideas: How Mainstream Economists Have Damaged America and the World, several of economists’ most fundamental ideas caused a series of financial crises leading up to the Great Recession.

You cannot overcome emotion through rational thinking, because the state of your body budget is the basis for every thought and perception you have, so interoception and affect are built into every moment. Even when you experience yourself as rational, your body budget and its links to affect are there, lurking beneath the surface.

This origin myth is so strongly held that scientists even created a model of the brain based on it. The model begins with ancient subcortical circuits for basic survival, which we allegedly inherited from reptiles. Sitting atop those circuits is an alleged emotion system, known as the “limbic system,” that we supposedly inherited from early mammals. And wrapped around the so-called limbic system, like icing on an already-baked cake, is our allegedly rational and uniquely human cortex. This illusory arrangement of layers, which is sometimes called the “triune brain,” remains one of the most successful misconceptions in human biology. Carl Sagan popularized it in The Dragons of Eden, his bestselling (some would say largely fictional) account of how human intelligence evolved. Daniel Goleman employed it in his bestseller Emotional Intelligence.

So how do brains evolve? They reorganize as they expand, like companies do, to keep themselves efficient and nimble.

Every thought, memory, perception, or emotion that you construct includes something about the state of your body: a little piece of interoception. A visual prediction, for example, doesn’t just answer the question, “What did I see last time I was in this situation?” It answers, “What did I see last time I was in this situation when my body was in this state?”

From the perspective of your brain, anything in your affective niche could potentially influence your body budget, and nothing else in the universe matters. That means, in effect, that you construct the environment in which you live.

Interoception, as a fundamental part of the predictive process, is a key ingredient of emotion. However, interoception alone cannot explain emotion. An emotion category like anger or sadness is far more complex than a simple feeling of unpleasantness and arousal.

Affect alone also doesn’t explain how we construct our own experiences of sadness, nor how one instance of sadness differs from another. Nor does affect tell you what sensations mean or what to do about them.

You must make the affect meaningful so your brain can execute a more specific action. One way to make meaning is to construct an instance of emotion.

in nature, a rainbow has no stripes—it’s a continuous spectrum of light, with wavelengths that range from approximately 400 to 750 nanometers. This spectrum has no borders or bands of any kind. Why do you and I see stripes? Because we have mental concepts for colors like “Red,” “Orange,” and “Yellow.” Your brain automatically uses these concepts to group together the wavelengths in certain ranges of the spectrum, categorizing them as the same color. Your brain downplays the variations within each color category and magnifies the differences between the categories, causing you to perceive bands of color.

Human speech also is continuous—a stream of sound—yet when you listen to your native language, you hear discrete words. How does that happen? Once again, you use concepts to categorize the continuous input.

All sensory information is a massive, constantly changing puzzle for your brain to solve. The objects you see, the sounds you hear, the odors you smell, the touches you feel, the flavors you taste, and the interoceptive sensations you experience as aches and pains and affect . . . they all involve continuous sensory signals that are highly variable and ambiguous as they reach your brain. Your brain’s job is to predict them before they arrive, fill in missing details, and find regularities where possible, so that you experience a world of objects, people, music, and events, not the “blooming, buzzing confusion” that is really out there.6 To achieve this magnificent feat, your brain employs concepts to make the sensory signals meaningful, creating an explanation for where they came from, what they refer to in the world, and how to act on them.

Your perceptions are so vivid and immediate that they compel you to believe that you experience the world as it is, when you actually experience a world of your own construction. Much of what you experience as the outside world begins inside your head.

To see the real power of goal-based concepts, consider a purely mental concept such as “Things That Can Protect You from Stinging Insects.” Instances of the category are remarkably diverse: a flyswatter, a beekeeper’s suit, a house, a Maserati, a large trash can, a vacation in Antarctica, a calm demeanor, even a university degree in entomology. They share no perceptual features. This category is clearly and entirely a construction of the human mind.

Goal-based concepts therefore free you from the shackles of physical appearance. When you walk into an entirely new situation, you don’t experience it based solely on how things look, sound, or smell. You experience it based on your goal.

what’s happening in your brain when you categorize? You are not finding similarities in the world but creating them.