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A new brain imaging study published in Current Biology has uncovered surprising neural activity in people with aphantasia—a condition where individuals report being unable to form mental images. Although they describe a complete absence of visual imagery, their brains still show patterns of activity in the early visual cortex when they attempt to imagine visual stimuli. However, this activity differs in important ways from what’s seen in people who do experience vivid mental imagery, offering insight into how consciousness might be linked to sensory representations in the brain.

Aphantasia is a relatively newly defined condition in which people are unable to form mental images voluntarily. While those with aphantasia can describe objects and scenes using words or concepts, they report no visual “pictures” in the mind’s eye. Since much of what is known about mental imagery comes from people who can generate vivid images, the researchers wanted to know what happens in the brain when someone with aphantasia tries to visualize something. Do they engage the same brain regions, or are there deeper differences in how their brains represent imagined information?

To answer these questions, the research team compared people with aphantasia to individuals with typical visual imagery using functional magnetic resonance imaging (fMRI). The goal was to examine how both groups activated early visual brain regions—especially the primary visual cortex—during attempts to visualize simple stimuli. The researchers focused on whether the brain could still represent specific content in people who lack a subjective visual experience.

The study involved 14 participants with verified aphantasia and 18 control participants with typical imagery. All were right-handed and had normal or corrected vision. Participants completed the Vividness of Visual Imagery Questionnaire to assess their subjective imagery, and their imagery ability was further validated using an objective task called the binocular rivalry paradigm. This method measures how imagining a visual pattern affects what people perceive shortly afterward. As expected, those with aphantasia scored near the floor on the vividness questionnaire and showed little or no sensory bias in the binocular rivalry task, confirming that they lacked typical imagery experience.

In the main experiment, the researchers used fMRI to measure brain activity while participants either viewed or attempted to imagine simple visual patterns—specifically colored Gabor patches—at specific locations on a screen. Each participant completed several types of scans: imagery generation, passive viewing, retinotopic mapping to define visual areas, and region-of-interest localization to pinpoint the parts of the brain involved in processing the stimuli. During the imagery task, participants received a visual cue indicating which pattern to imagine and where to place it in the visual field. After each attempt, they rated how vivid their imagery had felt.

Although people with aphantasia gave extremely low vividness ratings—averaging around 1 on a 1-to-4 scale—their brain activity told a more complex story. In both groups, fMRI signals from early visual areas could be used to decode what kind of pattern a person was trying to imagine. In other words, the brain still encoded specific information about the content of the imagery—even in the absence of subjective experience.

But there were clear differences in how that information was represented. In people with typical imagery, activity in the visual cortex showed expected patterns: stronger responses in the hemisphere opposite to the side of the visual field where the stimulus was imagined. In contrast, people with aphantasia showed the reverse: stronger responses in the same-side hemisphere (ipsilateral) instead of the opposite (contralateral). This suggests a different functional organization of visual activity during imagery attempts.

While the imagery content could be decoded in both groups, only in the control group did the patterns of brain activity overlap between imagery and actual perception. In the control group, algorithms trained on imagery-related brain data could accurately identify visual stimuli seen during passive viewing—and vice versa. This kind of cross-decoding failed in the aphantasia group. Their visual cortex did encode information about imagery attempts, but those patterns did not match those generated during real visual perception.

This mismatch might explain why people with aphantasia experience no visual imagery even though their brains generate structured representations during imagery tasks. According to the researchers, the results point to a difference not just in the strength of visual signals, but in their format. The activity in the visual cortex of people with aphantasia appears to be “less sensory,” meaning it may lack the specific qualities that give rise to conscious visual experience.

The researchers also looked at broader brain networks. During imagery attempts, people with aphantasia showed stronger activity in brain regions associated with language and auditory processing, such as the superior temporal gyri. They also had weaker functional connections between these regions and visual areas. This could indicate that when people with aphantasia try to visualize, they may rely more on verbal or conceptual strategies rather than generating vivid internal images.

To test whether differences in attention or effort might explain the results, the researchers ran a follow-up study with control participants. These individuals were asked to imagine either a clear or blurry version of the same visual patterns. Their reported effort levels and brain activation were similar across both conditions, suggesting that differences in subjective clarity do not necessarily reflect differences in cognitive effort. This makes it less likely that the patterns seen in aphantasia are simply due to lower motivation or task engagement.

Although the findings shed new light on the neural basis of aphantasia, the authors note several limitations. The sample size was relatively small, especially given the rarity of aphantasia, and most participants in both groups were women. Also, while the study focused on low-level visual features, it did not examine whether similar results would hold for more complex images, such as faces or scenes. The absence of eye-tracking during scanning means researchers could not fully rule out whether subtle eye movements influenced the neural signals.

But the results still offer evidence that people with aphantasia can generate structured, content-specific activity in the visual cortex, even though they lack a conscious image. This dissociation between brain activity and experience challenges long-held assumptions that activity in early visual areas is directly tied to visual awareness. Instead, it suggests that not all neural representations are created equal—some may carry enough sensory information to generate conscious images, while others may not.

The study opens new avenues for understanding the neural basis of mental imagery and visual consciousness. Future research could explore what kinds of information are encoded in the brain during imagery attempts in aphantasia, and whether different feedback connections in the brain might account for the altered representations.

The study, “Imageless imagery in aphantasia revealed by early visual cortex decoding,” was authored by Shuai Chang, Xinyu Zhang, Yangjianyi Cao, Joel Pearson, and Ming Meng.