The Stanford marshmallow (棉花糖) test was originally conducted by psychologist Walter Mischel in the late 1960s. Children aged four to six at a nursery school were placed in a room. A single sugary treat, selected by the child, was placed on a table. Each child was told if they waited for 15 minutes before eating the treat, they would be given a second treat. Then they were left alone in the room. Follow-up studies with the children later in life showed a connect ion between an ability to wait long enough to obtain a second treat and various forms of success. 

As adults we face a version of the marshmallow test every day. We' re not tempted (诱惑) by sugary treats, but by our computers, phones, and tablets — all the devices that connect us to the global delivery system for various types of information that do to us what marshmallows do to preschoolers.

We are tempted by sugary treats because our ancestors lived in a calorie-poor world, and our brains developed a response mechanism to these treats that reflected their value — a feeling of reward and satisfaction. But as we've reshaped the world around us, dramatically reducing the cost and effort involved in obtaining calories, we still have the same brains we had thousands of years ago, and this mismatch is at the heart of why so many of us struggle to resist tempting foods that we know we shouldn't eat.

A similar process is at work in our response to information. Our formative environment as a species was information-poor, so our brains developed a mechanism that prized new information. But global connectivity has greatly changed our information environment. We are now ceaselessly bombarded (轰炸) with new information. Therefore, just as we need to be more thoughtful about our caloric consumption, we also need to be more thoughtful about our information consumption, resisting the temptation of the mental "junk food" in order to manage our time most effectively.