December 14, 2025

Sophia Nguyen

Fountain Valley High School

11th Grade

Can you imagine an apple? What color is it? Can you make it spin? Is it clear, or just a blurry picture? Could you do all that? While most people can, it is estimated that about 1-5% of the population cannot. This condition is called aphantasia, which comes from the Greek words “a” (without) and “phantasia” (meaning imagination). It is not a disorder, as it does not affect people’s lives significantly; rather, it is seen as a quirk in humans, like being left-handed.

Imagination exists on a spectrum, with some people being unable to imagine (aphantasia) and others having exceptionally vivid imagination (hyperphantasia). There are two main types: congenital aphantasia and acquired aphantasia. Congenital aphantasia, which means being born with it, is the most common form. Acquired aphantasia usually occurs after damage to the brain, such as a stroke or concussion.

Aphantasia is not well researched and not well understood. Current studies suggest that aphantasia is not a complete lack of imagination but rather the lack of voluntary imagery. Multiple parts of the brain work together in tandem to create an image. The prefrontal cortex initiates the intent to visualize, which then signals to the temporal lobes to retrieve conceptual and visual memory. This signal then travels to the visual cortex (occipital lobe), which processes actual sight. This area activates to “display” the mental image. 

To find physiological differences between aphantasiacs and people with typical imagery, researchers studied both groups using fMRIs. Aphantasiacs show a significant reduction in activation within the visual cortex when asked to visualize an image. While their prefrontal cortex (intent to imagine) activates, the signals sent to the other parts of the brain, such as the visual cortex, do not seem to connect properly. This suggests that aphantasia is linked to differences in functional connectivity. 

Aphantasia is usually self-diagnosed through the Vividness of Visual Imagery Questionnaire (VVIQ). Since these self-reports are subjective, researchers sought to create objective criteria for measurement. One notable study found differences through binocular rivalry. Two groups, one control and one of aphantasiacs, were shown two different images simultaneously, one to each eye. The brain cannot fuse the two images together when separated, which causes the brain to switch back and forth between the two images. Both groups were primed by asking them to imagine one of the images first. The control group showed that if they were primed, they were significantly more likely to see that image first. The aphantasic group showed no priming effect, which provides definitive evidence of a psychological difference between aphantasiacs and people with typical imagery.

Another method involved measuring the pupillary light reflex. When a typical person is asked to visualize a bright scene, for example, the sun, their eyes would constrict slightly, as they would in bright light. Studies have shown that this involuntary physiological response is often absent or significantly reduced in people with aphantasia. 

Aphantasia affects how a person interacts with and remembers the world. For example, many people with aphantasia also experience Severely Deficient Autobiographical Memory (SDAM). This highlights two different types of memory: episodic memory (reliving the scene) and semantic memory (fact-based knowledge). A person with episodic memory may be able to remember a day out with friends, “reliving” the scene through “hearing” their friends laughing, “feeling” the wind in their hair, etc., while a person with aphantasia would know what they did and with whom, but they would not “relive” the moment. Rather than a mental movie, memories are stored as facts and concepts.

A fascinating discovery is that most people with congenital aphantasia still have visual dreams. This supports the idea that aphantasia is caused by neural pathway dysfunction rather than deficiencies in the visual cortex itself. This also explains the distinction between voluntary and involuntary imagery. Many aphantasiacs experience involuntary images, perhaps due to this distinction. This also suggests treatments for aphantasia may be possible through neural network interventions.

In summary, aphantasia is a complex neurological phenomenon that affects voluntary mental imagery, but it does not impair cognitive function significantly. So, when you imagine that apple (or if you cannot), think about how unique and special that is.