“One plausible explanation is that the pupil light response reflects, among other things, activity in visual brain areas.

Sebastiaan Mathot, assistant professor in experimental psychology at the University of Groningen in the Netherlands, who was not involved in the study, told MNT: When asked what may explain the findings, Dr. The researchers further discovered that people with aphantasia exerted more cognitive effort when trying to imagine four shapes as opposed to one. Meanwhile, they found that the luminance and vividness of images-either perceived or imagined-had no significant effect on the pupillary size of those with aphantasia, reflecting their lack of subjective visual imagery. In the end, the researchers found that in people without aphantasia, the vividness and luminosity of images- whether perceived or imagined-significantly influenced their pupillary light response. The participants also engaged in other experiments and filled in a questionnaire to ensure a lack of decisional bias and inattention in their answers, as well as whether or not they had aphantasia. The researchers measured the size of their pupils throughout. They also recruited 18 individuals with aphantasia at an average of 35.8 years old.įor the study, all of the participants perceived and were later asked to imagine 32 white or gray shapes. The researchers recruited 42 psychology students with a mean age of 19.8 years who did not have aphantasia. people with aphantasia -who imagine in a more abstract way because they cannot build a picture in their mind’s eye-don’t show the same effect,” she told Medical News Today. “This suggests that their imagination is treated a simulation of the real world. Julia Simner, who leads the MULTISENSE lab at the University of Sussex, and was not involved in the study. “The fascinating finding reported here is that people imagining light or dark objects show the same type of pupillary action as we would normally find when the eyes are exposed to light and dark objects in the real world,” said Prof. Researchers hypothesized that by investigating pupillary responses of people with aphantasia, they might be able to better understand how visual areas of the brain and ocular reflexes work.Ī recent study compared these pupillary responses in people with and without aphantasia to gain further insight. This condition is known as aphantasia and can begin from birth or develop later on. While some people report the images in their mind feeling almost as vivid as what they perceive in real life, a small percentage of otherwise healthy people cannot produce images in their minds (mental imagery). whether grayscale images are interpreted as the sun or the moon. Another study found that subjective interpretation of visual stimuli also influences pupil size, i.e. One study found that mental imagery may drive pupillary responses to light. Emerging research suggests that higher-order perceptual and cognitive processes may also drive changes in pupil size. Pupils change size to let in the correct amount of light to optimize vision, for example, by contracting in bright conditions and dilating in dark conditions.

The researchers concluded that changes in pupil size could be used to measure the strength of visual imagination.They found that the pupils of those with aphantasia do not respond to visual imagery in the same way as those without.Researchers investigated whether people with aphantasia-an inability for visual imagination-have different pupillary responses to people without the condition.Share on Pinterest The way the pupil dilates in response to stimuli could be an indicator of a person’s visual imagination ability.

Eye with no pupil