Wired for Habits

What Brain Science Says About Changing Your Days

Introduction

Think about the first hour of your day. You probably woke at about the same time as yesterday. You may have reached for your phone before you were fully awake. You walked to the bathroom, brushed your teeth in the same order as always, made the same drink in the same cup and perhaps looked out of the same window. If someone asked you to describe each step, you might struggle, because you did most of them without thinking. Your brain was running on habits.

Habits are the quiet machinery of our days. They decide a great deal of what we eat, how we move, how we spend our evenings, how we speak to the people we love and how we respond when we are tired or worried. Some habits serve us well. Others we would like to change, and many of us have tried, again and again, with mixed results. We make resolutions, start with enthusiasm and then, a few weeks later, find ourselves back where we began, wondering what is wrong with us.

This book looks at habits through the lens of brain science and psychology. Over the past century, and especially in recent decades, scientists have learned a great deal about how habits form in the brain, why they are so hard to change and what actually helps. Some of what they have learned is surprising. Some of it contradicts popular ideas, such as the claim that a habit takes exactly twenty-one days to form, or that changing a habit is simply a matter of willpower.

The good news is that much of this knowledge is practical. Once you understand how your brain builds habits, you can work with it rather than against it. You can design your surroundings, plan for difficult moments, start small, recover from slips and build days that look more like the days you want to live. You do not need to become a different person. You need to understand the person, and the brain, you already have.

How to Use This Book

There are fifteen chapters. Each begins with an ordinary scene: a person and a habit. Then it explains what brain science and psychology say about that part of habit, in plain language. After that come examples from many kinds of lives, practical steps, a short section on a common myth or a limit of the evidence, a short exercise and a summary.

Science is always changing, and some findings are much stronger than others. In this book, I try to tell you honestly how solid each idea is. When something is well established, I say so. When the evidence is mixed, or when scientists still disagree, I say that too. When a popular idea turns out to be a myth, I explain where it seems to have come from. I do not name individual researchers, and I do not quote numbers unless they are well known and helpful. You do not need to remember any of the scientific details to use the practical ideas.

You can read the chapters in order, because the early ones explain the basic machinery of habit, and the later ones build on it. Or you can go straight to the chapter that fits your situation. You may find it useful to choose one habit you would like to build or change, and to keep it in mind as you read. Many of the exercises work best with one specific habit in view.

A Note on Care

If you want to change habits related to your health, such as exercise, eating, sleep, alcohol or smoking, it is wise to talk to a doctor or another qualified professional about what is safe and suitable for you.

Some patterns of behaviour are more than ordinary habits. Addictions and compulsive behaviours involve the brain in different and more powerful ways, and they deserve professional support. If you feel that a habit is controlling your life, harming your health or hurting the people around you, please talk to a doctor or another qualified professional. If you ever feel that you might hurt yourself, or if you are in danger, contact a helpline or a medical facility right away, and in immediate danger call your local emergency number.

With that said, let us begin with a simple question: why does so much of your day run without you?

Chapter 1: Why So Much of Your Day Runs on Autopilot

The Drive to the Old Office

Valentina is thirty-six and recently changed jobs. For seven years, she worked at an insurance office on the north side of town. Two months ago, she started a new job as a manager at a logistics company on the east side. She is happy with the change. The work is more interesting, and her new colleagues are friendly.

Last Tuesday morning, Valentina got into her car, still thinking about a meeting she had that day. She drove out of her street, turned left at the bakery, took the ring road and followed the familiar route through three sets of traffic lights. She was planning what to say in the meeting, half listening to the radio and thinking about whether she had remembered to buy milk. Twenty minutes later, she pulled into a car park and looked up. She was outside her old office.

Valentina sat in the car for a moment, laughing and slightly alarmed. She had driven for twenty minutes, through traffic, past signs and turns, making dozens of small decisions, without being aware of any of them. Her hands had steered, her feet had pressed the pedals and her eyes had watched the road. But her conscious mind had been somewhere else entirely. Something inside her had simply taken over and driven the route it knew best.

She turned the car around and drove, carefully and consciously this time, to her new job. She arrived ten minutes late. All day, she kept thinking about what had happened. How could she drive so far without knowing it? What part of her had been in charge? And if that part of her could drive a car without her, what else was it doing that she did not notice?

Valentina's experience is extremely common. Most people who drive have had a similar moment. And it points to one of the most important facts about the human brain: a large part of what we do every day is not decided by careful, conscious thought. It is run by habits. This chapter explains what habits are, where they live in the brain and why the brain relies on them so much.

Two Ways the Brain Gets Things Done

Scientists who study behaviour often describe two broad ways in which the brain guides what we do. One is deliberate. You think about what you want, consider your options, choose an action and pay attention while you do it. This is how Valentina drove to her new job after turning around: carefully, thinking about each turn. Scientists call this goal-directed behaviour, because it is guided by a goal you have in mind.

The other way is automatic. A familiar situation triggers a familiar action, and the action runs more or less by itself, with little conscious thought. This is how Valentina drove to her old office: the situation of getting into her car in the morning triggered the route she had driven hundreds of times. Scientists call this habitual behaviour. A habit, in this scientific sense, is a learned link between a situation and a response, built up through repetition, so that the situation can trigger the response almost automatically.

These two ways of guiding behaviour seem to rely on partly different brain systems. Deliberate, goal-directed behaviour depends heavily on the prefrontal cortex, the part of the brain just behind the forehead, which is involved in planning, weighing options and holding goals in mind. Habitual behaviour depends heavily on a group of deep brain structures called the basal ganglia, and especially on a part of them called the striatum, which is involved in learning which actions to take in which situations.

This is, of course, a simplification. The brain is enormously complex, and these systems work together all the time, passing information back and forth. Scientists still debate many of the details. But the broad picture, that there is a more deliberate way of acting and a more automatic way, and that they rely on somewhat different brain circuits, is well supported by many years of research in animals and in people.

Valentina's drive shows both systems at work. When she started her new job, her deliberate system had to guide her along the new route. But her old route was stored as a strong habit, built up over seven years of driving it every morning. When her deliberate system was busy thinking about the meeting, the habit system took over, and it drove the route it knew.

What Animal Studies Revealed

Much of what we know about habits in the brain comes from studies with animals, especially rats. In a classic type of experiment, rats learn to press a lever to receive a small piece of food. At first, the rats press the lever because they want the food. Their behaviour is goal-directed. Researchers can test this by making the food less appealing, for example by letting the rats eat as much of it as they want beforehand. Rats that are pressing for the goal will press much less once the food is no longer wanted.

But something interesting happens when rats are trained for a long time. After many days of pressing the lever in the same situation, they keep pressing it even when the food has been made unappealing. Their behaviour has become a habit. It is now triggered by the situation, the box and the lever, rather than by the goal of getting food. Researchers have found that damage to different parts of the striatum can push rats toward one kind of behaviour or the other, which is part of the evidence that habits and goal-directed actions rely on partly different circuits (this description summarizes a long line of animal research).

Other animal studies have found that when an action sequence, such as running through a maze to a reward, is repeated many times, activity in parts of the basal ganglia changes. It becomes concentrated at the beginning and the end of the routine, as if the brain were marking where a learned "chunk" of behaviour starts and stops, while the middle runs more automatically. Scientists sometimes call this chunking. It helps explain why habits often feel like a single package: once the first step begins, the rest tends to follow.

Evidence in people points in the same direction. There is a famous case from the twentieth century of a man who, after brain surgery, could no longer form new memories of events. Each time he met someone, he did not remember meeting them before. Yet when he practised a difficult drawing task day after day, he got steadily better at it, even though he did not remember ever having done it. His ability to learn a new skill had survived, while his memory for events had not. This, and many later studies, suggested that the brain stores habits and skills in a different way from memories of events.

All of this helps explain Valentina's drive. Her old route had become a habit: a well-practised chunk of behaviour, triggered by the situation of starting her car in the morning, running without needing her goal or her attention. When her attention was elsewhere, the habit did exactly what it had been trained to do.

Why the Brain Loves Habits

If habits can take us to the wrong office, why does the brain rely on them so much? The answer is that habits are enormously useful. Deliberate thinking is slow and effortful. It uses a lot of our limited attention. If we had to think carefully about every action, every step of brushing our teeth, every movement of driving, every word of a familiar greeting, we would be exhausted before breakfast.

Habits free us from this burden. Once an action has become a habit, it can run with very little attention, leaving our conscious mind free for other things: planning a meeting, having a conversation, noticing something new. In this sense, habits are a gift. They let us do many things at once, and they let us save our limited attention for what really needs it.

Studies in which people keep diaries of their daily activities have suggested that a large share of what we do each day is repeated in much the same situation, day after day, often while we are thinking about something else. Researchers interpret this as a sign of how much of daily life runs on habit. The exact share is hard to measure and varies between people. But the general picture is clear: habits are not a small part of our lives. They are a large part of how we live.

This has two sides. On the positive side, it means that good habits can quietly carry us through our days, doing useful things without effort: washing hands, putting on a seatbelt, saying thank you, tidying as we go. On the negative side, it means that unhelpful habits can also run quietly, without our noticing, and that changing them is harder than simply deciding to. A habit does not need our permission to run. It only needs the situation that triggers it.

Understanding this is the first step toward working with habits rather than against them. It explains why good intentions often fail: intentions live in the deliberate system, but habits live in the automatic one, and when we are tired, busy or distracted, the automatic system tends to win. It also suggests where to look for change. If habits are triggered by situations, then changing the situations, as we will see in later chapters, is often more effective than simply trying harder.

Dumisani's Clean Hands

Dumisani is fifty-two and works in a factory that prepares packaged food. Hygiene is extremely important in his work. Every time he enters the production area, he must wash his hands thoroughly, following a set routine: wet, soap, scrub between the fingers, under the nails and around the thumbs, rinse, dry. When he started the job twenty years ago, he had to think about each step. He used to read the instructions on the wall above the sink.

Now, Dumisani washes his hands perfectly without thinking about it at all. He can talk with colleagues, plan his day or think about his family while his hands go through every step. The routine is triggered by the sink at the entrance to the production area. In fact, he says, he sometimes finds himself doing the full routine at home, at his own kitchen sink, to his wife's amusement.

Dumisani's handwashing is a good example of a helpful habit. It began as deliberate behaviour, guided by instructions and attention. Through thousands of repetitions in the same situation, it became automatic. Now it is reliable even on days when he is tired or distracted, which is exactly when hygiene mistakes are most likely. His habit protects the food, the customers and his own work.

Dumisani's story also shows that habits can be built deliberately. His employer designed the situation carefully: a sink placed at the entrance, clear instructions above it, a rule that everyone must wash before entering. These features made the behaviour easy to repeat in the same context, which is exactly what habits need. After enough repetition, the instructions on the wall were no longer necessary. The habit had moved from the deliberate system to the automatic one.

"When new workers start," Dumisani says, "I tell them: think about it now, every time, so that later you will not have to." Without knowing the brain science, he is describing the process exactly. Deliberate practice in a consistent situation builds an automatic habit, which then frees the mind for other things.

Élodie Learns to Drive

Élodie is seventeen and is learning to drive. In her first lessons, everything felt overwhelming. She had to think about the mirrors, the indicator, the pedals, the steering, the road, the other cars and her instructor's voice, all at once. After each lesson, she felt exhausted, as if she had been taking an exam for an hour. She could not imagine how anyone drove while talking or listening to music.

After about twenty lessons, something began to change. Élodie noticed that she no longer had to think about changing gear. Her hand and foot just did it at the right moments. A few lessons later, checking her mirrors before turning became automatic. She found that she could talk with her instructor while driving on familiar roads, which had been impossible at the start. Her lessons became less tiring.

Élodie's experience shows the shift from deliberate to automatic behaviour as it happens. At first, every part of driving required the prefrontal cortex: careful attention, planning, holding instructions in mind. With practice, parts of the task were handed over to the habit system, becoming automatic chunks. Each chunk that became automatic freed some of her attention for other things, such as watching the road ahead or talking.

Her instructor told her something important. "Some things should become automatic," he said, "like changing gear and checking mirrors. But never let the whole drive become automatic. Always keep part of your mind watching the road." He was describing exactly the danger that Valentina experienced: when a whole route becomes a habit, the deliberate system can drift away, and the habit may take you somewhere you did not intend to go.

Élodie passed her driving test a few months later. She still remembers how hard it was at the start. "It is strange," she says. "Now I do things without thinking that used to take all my concentration. It is like my brain learned to do them by itself." That is a good description of what the habit system does.

Rufus and the Half-Past-Five Alarm

Rufus is sixty-three and retired last year after thirty-five years as a postal sorting worker. For most of his working life, his shift started at seven, so he got up at half past five every morning. Now he is retired and can sleep as long as he likes. But every morning, at half past five, he wakes up. Without thinking, he goes downstairs, puts on the kettle, makes two slices of toast and stands at the kitchen window, just as he did for thirty-five years. Then he realizes that there is nowhere to go.

At first, Rufus found this funny. Then it began to frustrate him. He wanted to sleep later and enjoy slow mornings. But his body and brain kept running the old routine. He also noticed other habits that no longer fitted: he ate lunch at exactly eleven, as he had during his shift, and he felt restless in the afternoons, as if he should be doing something.

Rufus's habits had been built over decades, triggered by the same cues every day: the time, the dark morning, the kitchen, the kettle. They were deeply learned and very efficient. The problem was that his life had changed, but his habits had not. Like the rats who kept pressing the lever after the food was no longer wanted, his brain kept running a routine whose purpose had gone.

Rufus's daughter, who had read a little about habits, suggested that he did not need to fight his early waking. Instead, he could give it a new purpose. Rufus decided to keep getting up early, but to use the time differently. Instead of standing at the window waiting to go to work, he began to take a walk in the early morning, when the streets were quiet and the birds were singing. After a few weeks, the walk had become part of a new routine that he enjoyed.

"My body still wakes me at half past five," Rufus says. "But now it wakes me for something I want to do, not for something I used to have to do." Rufus's story shows that old habits can outlast their purpose, and that one way to deal with them is not to fight the cue, but to give it a new routine. We will see this idea again in later chapters.

Practical Steps: Noticing Your Autopilot

The first step is to notice when you are on autopilot. During the next few days, pay attention to moments when you realize that you have done something without being aware of it: driving a familiar route, reaching for your phone, eating a snack, saying something automatically. These are your habits at work. Notice them without judging yourself.

The second step is to recognize the value of your good habits. Look for the habits that serve you well: brushing your teeth, locking the door, greeting your family, doing your work carefully. These habits are working for you every day, often without your noticing. Appreciating them is a reminder that habits are not the enemy. They are tools.

The third step is to identify one habit you would like to change or build. Choose something specific: a habit you want to stop, such as checking your phone first thing in the morning, or a habit you want to build, such as taking a short walk after lunch. Keep this habit in mind as you read the rest of this book.

The fourth step is to notice the situation around the habit. For the habit you have chosen, ask: where does it happen? When? What happens just before it? Who is around? How do I feel? Habits are triggered by situations, so understanding the situation is the key to understanding the habit. We will explore this much more in the next chapter.

The fifth step is to remember that intentions alone are not enough. If you have tried to change a habit before by simply deciding to, and failed, it is not because you are weak. It is because intentions and habits rely on partly different systems in your brain. Changing a habit usually requires changing the situation, repeating a new behaviour many times and being patient. The rest of this book will explain how.

The sixth step is to keep part of your mind awake. As Élodie's driving instructor said, let the useful parts of life become automatic, but keep part of your attention on where you are going. Now and then, ask yourself whether your habits are still taking you where you want to go.

Habits Are Not Mindless, and Not Destiny

Two misunderstandings about habits are common. The first is that habits are mindless and therefore bad, the opposite of thoughtful living. This is not true. Many habits are intelligent solutions to the problem of limited attention. A surgeon's careful hand movements, a musician's fingers on the keys, a parent's automatic check that the stove is off: these are habits, and they are signs of skill and care, not mindlessness. The aim is not to get rid of habits, but to have habits that serve us.

The second misunderstanding is that habits are destiny: that once a habit has formed, we are stuck with it forever. This is also not true. The brain remains able to change throughout life, a property scientists call plasticity. Old habits can weaken, and new ones can form, at any age, though it may take time and patience. Rufus, at sixty-three, began to build a new morning habit within a few weeks. The rest of this book is about how such change happens.

It is also worth noting that the scientific picture in this chapter is simplified. The brain does not have one switch for habits and another for decisions. Many brain areas work together in complex ways, and scientists continue to study how. What is presented here is the broad outline that most researchers would recognize, not a complete map. When you read popular claims about "the habit part of the brain", it is wise to remember that the real picture is more complicated, and still being explored.

Finally, some repetitive behaviours are not ordinary habits. Compulsive behaviours that a person feels driven to repeat, even when they cause distress, and addictions to substances or activities involve the brain in different ways and can be very hard to change alone. If you are struggling with such a pattern, please talk to a doctor or another qualified professional.

A Short Exercise: A Day on Autopilot

This exercise helps you see how much of your day runs on habit. It takes a few minutes at the end of one day.

Choose an ordinary day, not a holiday or an unusual day. In the evening, take a page and write down, as well as you can remember, everything you did from waking up until the evening. Include small things: what you did first when you woke, how you got ready, what you ate and when, how you travelled, what you did during breaks, what you did when you got home.

Now go through the list and put a small mark next to each activity that you did in much the same way, at much the same time or place, as on most other days. These are likely to be habits. Put a different mark next to activities that required real thought and decision.

Look at the marks. How much of your day was habitual? Which habits served you well? Which would you like to change? Circle one habit you would like to build or change, and write a sentence about the situation in which it usually happens: where, when, after what, with whom and with what feeling.

Valentina did this exercise the evening after her drive to the old office. She was surprised to find that most of her morning, from waking to arriving at work, was habitual. She circled "checking work emails on my phone in bed as soon as I wake up", which she realized set a stressful tone for her whole day. Her sentence was: "In bed, as soon as the alarm goes off, phone on the bedside table, feeling half asleep and slightly anxious." That sentence became the starting point for a change we will return to later in this book.

Chapter Summary

Much of what we do each day is guided not by careful decisions but by habits: learned links between situations and responses, built through repetition, that run with little conscious thought. Brain science describes two broad ways of guiding behaviour, a deliberate, goal-directed way that relies heavily on the prefrontal cortex and a more automatic, habitual way that relies heavily on the basal ganglia, especially the striatum. Animal studies show that, with long training, behaviour shifts from goal-directed to habitual, continuing even when its reward is no longer wanted, and suggest that well-learned routines become "chunks". Habits save our limited attention, which is why the brain relies on them so much.

Valentina on the drive to her old office, Dumisani with his handwashing, Élodie learning to drive and Rufus waking at half past five all show habits at work: helpful, efficient and sometimes out of date. Habits are not mindless and not destiny. The brain can change throughout life. Compulsions and addictions are different from ordinary habits and deserve professional help.

In the next chapter, we will look more closely at the situations that trigger habits, which scientists call cues, and at how much they shape what we do.