I Can’t Imagine
We’ve discussed senses before. In addition to run-of-the-mill blindness and deafness, you can lack a sense of pain, a sense of balance, a sense of where your body is and what it’s doing. There are all kinds of lacunae in our sensory world, and all kinds of clever ways our brain fills in the gaps.
For those unlucky few with aphantasia, their senses are fully functional. They can see, hear, smell, taste, determine temperature and pressure and pain. Their lack is deeper and more fundamental. They are blind in their mind’s eye.
I want you to try an exercise. Once you’ve finished reading this paragraph, close your eyes. Imagine an apple. It’s red, its surface mottled with slight blemishes and discolorations. One vestigial leaf clings to its fragment of stem. It is shiny. Perhaps there’s a sticker on one side. You’re holding it in your hand. Lift it to your face, rotate it, see it from every angle.
Done? Did you see it? Could you visualize it? For those with aphantasia, the answer to both questions is no. They simply cannot form visual images. They can think; they can imagine; they can remember. But they do so without any pictures in their brain. This condition can be congenital or caused by damage to the brain, but the result is the same. The mind’s eye is blind. They can think, but they cannot imagine.

Blake Ross, who helped create Firefox, has aphantasia. At the age of 30 he became aware that the term “mental image” was not just metaphor or flowery speech; other people had apparently always been able to summon up mental pictures of people or places they had visited. He could not. He knows what people’s faces look like. He can describe them. He can imagine concepts like a red triangle or a beach. But when he does, he doesn’t “see” them in his head. He does not dream often, and when he does, he wakes up with narrative content with no imagery at all; this, he says, is also how he reacts to reading fiction. And for him, this was all normal! For thirty years, he assumed that everyone else was like this as well:
Imagine your phone buzzes with breaking news: WASHINGTON SCIENTISTS DISCOVER TAIL-LESS MAN. Well then what are you?
This is, as you might imagine, difficult to test. It’s a wholly subjective experience. And yet it is testable. There’s a concept called binocular rivalry, where one image is presented to each eye, usually using red-green 3D glasses. You can only see one image, so usually the brain alternates between the two. By priming a subject with descriptions of one of the two images, you can induce them to see one image or the other. Aphantasics can’t be primed in this way; they can’t generate the mental image necessary.
You’d think that aphantasics would have a very hard time just maneuvering around on a day to day basis. So much information is encoded and transmitted visually. But their brains develop workarounds. An aphantastic can tell you what color Tony Blair’s eyes are, or which letters of the alphabet have low-hanging tails. Their brain is coming up with this information somehow, even in the absence of a mental picture.
Aphantasics have a hard time recognizing faces. This isn’t prosopagnosia; when they meet someone they know, they recognize them at once. But once someone dies, the aphantasic can have a hard time visualizing them again, which can be emotionally wracking for the bereaved. They can struggle with fiction, as Blake Ross relates:
And, suddenly, fiction clicks. Paty says I used to worry that “I feel like I’m doing reading wrong.” Descriptive language in novels was important to her but impotent to me; I skip it as reflexively as you skip the iTunes Terms of Service. Instead, I scour fiction like an archaeologist: Find the bones.
The slender, olive-skinned man brushed the golden locks out of his hazel eyes. He was so focused on preparing for the assassination that he burned his tongue on the scalding cuppa joe (hazelnut, light cream).
That becomes: There’s an assassin.
Of course, it’s not all bad news. They can’t count sheep, but aphantasics may be less susceptible to PTSD and other anxiety disorders. The lack of visual imagery may also impede their development of addictions. So few people are aphantasic — one study estimates 2% of the population, but we just don’t have enough data to know for sure. The existence of aphantasia makes me wonder about the internal environments of others. Are they experiencing what I’m experiencing? Or are we going about our lives with radically different mental processes under the hood, each unaware of what we’re missing, each assuming that everyone else is just like us?