Aphantasia is the inability to voluntarily form mental images. 

People with aphantasia cannot visualize faces, places, or objects in their mind's eye. It's not a disorder, but rather a difference in how the brain processes information, with some individuals developing alternative strategies for memory and problem-solving.

 

Approximately 1-4% of the population is estimated to experience aphantasia.

 

Average IQ is, if anything, marginally higher in people with aphantasia than hyperphantasia