Two interesting studies in a paper in the November, 2011 issue of and Social Psychology Bulletin by David Neal, Wendy Wood, Megju Wu, and David Kurlander demonstrate both the power of habits and a way to disrupt those habits.

In the first study, one group of participants was recruited before going to watch a movie at a theater. They were told they were going to watch some movie trailers to give their opinions about them. Participants were given water and popcorn and they watched 15 minutes of trailers. After leaving the theater, the participants rated how much they liked the popcorn and how frequently they eat popcorn when going to the movies.

The interesting manipulation in this study was that half of the participants got fresh popcorn that had just been popped, while the other half got stale popcorn that had been popped a week before the study. After the study, those who got the fresh popcorn rated it as tastier than those who got the stale popcorn.

People who don't have the habit to eat popcorn at the movies at far more of it when it was fresh than when it was stale. However, those who routinely eat popcorn at the movies at most of the popcorn regardless of whether it was fresh or stale. That is, having the habit to eat popcorn led people to eat, even when they were eating lousy pocorn.

The habit is specific, though. Another group of participants was recruited to watch and rate music videos in a meeting room. That group was also given popcorn that was either fresh or stale. Everyone in this context ate less if they got stale popcorn than if they got fresh popcorn, even if they have the habit to eat popcorn at the movies.

The last study in this paper demonstrated that you can interfere with people's habits. Habits are often specific in the actions that are used to carry them out. Your habit in the car to press the accelerator and the brake is related to the movement of your leg.

With popcorn, people often have the habit to eat with one hand or the other. Most right-handers eat their popcorn with their right hand, for example. In another study, people were recruited at a theater to watch movie trailers. They were given a box of popcorn that had a handle they had to slide over one hand. They were either told to slide it over their dominant hand or over their nondominant hand. So, if you're right-handed and you normally eat popcorn with your right hand, then if you are forced to hold the popcorn box with your right hand, your habitual way of eating is disrupted.

As with the previous study, people who had the habit to eat popcorn at the movies, and who could eat mindlessly with their dominant hands ate a lot of popcorn regardless of whether it was fresh or stale. But, those who had to eat with their non-dominant hand at less popcorn when they got stale popcorn than when they got fresh popcorn.

There are a few key things to take away from this study.

First, your habits are incredibly powerful. When you are in an environment that supports a habit, you end up carrying out that habit without thinking. If you are interested in habit change, then, you need to become aware of your environment to help stop yourself from behaving mindlessly.

Second, habits are specific to the actions you take. An easy way to help yourself change habits is to find a way to block the actions you normally perform. Just switching hands was enough to get people who eat popcorn regularly to eat less of the stale popcorn.

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