9 Brain Disorders That Completely Warp Your Reality

6. Aphantasia: Imagination Blind

You might not have the best imagination in the world, but most of us take it for granted that we are able to picture a loved one's face, or visualise a route in our mind's eye. However, for people with a condition known as aphantasia, it is as though their mind's eye is blind, and they are unable to mentally "picture" anything.

What those with aphantasia "see" instead is understandably difficult to describe. One sufferer describes it like remembering information:

When I think about my fiancee there is no image, but I am definitely thinking about her, I know today she has her hair up at the back, she's brunette [...] But I'm not describing an image I am looking at, I'm remembering features about her

In an odd twist, those with aphantasia often report that they are able to dream visually, and it is only their waking mind that is unable to conjure images.

The condition is remarkably common and, given how subjective something like the "mind's eye" is, some even estimate that as many as one in 50 people could have it. As such, some experts don't actually regard it as a disorder at all, but rather as a normal variation in how the human mind works from person to person.