This is an audio long read from nature. In this episode, many people have no mental imagery.

What's going on in their brains? Written by Elizabeth Quill and read by me, Benjamin Thompson.

Think about your breakfast this morning.

Can you imagine the pattern on your coffee mug, the sheen of the jam on your half-eaten toast?

Most of us can call up such pictures in our minds.

We can visualize the past and summon images of the future.

But for an estimated 4% of people, this mental imagery is weak or absent. When researchers ask them to imagine something familiar, they might have a concept of what it is,

and words and associations might come to mind, but they describe their mind's eye as dark or even blank.

Systems neuroscientist Max Shine at the University of Sydney, Australia, first realized

that his mental experience differed in this way in 2013. He and his colleagues were trying to

understand how certain types of hallucination come about

and were discussing the vividness of mental imagery.

When I close my eyes, there's absolutely nothing there, Shine recalls, telling his colleagues.

They immediately asked him what he was talking about.

Whoa, what's going on? Shine thought. Neither he nor his

colleagues had realized how much variation there is in the experiences people have when they close

their eyes. This moment of revelation is common to many people who don't form mental images.

They report that they might never have thought about this aspect of

their inner life, if not for a chance conversation, a high school psychology class, or an article

they stumbled across. Although scientists have known for more than a century that mental imagery

varies between people, the topic received a surge of attention, when,

a decade ago, an influential paper coined the term Afantasia to describe the experience of people

...