The condition you are describing, where you can recognize faces but cannot form mental images or pictures of them in your mind, is known as "aphantasia."
Aphantasia is a phenomenon where individuals lack the ability to create voluntary mental images or visual imagery. People with aphantasia typically have no trouble recognizing objects, including faces, when they are presented to them in the real world. However, they are unable to conjure up mental pictures or visualize images in their mind's eye.
This condition varies in severity among individuals. Some people may have a complete lack of mental imagery across all senses, while others may experience aphantasia only for specific senses, such as visual imagery, but still be able to imagine sounds, smells, or other sensory experiences.
Aphantasia is a relatively rare condition, and researchers are still exploring its underlying causes and the mechanisms behind it. Some individuals may have had aphantasia throughout their lives, while others may experience it as a result of certain neurological conditions or brain injuries.
If you believe you may have aphantasia or are concerned about your ability to visualize, it's essential to consult with a qualified healthcare professional or neurologist for an evaluation and further information. They can provide a proper diagnosis and offer guidance or coping strategies if needed.