Anyone with an unusual name has experienced the frustration of trying to get it across to a new acquaintance: The hearer betrays bewilderment, seems to be mentally shuffling through a card file of all previously known names, and settles on some remote approximation or gives up entirely. It’s as if names can only be remembered if someone is already familiar with similar appellations.

The notion that the ability to remember new information often depends on prior knowledge of the topic is well known. Now, researchers in Edinburgh, Tokyo, and Trondheim, Norway, have conducted a study that helps answer one of the most important questions in neuroscience: Why is it that the more people know, the more they can learn?