To people with aphantasia, the mind is a place for mulling over words and concepts. Dreaming up images, on the other hand, is not something those with this newly named condition are able to do. In a letter to the editor published earlier this summer in the journal Cortex, University of Exeter neurologist Adam Zeman and two colleagues write about their work with people who say they are incapable of visual imagery, and the cognitive phenomenon they describe is fascinating.
Few studies have been published investigating this strange condition, though one 2009 survey of 2,500 adults found that about 2.5 percent of participants reported having “no visual imagination.” Zeman and his colleagues wrote their letter in part to encourage more research into the condition, as there haven’t yet been been any large-scale investigations. It’s also unclear why people with aphantasia are unable to form mental pictures, although the authors write that existing research does point to certain regions of the brain — such as the retinotopic areas in the occipital lobe — that are thought to be linked to the mind’s eye.
From their interviews with 20 individuals who say they are unable to think in images, Zeman and his co-authors have so far found that not every person’s experience with aphantasia is exactly alike, to say the least. Some say they dream in pictures, which could mean that aphantasiacs can’t think up voluntary images, but the involuntary ones that happen in dreams occur just like they would with anyone else. But others say they don’t see images when they dream (or, perhaps, it’s that they don’t remember them if they do). Many of their subjects blanked when asked to recall visual memories, but others do okay on these questions — though this could be because they’ve found ways to work around their impairment, such as committing facts and figures about the visual world to memory.
Sounds strange, but, for what it’s worth, some aphantasiacs probably think those of us who can conjure up mental pictures are the strange ones. As the new science-of-sleep site Van Winkle’s reports, when one person with aphantasia learned about the idea of the “mind’s eye” from his wife, he assumed this must just be some “spooky gift” of hers. If you’ve only ever thought in words, the idea that the inside of some people’s minds look more like picture books must be an odd idea, indeed.