When done right, games exert a strong psychological influence over consumers, says Amy Jo Kim, a game designer who worked on hits such as Rock Band after earning a PhD in behavioral neuroscience. "What games do is help you come up with stories about yourself," she says. Earning points or reaching new levels creates the illusion of progress and is akin to "telling you a story about yourself getting better and stronger and more powerful," she says.
Social status is another motivator. "We have this tendency to care about what image we portray," says Dan Ariely, a professor of behavioral economics at Duke University. In real life, there are mansions and handbags. "In the gaming world," says Ariely, "there are badges."