03/18/2010 05:12 am ET | Updated Nov 17, 2011

How Habits Can Make Or Break Us

We've all done it: We leave the house with the intention of driving to the dry cleaners, and then minutes later find that we forgot to make the right turn and instead ended up at the office. The universal nature of this kind of "auto-pilot" experience shows just how powerful habits are in our lives. By knowing more about where habits come from and how they develop, we can learn to both take advantage of them and manage their impact in our daily lives.

When we do something repeatedly, like driving the same route to work, our brains adapt by developing habits. Although this can sometimes lead us astray, in general it's a good thing: We don't want to waste brain power making the same choices every day when the answer is (almost) always the same. Think about it: Would you want to have to consciously decide which pedal to press every time you come to a stop sign? However, habits are a double-edged sword. Unless we can override them when we need to, such as when we need to stop at the cleaners rather than going to work, we become "creatures of habit" in the worst sense of the term.

Neuroscience research has told us a great deal about where habits come from and how they get overridden. What we know is that the basal ganglia, an evolutionarily ancient set of brain areas, are critical for learning habits. The basal ganglia are generally involved in learning which actions to take in which situations, based on the outcomes of those actions. For example, when we learn that we should press the rightward pedal to move our car forward and the leftward pedal to stop, it is the basal ganglia that are responsible for learning this. Our old friend dopamine is also an important player in learning which actions to choose, since it provides our brain with a signal about whether our choices have been successful or not, and modulates our brain's ability to change itself (as I discussed in my previous post).

What seems to happen when we develop habits is that the processes that are usually involved in choosing an action (such as which way to turn at each intersection on the way to work) get short-circuited, so that instead of thinking about which action is the best one to choose based on their possible outcomes, we simply do what we have done before. One interesting consequence of this is that these habits will persist even if they no longer produce the desired result. My favorite example is the "Get New Mail" button in my email program. For a long time, my mail program was set to only check my mail when I pressed the "Get New Mail" button. Later, I switched it to automatically get any new mail every minute. This meant that pressing the "Get New Mail" button almost never actually got any new mail. However, this didn't stop me from pressing the "Get New Mail" button, and even years later I sometimes find myself mindlessly pressing it!

The persistence of habits can be a blessing or a curse. At their worst, they can result in a life-long struggle against addictions or other bad habits; it's no surprise that addictive drugs hijack the same brain systems that are involved in learning everyday habits. But we can also use habits to help shape our own lives in a better direction.

When we decide that we want to add a new routine in our life (be it adopting a new exercise program or shopping in a more price-conscious way at the grocery store), the most important thing is consistency. Habits develop when we do the same things in the same context repeatedly, so if we want to develop a new habit, it is important both that we do it often but also that we do it as consistently as possible. As an example, I am trying to get into the habit of looking at my calendar and to-do list every morning, to make sure that I don't miss any important meetings or obligations. At first, it took a lot of mental energy to remember to look at it every morning, but over time it's become part of my routine that I don't have to even think about any more.