For most people, recalling a childhood memory, a loved one's face or a favourite placer e instantly brings up a mental picture. It feels so natural that few ever stop to wonder whether everyone experiences thoughts in the same way.
But researchers say that is not the case. According to neurologist Professor Adam Zeman, millions of people live with a little-known cognitive difference called aphantasia, often without realising it, reports LADbible.
A hidden difference
Aphantasia is the inability to voluntarily create mental images. While most people can picture an object, person or location in their mind, those with the condition rely on concepts, facts and knowledge instead of visual imagery.
The condition does not affect intelligence, creativity or memory. People with aphantasia still know what an object looks like and can describe it in detail, even if they cannot see it internally.
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Some individuals experience a broader form known as global aphantasia, where imagined sounds, tastes and other sensory experiences may also be absent.
Often discovered late
One reason aphantasia remained largely unknown for so long is that many people assume everyone thinks the same way they do.
As a result, some only discover the condition later in life after learning that other people can consciously generate vivid mental images.
Researchers have also identified cases where aphantasia developed following injury, although many people appear to have had it since birth.
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More common than expected
Studies suggest that visual aphantasia may affect around 4-5% of the population, while broader definitions could place the figure even higher.
According to research cited by Professor Zeman, as many as 10% of people worldwide may fall somewhere on the aphantasia spectrum.
That means millions could be experiencing the world differently without ever knowing there is a name for it.
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This article is made and published by Mie Hermansen, who may have used AI in the preparation.