The Power of Habit: Why We Do What We Do in Life and Business

The first question that I considered in reviewing this best-selling new book was why a work about habits would be relevant to the readers of a journal about cognitive and behavioral neurology. In the course of reading the book, I came to appreciate that habits and habitual behavior are important to cognitive neurologists and neuropsychiatrists. Perhaps the most obvious link is the chapter on Eugene Pauly, a man with amnesia caused by herpes simplex encephalitis, who was studied by Dr Larry Squire. Like the well-known amnesic patient H.M., Eugene had a virtually complete loss of short-term memory, but to some extent his habits seemed to compensate for his deficits. He took walks every day and did not get lost, although he remembered nothing of the walks afterward, and could not draw a map of his block. When asked where the kitchen was in his home, he had no idea, but when asked what he would do if he was hungry, he effortlessly walked into the kitchen and got a jar of nuts. Habit patterns, entrained in the basal ganglia, helped him carry out normal activities of daily living, without any conscious memory of what he was doing. Author Charles Duhigg, a reporter for The New York Times, brings the expected reportorial detail to his vast array of examples of how habits affect our daily lives. His thesis for the book is that many human activities depend on habits that become unconscious routines, carried out by the basal ganglia, without any conscious or cortical direction. He defines a “habit loop” as a sequence of cue, routine, and reward. Every habit loop has a reward that continues to reinforce the habit. Pepsodent toothpaste became popular because it was claimed to remove an unsightly “film” from teeth, but the habit of toothbrushing did not become widespread until users came to depend on a “reward” in the form of a cool, tingling feeling caused by additives that had nothing to do with the toothpaste’s beneficial effects. This pleasant feeling became a habitual expectation associated with brushing. Similarly, Febreze air fresheners did not become a popular way to remove bad odors until the manufacturers added a fragrance. The fragrance created a habit loop with the expected reward that the bathroom or car would smell good. Implicit in these habit loops is a craving that develops for the reward, whether it is the tingling feeling from the toothpaste or the pleasant fragrance of the air freshener. Duhigg discusses other kinds of habit loops: the habits that National Football League coach Tony Dungy developed in his defensive line, habits so strong that when the players acted instinctively, they responded faster than they could through conscious intent; the success of Alcoholics Anonymous in getting habitual drinkers to stop drinking; strategies to change habits in compulsive nail-biters and gamblers; the success of Paul O’Neill in leading the manufacturing company Alcoa and several government agencies; and the swimming victories of Michael Phelps. The only issue that I have with these examples is that not all of them clearly involve habits. In fact, Paul O’Neill’s success was based partly on his encouraging lower-level employees to call him with suggestions. These suggestions transformed the company through conscious effort, not through habit. Duhigg devotes a chapter to Starbucks, whose coffee stores emphasize habitually treating people politely and efficiently. The company profits from instilling these habits, not only for customers, who spend more money than seems reasonable for each cup of coffee, but also for the employees. Another chapter discusses how medical mistakes, such as occurred recently at Rhode Island Hospital, can be prevented by surgical staffs’ habitually using checklists and time-outs before starting operations, and how a loss of safety practice habits led to a fatal fire in the London Underground. Another example is Target stores, which promote habitual shopping patterns by sending coupons that are individually geared to each customer’s needs. Target gathers information such as which customers are pregnant and likely to have children in the near future. The company then inserts coupons for baby paraphernalia randomly among its advertisements, to avoid suspicion that it is “spying” on its customers. Expanding his main thesis, Duhigg discusses how the habits of societies explain the successes of Rosa Parks and the Montgomery bus boycott, and of Pastor Rick Warren and his creation of the Saddleback Church in California. Another section of the book concerns criminal responsibility for habits. One unfortunate man accidentally strangled his wife during a violent dream, related to his lifelong habitual sleepwalking (though I think that this man had REM sleep behavior disorder rather than sleepwalking, and a sleep expert might not want to call it a “habit”). The man was acquitted of murder because he was not consciously responsible for his habitdriven behavior. Duhigg contrasts this case with that of a woman who sued a casino for giving her rewards and perks to induce her to continue her habitual gambling until she drove her family into bankruptcy. Though habit-driven, her behavior was conscious; she could have tried to change her habits. Because she yielded voluntarily, she lost her legal case. In the final section of the book, Duhigg teaches readers how to The author declares no conflicts of interest. BOOK REVIEW