Unsupervised clustering reveals spatial and verbal cognitive profiles in aphantasia and typical imagery

DOI: 10.1016/j.neuropsychologia.2025.109279

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Delem, M., Turkben, S., Cavalli, E., Cousineau, D., & Plancher, G. (2025). Unsupervised clustering reveals spatial and verbal cognitive profiles in aphantasia and typical imagery. Neuropsychologia, 219, 109279. doi:10.1016/j.neuropsychologia.2025.109279

Abstract

Mental imagery is a ubiquitous phenomenon for many people. Its absence - aphantasia - has recently attracted increasing scientific interest. Individuals with aphantasia are found to perform as well as typical imagers in most areas. Several studies have proposed that individuals with aphantasia might have a more ‘semantic and abstract’ mode of functioning. The present study aimed to better understand the cognitive profile of individuals with aphantasia by examining their performance regarding semantic and abstract processing. To that end, 45 participants with aphantasia and 51 controls completed questionnaires and behavioural tasks assessing sensory and spatial imagery, verbal strategies, verbal and non-verbal reasoning, and verbal and spatial working memory. Initial group comparisons revealed minimal differences. Rather than limiting our investigation to predefined group comparisons, we then adopted a trans-categorical, data-driven approach to uncover latent cognitive profiles based on task performance and subjective reports. Unsupervised clustering across the full sample revealed three clusters of cognitive profiles centred respectively on visual imagery, spatial imagery and verbal strategies. Crucially, individuals with aphantasia were distributed across two of these profiles. One showed low visual imagery but maintained multisensory imagery and high spatial imagery, while the other displayed low imagery across all sensory modalities and stronger reliance on verbal processing. These findings reveal significant heterogeneity within both aphantasia and control groups, extending beyond differences in visual imagery. They highlight the importance of considering spatial and verbal cognitive dimensions alongside visual phenomenology. By identifying cognitive profiles that transcend traditional imagery classifications, our results support a multidimensional framework for understanding how individual differences in mental representation relate to behaviour.

Authors

Maël Delem4
Sema Turkben1
Eddy Cavalli3
Denis Cousineau1
Gaën Plancher6

What This Study Is About

Researchers wanted to understand if people with aphantasia—the inability to create mental images—use different "thinking styles" to solve problems. They looked at whether aphantasics rely more on spatial thinking (understanding where things are) or verbal thinking (using words and logic) to compensate for their lack of visual imagery.

How They Studied It

The study included 45 people with aphantasia and 51 "typical" imagers. Participants completed a wide range of tasks, including:

Questionnaires about their use of visual, spatial, and verbal strategies.

Reasoning tests involving patterns and logic.

Memory tests for words and locations.

Reading comprehension and executive function (problem-solving) tasks.

Instead of just comparing the two groups, the researchers used a computer method called "clustering" to see if participants naturally fell into different profiles based on how they processed information.

What They Found

The study found that people with aphantasia are not all the same. They generally fell into two distinct "profiles":

1. The Spatial Group: These individuals had low visual imagery but high spatial imagery (the ability to mentally manipulate objects and locations) and multisensory imagery (like imagining sounds or smells).

2. The Verbal Group: These individuals had low imagery across all senses and relied much more heavily on verbal strategies and words to think.

Crucially, the researchers found that aphantasics performed just as well as typical imagers on almost all cognitive tasks, including memory and reasoning, by using these alternative spatial or verbal "routes."

What This Might Mean

This suggests that aphantasia is not a "deficit" in thinking, but rather a different way of organizing the mind. It shows that the brain is flexible; if it cannot use a "mental picture," it can successfully use spatial maps or verbal logic to achieve the same results. However, because the study used a relatively small group, more research is needed to see if these profiles exist in the wider population.

One Interesting Detail

Despite having no "mind's eye," many people in the aphantasia group reported having very strong "spatial imagery," proving that "seeing" an object in your mind is a completely different brain process than "knowing" where that object is in space.

Unsupervised clustering reveals spatial and verbal cognitive profiles in aphantasia and typical imagery

Abstract

Authors

Unsupervised clustering reveals spatial and verbal cognitive profiles in aphantasia and typical imagery

Abstract

Authors

Unsupervised clustering reveals spatial and verbal cognitive profiles in aphantasia and typical imagery

Abstract

Authors

Unsupervised clustering reveals spatial and verbal cognitive profiles in aphantasia and typical imagery

Abstract

Authors

What This Study Is About

How They Studied It

What They Found

What This Might Mean

One Interesting Detail

What This Study Is About

How They Studied It

What They Found

What This Might Mean

One Interesting Detail

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