Your Pupils Might Reveal How Strong Your 'Mind's Eye' Is
If you find it hard to mentally visualize objects, you're not alone. You might have aphantasia.
Monisha RavisettiFormer Science Writer
Monisha Ravisetti was a science writer at CNET. She covered climate change, space rockets, mathematical puzzles, dinosaur bones, black holes, supernovas, and sometimes, the drama of philosophical thought experiments.
Previously, she was a science reporter with a startup publication called The Academic Times, and before that, was an immunology researcher at Weill Cornell Medical Center in New York. She graduated from New York University in 2018 with a B.A. in philosophy, physics and chemistry.
When she's not at her desk, she's trying (and failing) to raise her online chess rating. Her favorite movies are Dunkirk and Marcel the Shell with Shoes On.
Group 1: You're visualizing a vibrant, ruby-colored fruit like it's living in your mind.
Group 2: You're pondering the concept of an apple without getting any mental imagery.
If you're in the former group, you might wonder whether group 2 just didn't understand the prompt. If you're in the latter, you might find it extremely odd for group 1 to exist at all. And group 2, you might have aphantasia.
For those of you still scratching your head about which category you fall under, the good news is that an experimental startup in Australia is on a quest to find an objective measure of how vivid your imagination is. Having made some serious headway recently, it published a paper about its progress in the journal eLife last month -- but we'll get back to that.
First things first.
What is aphantasia?
Simply put, aphantasia is the inability to form mental images of objects that aren't in your line of sight.
To my fellow group 1 daydreamers, think of it like imagining something you haven't seen before but still know about. You can consider the concept and maybe even rattle off facts about it, but can't "see" the item -- unless you're conjuring a picture of what you suspect it'll look like. For aphantasiacs, it's like this all the time. Forming visceral mental scenery isn't really an option.
"When I close my eyes, I experience only darkness, I have no sensory experience," Neesa Sunar writes in a Psyche article about the phenomenon. And of the aphantasiac lifestyle, "when told to 'imagine a beach,' we assume that it merely means to imagine the concept of a beach. When told to 'count sheep' while falling asleep, we don't realize that people can actually see sheep jumping over a fence."
I'm definitely a solid 5 or 6 on this scale, but a friend of mine claims he's more of a 3 or 4. Some aphantasiacs, who likely fall around a 1 or 2, say they also can't exactly "relive" memories. It's really a spectrum, but aphantasia is estimated to affect between 1% and 3% of the population -- barring the amount of people who don't realize they have it. Still, it remains a relatively unknown subject. It's unclear, for example, who might be most prone to going through life without what's sometimes called a "mind's eye," or whether there's any genetic disposition for the phenomena.
Presumably, these knowledge gaps have persisted because aphantasia isn't quite considered a "disorder" or a "condition" but more of a human characteristic. We all think differently, in essence, so why would this even matter?
That didn't stop scientists from remaining curious.
Here's where last month's research study comes in -- and why it might be a pretty big deal.
A team from the University of New South Wales Sydney basically found a way to verify whether someone has aphantasia by measuring pupil dilation. They're part of the Future Minds Lab, an experimental startup aimed at decoding the psychological phenomena.
"This really is the first biological, objective test for imagery vividness," Joel Pearson, a professor and senior author of the paper, said in a statement on the study.
After studying the pupillary reflexes of 42 study participants, some self-reported aphantasiacs, they saw non-aphantasiacs' and aphantasiacs' pupils clearly dilating when physically looking at objects in front of them. However, only non-aphantasiacs' pupils reflected a similarly strong response when mentally visualizing those items.
"While it was already known that imagined objects can evoke so-called 'endogenous' changes in pupil size, we were surprised to see more dramatic changes in those reporting more vivid imagery," Pearson said.
But Pearson and fellow researchers didn't stop there. They also wanted to disprove the stigma that aphantasiacs aren't trying hard enough to conjure mental images -- aka, prevent group 1 from judging group 2's inability to do what the first group easily can.
The team asked both the vivid visualizers and idea conceptualizers to imagine four objects simultaneously, instead of just one. In doing so, the non-aphantasiacs had an expected pupillary response, and surprisingly, even the aphantasiacs started exhibiting pupil dilation.
Aha. Aphantasiacs truly are trying to visualize stuff, but their pupils might only give their efforts away when they're working super hard.
As Pearson puts it, "For the first time, we have strong biological evidence that those with aphantasia are really trying to create a mental image, putting to rest claims that they may simply not be attempting to create a mental image."
The idea of measuring human minds forces us to visit a number of fascinating philosophical questions surrounding cognition. If we can detect mental imagery, perhaps we can solve other mysterious psychological puzzles.
Likewise, epistemologists are interested in unveiling whether our thoughts are directly connected to our conscious experience -- perhaps "picturing an apple" would be a wildly different or richer task for someone who can see color than for someone who can't.
For now, though, understanding the intricacies of aphantasia is a great place to start, especially because knowing whether we have it can be a rewarding gateway to introspection.
"It reminds us that just because I remember or visualize something one way, doesn't mean everyone does," Rebecca Keogh, a researcher at Macquarie University and co-author of the study, said in a statement.
"This really is an exciting time," Pearson said. "We are very close to having objective, reliable tests for extreme imagery, aphantasia and hyperphantasia -- extremely strong visual imagery -- that could be scaled up to run online for millions of people everywhere."
It's human nature to wonder about questions like whether you're part of group 1 or group 2. It's also pretty fun.