The Memory Paradox: How Aphantasia Reveals Hidden Pathways in the Brain's Recall System
How a researcher's brain imaging study of people who can't form mental images led to surprising discoveries about memory accuracy, neural noise, and the multiple pathways our minds use to access the past.
8 min readByAphantasia Network
The Memory Paradox: How Aphantasia Reveals Hidden Pathways in the Brain's Recall System
When Merlin Monzel asked his audience to remember their last holiday—to visualize the blue sea, hear the crashing waves, feel the warm sand—he knew that roughly 4% of listeners would experience nothing but darkness. Yet his groundbreaking research at the University of Bonn reveals these individuals aren't missing memories at all. They're accessing them through an entirely different neural highway.
Monzel's latest study, using high-resolution brain imaging of people with aphantasia during memory recall, has uncovered a counterintuitive finding that challenges decades of assumptions about how human memory actually works. The results suggest that people who cannot form mental images may have more accurate factual recall than those who can—and their brains are working harder, not less, during the memory process.
The Holiday That Never Came to Life
"Remember last time you were on holiday," Monzel began his recent presentation. "How was it like? Do you remember the sea and can you hear the sound of the waves? What color was the beach and how did the sand feel between your toes?"
For most people, this exercise triggers what researchers call episodic memory—rich sensory simulations that make past experiences feel vivid and immediate. But Monzel's research focuses on those for whom this instruction falls flat: people with aphantasia who experience memory as pure knowledge without sensory re-experiencing.
"Many of you might experience problems with this step because you cannot create mental imagery to re-experience these sensory sensations," Monzel explained to his audience, setting up the central question his research addresses: if mental imagery is supposedly crucial for autobiographical memory, how do people with aphantasia remember their lives at all?
Two Roads to the Same Memory
Monzel's team has developed a model that explains memory retrieval as following two distinct neural pathways. The first creates what he calls a "semantic scaffold"—basic factual information like when, where, and with whom an event occurred.
"However, at this stage these are only semantics," Monzel noted. "There is no quality of reliving. You only know this has happened to you but you don't re-experience it."
The second pathway fills this factual framework with episodic details through sensory simulations.
"After the semantic scaffold is created, people start to fill the scaffold with episodic details which are often sensory in nature—for example, how warm was the sun, which color had the bucket, or how did the hot dog taste like."
His hypothesis: people with aphantasia excel at the first pathway while struggling with the second, leading to fundamentally different—but not necessarily inferior—memory experiences.
The Brain Scans That Flipped Everything
Using fMRI technology to peer inside the brains of 14 people with aphantasia and 16 typical visualizers during memory recall tasks, Monzel's team made discoveries that defied expectations.
First, people with aphantasia showed significantly less activation in the hippocampus—the brain region long considered the master coordinator of autobiographical memory. "We found less activation in the hippocampus where the episodic memory index is located," Monzel reported.
But the real surprise came from the visual cortex. Instead of showing reduced activity, as researchers expected, people with aphantasia displayed heightened activation during memory tasks.
"More activation in the visual cortex where we think the visual retrieval process is located," Monzel observed, describing results that initially seemed to contradict everything the field thought it knew about aphantasia.
The Nightclub Theory of Mental Noise
To explain this paradoxical finding, Monzel developed what might be called the "nightclub theory" of aphantasia. Mental imagery, he suggests, requires a clear signal from memory networks to the visual cortex. But in people with aphantasia, too much background activity creates interference.
"We can compare this to a wizard in a club," Monzel explained. "The imagery signal is a voice... however, the surrounding music in the club is very, very loud... so that we cannot extract our imagery signal from the noise that is surrounding it."
The heightened visual cortex activity in aphantasia isn't helping create mental images—it's preventing them. "Too much activation in the visual cortex might interfere with imagery signals so that no mental image can be created by aphantasics."
This aligns with a broader principle in neuroscience called neural efficiency: skilled processes often require less brain activation, not more. When systems work smoothly, they operate quietly. When they struggle, they generate noise.
The Broken Telephone Line
Perhaps the most significant finding involved connectivity between brain regions. In typical visualizers, the hippocampus and visual cortex showed strong communication during memory tasks—like two parts of a well-coordinated team.
"In control participants there was a good connection between hippocampus and visual cortex, so both structures were communicating," Monzel reported.
In people with aphantasia, this communication virtually disappeared. "But in aphantasics, the communication was nearly zero."
This suggests aphantasia isn't simply about having a "broken" visual system. Instead, it appears to involve disrupted coordination between memory and visualization networks—like having a telephone line that can't connect two otherwise functional systems.
Memory Without Movies
The practical implications of these neural differences became clear in Monzel's behavioral studies. When recounting autobiographical memories, people with aphantasia consistently reported fewer sensory details than typical visualizers.
"Aphantasics reported less episodic details than controls," Monzel found. "However, for semantic memory details, for the semantic scaffold, there was no difference."
This pattern held across both recent and distant memories, suggesting people with aphantasia don't lose memories over time—they simply access them differently from the start.
The difference played out in real-world scenarios shared by study participants. One audience member described going to a restaurant: "My friend who visualizes recalled the waitress's face. I remember she had a chin piercing and tattoo. She didn't."
Monzel identified this as a classic example of the two memory systems at work. "The semantic information is just knowing it was someone with a piercing, and the visual information, the episodic information, is visualizing the face, seeing the piercing."
The person with aphantasia had used what Monzel calls "labelling"—identifying and storing one particularly salient feature rather than trying to encode the entire visual scene.
The Accuracy Advantage
These findings hint at a potential advantage for people with aphantasia: their memories might be more factually accurate. Without the ability to reconstruct vivid sensory details, they may be less prone to the false memories that can plague typical visualizers.
"Non-aphantasics have memory problems too," Monzel pointed out. "They have wrong memories, inflated memories, they have memory loss all the time and they don't even know because they think 'yeah, I know everything' because they can conjure something up which wasn't actually there."
In contrast, "aphantasics, when they remember, they are really sure that it actually happened because it is a semantic fact and not only some picture I imagined before."
This suggests people with aphantasia might serve as more reliable witnesses or historians—their inability to generate false sensory details could protect them from certain types of memory distortions.
Beyond Vision: The Multisensory Question
While Monzel's current study focused exclusively on visual memory, it raises broader questions about how aphantasia affects other senses. If the hippocampus serves as a general "episodic memory index," problems with this system might extend beyond vision.
"When the episodic memory index is affected as a whole, we should find the same results as in our study when remembering sounds, tastes, smells, touches, or even feelings," Monzel hypothesized.
His team is now developing objective measures for these other sensory modalities, moving beyond the self-report questionnaires that have dominated aphantasia research.
Implications for Attention and Emotion
The heightened visual cortex activity Monzel observed might affect more than just memory. His team suspects it could influence how people with aphantasia direct their attention and process emotions.
"We expect that aphantasics are more likely to direct their attention to external stimuli because there's so much external activation in the visual cortex, and they are less able to direct their attention to internal stimuli such as mental imagery or, for example, even feelings."
This could explain previous findings that people with aphantasia show reduced emotional reactivity—their brains might be biased toward processing external information rather than internal experiences.
A Road Map for Future Intervention
The connectivity findings offer hope for potential treatments. If aphantasia results from poor communication between brain regions rather than damage to specific areas, the problem might be addressable.
"If it is a functional connectivity problem, then theoretically it is possible to influence brain connectivity," researchers in related fields have suggested, using techniques like transcranial magnetic stimulation or neurofeedback training.
The goal would be to strengthen the communication channels between the hippocampus and visual cortex, potentially allowing some people with aphantasia to develop mental imagery abilities.
Living with Different Memory
For people discovering they have aphantasia, Monzel's research offers both scientific validation and practical guidance. The condition isn't a disability—it's a different way of accessing the same underlying information.
"I would explain to my family and my friends my way of thinking so there's no disappointment when I forget something or I cannot remember something," Monzel advised, emphasizing the importance of managing social expectations around memory performance.
He also suggested compensation strategies:
"Maybe there can be verbal strategies like labeling to find a feature and remember the feature, the label of the feature. There can be externalizing strategies like using photos or diary to help my memory."
Redefining Normal Memory
Monzel's research fundamentally challenges the assumption that vivid sensory memory represents the gold standard of human recall. Instead, it reveals memory as a more diverse and flexible system than previously imagined.
People with aphantasia aren't broken—they're using alternative neural pathways to access the same information, sometimes with greater accuracy than those who rely on potentially unreliable sensory reconstructions.
As neuroscience continues mapping the varied landscapes of human consciousness, studies like Monzel's reveal that our inner experiences are far more diverse than we assumed. The mind's eye may be just one window into memory—and for millions of people, other windows work just as well, or perhaps even better.
The implications extend beyond aphantasia research. If the same memories can be accessed through multiple neural pathways, it suggests human cognition is more resilient and adaptable than we thought. Understanding these alternative routes doesn't just help us comprehend aphantasia—it illuminates the hidden flexibility of the human mind itself.
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Aphantasia Network is shaping a new, global conversation on the power of image-free thinking. We’re creating a place to discover and learn about aphantasia. Our mission is to help build a bridge between new scientific discoveries and our unique human experience — to uncover new insight into how we learn, create, dream, remember and more with blind imagination.
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