Every day we all engage in a surprising number of habitual behaviors. Many of them, from brushing our teeth to driving a familiar route, simply allow us to do certain things on autopilot so that our brains are not overtaxed by concentrating on each brushstroke and countless tiny adjustments of the steering wheel. Other habits, such as jogging, may help keep us healthy. Regularly popping treats from the candy dish may not. And habits that wander into the territory of compulsions or addictions, such as overeating or smoking, can threaten our existence.
Even though habits are a big part of our lives, scientists have had a hard time pinning down how the brain converts a new behavior into a routine. Without that knowledge, specialists have had difficulty helping people break bad habits, whether with medicines or other therapies.