Emotional Design

by Donald A. Norman

  The problem is that we still let logic make decisions for us, even though our emotions are telling us otherwise. Business has come to be ruled by logical, rational decision makers, by business models and accountants, with no room for emotion. Pity!

  We cognitive scientists now understand that emotion is a necessary part of life, affecting how you feel, how you behave, and how you think. Indeed, emotion makes you smart. That’s the lesson of my current research. Without emotions, your decision-making ability would be impaired. Emotion is always passing judgments, presenting you with immediate information about the world: here is potential danger, there is potential comfort; this is nice, that bad. One of the ways by which emotions work is through neurochemicals that bathe particular brain centers and modify perception, decision making, and behavior. These neurochemicals change the parameters of thought.

  The surprise is that we now have evidence that aesthetically pleasing objects enable you to work better. As I shall demonstrate, products and systems that make you feel good are easier to deal with and produce more harmonious results. When you wash and polish your car, doesn’t it seem to drive better? When you bathe and dress up in clean, fancy clothes, don’t you feel better? And when you use a wonderful, well-balanced, aesthetically pleasing garden or woodworking tool, tennis racket or pair of skis, don’t you perform better?

  Before I go on, let me interject a technical comment: I am talking here about affect, not just emotion. A major theme of this book is that much of human behavior is subconscious, beneath conscious awareness. Consciousness comes late, both in evolution and also in the way the brain processes information; many judgments have already been determined before they reach consciousness. Both affect and cognition are information-processing systems, but they have different functions. The affective system makes judgments and quickly helps you determine which things in the environment are dangerous or safe, good or bad. The cognitive system interprets and makes sense of the world. Affect is the general term for the judgmental system, whether conscious or subconscious. Emotion is the conscious experience of affect, complete with attribution of its cause and identification of its object. The queasy, uneasy feeling you might experience, without knowing why, is affect. Anger at Harry, the used-car salesman, who overcharged you for an unsatisfactory vehicle, is emotion. You are angry at something—Harry—for a reason. Note that cognition and affect influence one another: some emotions and affective states are driven by cognition, while affect often impacts cognition.

  Let’s look at a simple example. Imagine a long and narrow plank ten meters long and one meter wide. Place it on the ground. Can you walk on it? Of course. You can jump up and down, dance, and even walk along with your eyes shut. Now prop the plank up so that it is three meters off the ground. Can you walk on it? Yes, although you proceed more carefully.

  What if the plank were a hundred meters in the air? Most of us wouldn’t dare go near it, even though the act of walking along it and maintaining balance should be no more difficult than when the plank is on the ground. How can a simple task suddenly become so difficult? The reflective part of your mind can rationalize that the plank is just as easy to walk on at a height as on the ground, but the automatic, lower visceral level controls your behavior. For most people, the visceral level wins: fear dominates. You may try to justify your fear by stating that the plank might break, or that, because it is windy, you might be blown off. But all this conscious rationalization comes after the fact, after the affective system has released its chemicals. The affective system works independently of conscious thought.

  Finally, affect and emotion are crucial for everyday decision making. The neuroscientist Antonio Damasio studied people who were perfectly normal in every way except for brain injuries that impaired their emotional systems. As a result, despite their appearance of normality, they were unable to make decisions or function effectively in the world. While they could describe exactly how they should have been functioning, they couldn’t determine where to live, what to eat, and what products to buy and use. This finding contradicts the common belief that decision making is the heart of rational, logical thought. But modern research shows that the affective system provides critical assistance to your decision making by helping you make rapid selections between good and bad, reducing the number of things to be considered.

  People without emotions, as in Damasio’s study, are often unable to choose between alternatives, especially if each choice appears equally valid. Do you want to come in for your appointment on Monday or Tuesday? Do you want rice or baked potato with your food? Simple choices? Yes, perhaps too simple: there is no rational way to decide. This is where affect is useful. Most of us just decide on something, but if asked why, often don’t know: “I just felt like it,” one might reply. A decision has to “feel good,” or else it is rejected, and such feeling is an expression of emotion.

  The emotional system is also tightly coupled with behavior, preparing the body to respond appropriately to a given situation. This is why you feel tense and edgy when anxious. The “queasy” or “knotted” feelings in your gut are not imaginary—they are real manifestations of the way that emotions control your muscle systems and, yes, even your digestive system. Thus, pleasant tastes and smells cause you to salivate, to inhale and ingest. Unpleasant things cause the muscles to tense as preparation for a response. A bad taste causes the mouth to pucker, food to be spit out, the stomach muscles to contract. All of these reactions are part of the experience of emotion. We literally feel good or bad, relaxed or tense. Emotions are judgmental, and prepare the body accordingly. Your conscious, cognitive self observes those changes. Next time you feel good or bad about something, but don’t know why, listen to your body, to the wisdom of its affective system.

  Just as emotions are critical to human behavior, they are equally critical for intelligent machines, especially autonomous machines of the future that will help people in their daily activities. Robots, to be successful, will have to have emotions (a topic I discuss in more detail in chapter 6). Not necessarily the same as human emotions, these will be emotions nonetheless, ones tailored to the needs and requirements of a robot. Furthermore, the machines and products of the future may be able to sense human emotions and respond accordingly. Soothe you when you are upset, humor you, console you, play with you.

  As I’ve said, cognition interprets and understands the world around you, while emotions allow you to make quick decisions about it. Usually, you react emotionally to a situation before you assess it cognitively, since survival is more important than understanding. But sometimes cognition comes first. One of the powers of the human mind is its ability to dream, to imagine, and to plan for the future. In this creative soaring of the mind, thought and cognition unleash emotion, and are in turn changed themselves. To explain how this comes about, let me now turn to the science of affect and emotion.

  PART ONE

  The Meaning of Things

  CHAPTER ONE

  Attractive Things Work Better

  NOAM TRACTINSKY, AN ISRAELI SCIENTIST, WAS puzzled. Attractive things certainly should be preferred over ugly ones, but why would they work better? Yet in the early 1990s, two Japanese researchers, Masaaki Kurosu and Kaori Kashimura, claimed just that. They studied different layouts of controls for ATMs, automated teller machines that allow us to perform simple banking tasks any time of the day or night. All versions of the ATMs were identical in function, the number of buttons, and how they operated, but some had the buttons and screens arranged attractively, the others unattractively. Surprise! The Japanese found that the attractive ones were perceived to be easier to use.

  Tractinsky was suspicious. Maybe the experiment had flaws. Or perhaps the result could be true of Japanese, but certainly not of Israelis. “Clearly,” said Tractinsky, “aesthetic preferences are culturally dependent.” Moreover, he continued, “Japanese culture is known for its aesthetic tradition,” but Israelis? Nah, Israelis are action-oriented—they don’t care about beauty.
So Tractinsky redid the experiment. He got the ATM layouts from Kurosu and Kashimura, translated them from Japanese into Hebrew, and designed a new experiment, with rigorous methodological controls. Not only did he replicate the Japanese findings, but—contrary to his belief that usability and aesthetics “were not expected to correlate”—the results were stronger in Israel than in Japan. Tractinsky was so surprised that he put that phrase “were not expected” in italics, an unusual thing to do in a scientific paper, but appropriate, he felt, given the unexpected conclusion.

  In the early 1900s, Herbert Read, who wrote numerous books on art and aesthetics, stated, “it requires a somewhat mystical theory of aesthetics to find any necessary connection between beauty and function,” and that belief is still common today. How could aesthetics affect how easy something is to use? I had just started a research project examining the interaction of affect, behavior, and cognition, but Tractinsky’s results bothered me—I couldn’t explain them. Still, they were intriguing, and they supported my own personal experiences, some of which I described in the prologue. As I pondered the experimental results, I realized they fit with the new framework that my research collaborators and I were constructing as well as with new findings in the study of affect and emotion. Emotions, we now know, change the way the human mind solves problems—the emotional system changes how the cognitive system operates. So, if aesthetics would change our emotional state, that would explain the mystery. Let me explain.

  Until recently, emotion was an ill-explored part of human psychology. Some people thought it an evolutionary leftover from our animal origins. Most thought of emotions as a problem to be overcome by rational, logical thinking. And most of the research focused upon negative emotions such as stress, fear, anxiety, and anger. Modern work has completely reversed this view. Science now knows that evolutionarily more advanced animals are more emotional than primitive ones, the human being the most emotional of all. Moreover, emotions play a critical role in daily lives, helping assess situations as good or bad, safe or dangerous. As I discussed in the prologue, emotions aid in decision making. Positive emotions are as important as negative ones—positive emotions are critical to learning, curiosity, and creative thought, and today research is turning toward this dimension. One finding particularly intrigued me: The psychologist Alice Isen and her colleagues have shown that being happy broadens the thought processes and facilitates creative thinking. Isen discovered that when people were asked to solve difficult problems, ones that required unusual “out of the box” thinking, they did much better when they had just been given a small gift—not much of a gift, but enough to make them feel good. When you feel good, Isen discovered, you are better at brainstorming, at examining multiple alternatives. And it doesn’t take much to make people feel good. All Isen had to do was ask people to watch a few minutes of a comedy film or receive a small bag of candy.

  We have long known that when people are anxious they tend to narrow their thought processes, concentrating upon aspects directly relevant to a problem. This is a useful strategy in escaping from danger, but not in thinking of imaginative new approaches to a problem. Isen’s results show that when people are relaxed and happy, their thought processes expand, becoming more creative, more imaginative.

  These and related findings suggest the role of aesthetics in product design: attractive things make people feel good, which in turn makes them think more creatively. How does that make something easier to use? Simple, by making it easier for people to find solutions to the problems they encounter. With most products, if the first thing you try fails to produce the desired result, the most natural response is to try again, only with more effort. In today’s world of computer-controlled products, doing the same operation over again is very unlikely to yield better results. The correct response is to look for alternative solutions. The tendency to repeat the same operation over again is especially likely for those who are anxious or tense. This state of negative affect leads people to focus upon the problematic details, and if this strategy fails to provide a solution, they get even more tense, more anxious, and increase their concentration upon those troublesome details. Contrast this behavior with those who are in a positive emotional state, but encountering the same problem. These people are apt to look around for alternative approaches, which is very likely to lead to a satisfying end. Afterward, the tense and anxious people will complain about the difficulties whereas the relaxed, happy ones will probably not even remember them. In other words, happy people are more effective in finding alternative solutions and, as a result, are tolerant of minor difficulties. Herbert Read thought we would need a mystical theory to connect beauty and function. Well, it took one hundred years, but today we have that theory, one based in biology, neuroscience, and psychology, not mysticism.

  Human beings have evolved over millions of years to function effectively in the rich and complex environment of the world. Our perceptual systems, our limbs, the motor system—which means the control of all our muscles—everything has evolved to make us function better in the world. Affect, emotion, and cognition have also evolved to interact with and complement one another. Cognition interprets the world, leading to increased understanding and knowledge. Affect, which includes emotion, is a system of judging what’s good or bad, safe or dangerous. It makes value judgments, the better to survive.

  The affective system also controls the muscles of the body and, through chemical neurotransmitters, changes how the brain functions. The muscle actions get us ready to respond, but they also serve as signals to others we encounter, which provides yet another powerful role of emotion as communication: our body posture and facial expression give others clues to our emotional state. Cognition and affect, understanding and evaluation—together they form a powerful team.

  Three Levels of Processing: Visceral, Behavioral, and Reflective

  Human beings are, of course, the most complex of all animals, with accordingly complex brain structures. A lot of preferences are present at birth, part of the body’s basic protective mechanisms. But we also have powerful brain mechanisms for accomplishing things, for creating, and for acting. We can be skilled artists, musicians, athletes, writers, or carpenters. All this requires a much more complex brain structure than is involved in automatic responses to the world. And finally, unique among animals, we have language and art, humor and music. We are conscious of our role in the world and we can reflect upon past experiences, the better to learn; toward the future, the better to be prepared; and inwardly, the better to deal with current activities.

  My studies of emotion, conducted with my colleagues Andrew Ortony and William Revelle, professors in the Psychology Department at Northwestern University, suggest that these human attributes result from three different levels of the brain: the automatic, prewired layer, called the visceral level; the part that contains the brain processes that control everyday behavior, known as the behavioral level; and the contemplative part of the brain, or the reflective level. Each level plays a different role in the total functioning of people. And, as I discuss in detail in chapter 3, each level requires a different style of design.

  The three levels in part reflect the biological origins of the brain, starting with primitive one-celled organisms and slowly evolving to more complex animals, to the vertebrates, the mammals, and finally, apes and humans. For simple animals, life is a continuing set of threats and opportunities, and an animal must learn how to respond appropriately to each. The basic brain circuits, then, are really response mechanisms: analyze a situation and respond. This system is tightly coupled to the animal’s muscles. If something is bad or dangerous, the muscles tense in preparation for running, attacking, or freezing. If something is good or desirable, the animal can relax and take advantage of the situation. As evolution continued, the circuits for analyzing and responding improved and became more sophisticated. Put a section of wire mesh fence between an animal and some desirable food: a chicken is likely to be stuck forever, straining at the fence,
but unable to get to the food; a dog simply runs around it. Human beings have an even more developed set of brain structures. They can reflect upon their experiences and communicate them to others. Thus, not only do we walk around fences to get to our goals, but we can then think back about the experience—reflect upon it—and decide to move the fence or the food, so we don’t have to walk around the next time. We can also tell other people about the problem, so they will know what to do even before they get there.

  FIGURE 1.1 Three levels of processing: Visceral, Behavioral, and Reflective.

  The visceral level is fast: it makes rapid judgments of what is good or bad, safe or dangerous, and sends appropriate signals to the muscles (the motor system) and alerts the rest of the brain. This is the start of affective processing. These are biologically determined and can be inhibited or enhanced through control signals from above. The behavioral level is the site of most human behavior. Its actions can be enhanced or inhibited by the reflective layer and, in turn, it can enhance or inhibit the visceral layer. The highest layer is that of reflective thought. Note that it does not have direct access either to sensory input or to the control of behavior. Instead it watches over, reflects upon, and tries to bias the behavioral level.

  (Modified from a figure by Daniel Russell for Norman, Ortony, & Russell, 2003.)

  Animals such as lizards operate primarily at the visceral level. This is the level of fixed routines, where the brain analyzes the world and responds. Dogs and other mammals, however, have a higher level of analysis, the behavioral level, with a complex and powerful brain that can analyze a situation and alter behavior accordingly. The behavioral level in human beings is especially valuable for well-learned, routine operations. This is where the skilled performer excels.