While aphantasia has been acknowledged in medicine since the 1800s, the mechanisms behind it have never been fully explained.

When someone with aphantasia does try to imagine something, they simply can’t and instead see a void of darkness. Neuroscientist and author of The Source Tara Swart, M.D., Ph.D., explains that aphantasia is complex, and its effect on people can vary.

For example, she says it can also manifest as the inability to recognize faces, form visual memories, or imagine something new that you haven’t seen before.

Swart adds that the condition has “no bearing on intelligence or any other neurological syndrome.”

One explanation for why aphantasia might occur has to do with childbirth and brain development, Swart says. “During the process of childbirth, when the brain is very undifferentiated […] babies actually have a series of mini-strokes.”

Thanks to neuroplasticity, she explains, a baby’s brain is usually able to adapt and build more neurons following those strokes. But in the case of aphantasia, “That tiny little pathway that’s related to visual imagery or visualization just doesn’t work.”

Presently, there is no treatment for the condition. But with the proper understanding and tools, people with aphantasia can still thrive.