People recalling a familiar image use different brain mechanisms to focus on a component than those who are viewing the situation live, a new study indicates. The reasons why the brain has evolved a different process for this task are not known, but might hold the key to understanding why some people have this capacity and others do not.

A few years ago, many frequent Internet users were astonished to discover that some people have no “mind’s eye”, the capacity to visualize things that they cannot see at the time, also known as aphantasia. A smaller group were at least as amazed to learn that other people can, and that references to such capacities were not merely metaphorical. 

Possibly influenced by these exchanges, research into the working of the mind’s eye, where it exists, has picked up, for example finding that psychedelics may switch it on. The most recent example investigated how the brain responds when challenged to focus on part of a remembered map, in contrast to a scene laid out before it, revealing crucial differences.