One trick, known as the journey method or 'memory palace,' is to conjure up a familiar space in the mind's eye, and then populate it with images of whatever it is you want to remember.

All across Africa, the Pacific and the Americas, we find cultures that didn't know about mouth kissing until their first contact with European explorers. And the attraction was not always immediately apparent. Most considered the act of exchanging saliva revolting.

The more we remember, the better we are at processing the world. And the better we are at processing the world, the more we can remember about it.

What distinguishes a great mnemonist, I learned, is the ability to create lavish images on the fly, to paint in the mind a scene so unlike any other it cannot be forgotten. And to do it quickly. Many competitive mnemonists argue that their skills are less a feat of memory than of creativity.

Jonah Lehrer is one of the most talented explainers of science that we’ve got. What a pleasure it is to follow his investigation of creativity and its sources. Imagine is his best book yet.

Over the last few millennia we've invented a series of technologies - from the alphabet to the scroll to the codex, the printing press, photography, the computer, the smartphone - that have made it progressively easier and easier for us to externalize our memories, for us to essentially outsource this fundamental human capacity.

What makes things memorable is that they are meaningful, significant, colorful.