How Habits Work
A Every day we carry out hundreds of actions without thinking about them. We brush our teeth, lock the door and take the same route to work almost automatically. These actions are habits, and they are useful because they save mental effort. When the brain does not need to decide each small step, it is free to deal with new problems, plans and conversations.
B Researchers describe a habit as a loop with three parts. First there is a cue, which is a signal such as a time of day, a place or a feeling. Then comes the routine, the action itself. Finally there is a reward, which is usually small, such as a moment of pleasure or a feeling of relief. A phone that buzzes is a cue, checking the message is the routine, and the small pleasure of reading it is the reward. After many repetitions, the brain links the cue to the reward, and the action follows without effort.
C Habits are closely tied to the places and the situations in which they were formed. A person who always eats a snack in front of the television may find that the urge disappears on holiday, away from the sofa. For this reason, a change of home, school or job can break old habits, because the cues are no longer there. Psychologists suggest that these moments are a good time to begin new routines, since there is no old pattern to fight.
D There is a popular belief that it takes twenty-one days to form a habit. Research does not support such a fixed number. Studies of volunteers show that the time varies from a few weeks to many months, and that simple actions, such as drinking a glass of water after breakfast, become automatic faster than complex ones, such as exercising for an hour. The same studies found that missing a single day did not ruin the process, as long as the person returned to the routine the next day.
E Several methods help to build a new habit. One is to start with an action so small that it feels almost too easy, such as reading one page a day. Another is to attach the new action to an existing habit, for example by reading one page straight after making tea. A third is to make the cue obvious, by leaving the book on the pillow, and a fourth is to give a reward at once, so that the brain links the action with a pleasant result.
F Breaking an unwanted habit is harder than starting a good one. Simply trying to stop rarely works for long, because the cue is still there and the brain still expects the reward. A better method is to keep the cue and replace the routine with a different one that gives a similar reward, such as a short walk in place of a snack. It also helps to make the bad habit harder to do, by putting the biscuits on a high shelf. Willpower is weakest when a person is tired, so plans that rely on it alone often fail.