People revealed “afantasy” – the lack of visual imagination

(ORDO NEWS) — Visual imagination – or rather, lack of it – can be tested by measuring pupillary dilation, the first physiological evidence of aphantasy, a new study has found.

A study led by scientists from UNSW Sydney and published in eLife found that the pupils of people with aphantasy do not respond to a request to imagine dark and light objects, while people without aphantasy do.

To assess the pupillary reflex in non-aphantasy people, the researchers recruited 42 study participants who, according to their own data, have visual imagination, and provided them with glasses to track eye movements and pupil size.

Participants were then shown bright or dark figures against a gray background, which predictably caused pupils to constrict in response to bright figures (comparable to looking at a bright sky) and pupils to dilate in response to dark figures (after turning off the lights).

Then, to test visual imagery – the ability of the mind to visualize objects – participants were asked to simply imagine the same light or dark figures (with their eyes open so they could follow the pupils) and then report the “brightness” of those images.

The researchers found that even in response to imagined bright and dark figures, the participants’ pupils still constricted and dilated appropriately, with the pupillary reflex being stronger in those who reported greater vividness of the imagination.

“The pupillary reflex is an adaptation that optimizes the amount of light reaching the retina,” says Professor Joel Pearson, senior author on the paper.

“While it was already known that imaginary objects can cause so-called ‘endogenous’ changes in pupil size, we were surprised to see more significant changes in those who reported brighter images. This is indeed the first biological, objective test for imaginative brightness.” .

Test for lack of imagination

Finally, having established a link between visual images and pupillary response, the researchers tried to test this effect in people with aphantasy. The researchers repeated the study with 18 participants who self-reported having aphantasy.

By presenting participants with bright and dark figures, the researchers found that people with aphantasy had the same pupillary response as people in general: constriction to bright figures and dilation to dark ones.

However, in the second component of the study, where participants were asked to visualize the same figures, the pupillary responses of non-phantasy people were not significantly different in response to imagined dark and imagined bright objects.

“One of the problems with many of the existing methods for measuring imagery is that they are subjective, that is, they depend on the ability of people to accurately assess their own imagery.

Our results show a new exciting objective method for measuring visual images,” says Professor Pearson, “and the first physiological evidence of aphantasy “.

With over 1.3 million Australians considered to have aphantasy, and another 400 million worldwide, we are now close to an objective physiological test, such as a blood test, to determine if a person truly has aphantasy.”

Although the pupils of people with aphantasia did not differ in the presentation of light and dark objects, they showed a difference in the presentation of one and four objects, indicating greater mental effort, thus refuting the explanation for the non-participation of people with aphantasia.

“Our pupils are known to enlarge when we perform a more difficult task,” says Lachlan Kay, PhD at the Future Minds Lab, UNSW. Visualizing four objects at the same time is more difficult than one.”

The pupils of participants with aphantasy dilated when they imagined four figures compared to one, but did not change depending on whether the figures were bright or dark. This indicates that participants with they really tried to imagine with aphantasy in this experiment, just not in a visual way.

“The pupil response of aphantasics to the four-object condition is also a very interesting finding,” adds Prof. don’t try to create a mental image.”

These results are also very interesting in relation to memory and aphantasy, says Dr. Rebecca Keogh, postdoctoral researcher at Macquarie University and co-author of the study.

Our previous work has shown that people with aphantasy are able to perform visual working memory tasks, remembering many images in a short period of time without using visual images.”

“These results further highlight the wide variability of the human mind, which can often remain hidden until we ask someone about their inner experience or invent new ways to measure the mind. This reminds us that if I remember or I represent something in one way, it does not mean that everyone does it.”

What’s next for aphantasy research? A look into the future…

Next, Prof. Pearson and his team at the Future Minds Lab plan to explore how this new method can be scaled up and launched online to provide a global, efficient, and objective measurement of imagery and afantasy.

“This is a truly exciting time. We are very close to having objective, reliable tests of extreme imagery, afantasy and hyperfantasy (extremely strong visualizations) that can be scaled and run online for millions of people around the world,” says the professor. Pearson.

“We know that thoughts with or without pictures affect the amount of detail in lifelong memories, the emotionality of reading, and how we retain information in short-term memory.

This new method will allow us to understand the brain mechanisms of extreme imagery and the global consequences how we think, decide and feel.”


Contact us: [email protected]

Our Standards, Terms of Use: Standard Terms And Conditions.