My craving for a first coffee of the day hits around 9:15 a.m. I don't drink coffee the first thing in the morning. (What's the point of being alert on a Metro commute?) But by 9:15, my addiction becomes hard to ignore. I can visualize the coffee: the grounds being activated by piping hot water, the feel of a warm mug in my hands, its aroma beckoning me into the world of the wakeful.

I'm not alone in this experience. A craving — whether it be for coffee, alcohol, junk food, drugs, sex, or some other vice — often takes the form of an visual fantasy, researchers in the journal Addictive Behaviors describe in a new study on how to curb these desires.

Playing Tetris for three minutes decreased craving strength for addictive substances by approximately one-fifth.

"Motivation to use a drug or consume food is driven by the imagined experience of achieving that goal," the authors, from universities in England and Australia, explain.

The key then to curb the craving, they hypothesize, is to distract from that visual fantasy.

Enter Tetris, the Russian video game created in 1984. Since its inception, the game has thrilled and infuriated players, enticing them to spend hours stacking irregular polygons into orderly rows.