Visual Mental Imagery in Typical Imagers and in Aphantasia: A Millimeter-Scale 7-T fMRI Study

Jianghao Liu, Minye Zhan, Dounia Hajhajate, Alfredo Spagna, Stanislas Dehaene, Laurent Cohen, and Paolo Bartolomeo. Cortex. 2025.

One of the biggest open questions in aphantasia research is what is actually different in the brain. Not just behaviorally, but neurologically. This team at the Paris Brain Institute used one of the most powerful brain scanning tools available, a 7-Tesla fMRI machine that produces images at millimeter-scale resolution, to look at what happens in the brains of people with and without aphantasia when they try to imagine something.

This piece of research I found through this reddit post which includes a youtube video with an interview with one of the researchers.

The Question

When a person with aphantasia tries to imagine something, does their visual brain simply not activate? Or does something else go wrong? And where exactly does the process break down?

The Discovery

When both groups tried to imagine things like shapes, colors, faces, and spatial locations, the visual areas of the brain activated in remarkably similar ways. People with aphantasia were not simply running dark screens. Their brains were doing something. Both groups also performed equally accurately on the imagery tasks, though aphantasics were on average .21 seconds slower, suggesting they were working harder to get there. Harder, but not by much.

The difference showed up in communication, not activation. There is a specific region in the left side of the brain called the Fusiform Imagery Node, or FIN, that appears to act as a hub for visual imagery across different types of content. Both groups activated this hub equally. But in typical imagers, the FIN was strongly connected to the prefrontal and parietal networks, the parts of the brain involved in conscious awareness and goal-directed thought. Nine out of 10 typical imagers showed that connection. Only 5 out of 10 aphantasics did. In aphantasic participants no brain region showed increased functional connectivity with the FIN during imagery at all. The visual information was there but the connection that would make it a conscious experience was not completing the loop.

The Catch

This study had only 10 participants per group, which is a small sample for drawing firm conclusions even with highly precise imaging. Participants were also recruited from French-language aphantasia groups on social media, so the sample is self-selected rather than randomly drawn. People who find and engage with aphantasia communities online tend to be the ones who have already developed language for their experience and built workarounds for navigating a visualizer's world. They may have become so bilingual in translating visualizer language that their aphantasia no longer shows up clearly in surveys or conversations. 

The Insight

Aphantasia does not appear to be a failure to generate visual information in the brain. It appears to be a failure to integrate that information into conscious experience. The brain produces the signal. The network that would broadcast it as something you can actually see in your mind is not fully connecting.

The One Thing to Remember

A person with aphantasia is not missing visual processing. Their brain is doing more work than you might expect, just not completing the final step that produces a subjective image. For teachers and therapists this matters because it means the information is getting in. The barrier is not comprehension or effort. It is the step that turns processed information into an experienced picture. Knowing that should change how you think about what these students and clients actually need.

The Connection

The No Picture Needed paper describes aphantasia as a difference in how information is accessed rather than a deficit in intelligence or knowledge. This study gives that description a neural address. The information is arriving. The visual brain is responding. What is not happening is the connection between the visual hub and the networks that would make the image conscious. The guide describes a filing cabinet full of accurate data. This paper shows that the filing cabinet has the files. The problem is in the delivery system between the cabinet and the part of the brain that would put the image on the screen.

You can read the full paper by clicking here.