Try to imagine an apple floating. Now try to rotate it and look at it from every side and see if it has any blemishes on it. Can you do it? Can you see the apple clearly? Well some people can’t.
Sounds impossible but it’s more common than you’d think.
Some people can see the apple clearly, like looking at a picture or watching a video, others have a very poor image of it. The small proportion of people that have reported having no visual experience of things are otherwise healthy individuals.
No matter how hard they try to visualize the apple, they can’t do it. It’s like their minds are completely blind. This phenomenon is called- congenital aphantasia.
There have been stories of people who didn’t know that almost every person is able to imagine things. Even one of the creators of Firefox, Blake Ross, realised he was different when he read about a man who lost his ability to imagine after surgery.
Many people have experienced an epiphany just like Ross did. They all thought no one was able to picture visual imagery.
Everyday tasks, such as remembering something from the past, navigation and facial recognition require visual imagery.
Aphantasic people have indicated that they do remember things from the past but they do not experience them in the same way as other people do. They describe their memories as a conceptual list of things that have happened but they don’t see a movie reel playing in their mind.
Ross described his memory of a beach. He knows there’s sand and water and other facts about the beach but he can’t visualize the exact beach he’s been to, he can’t even create an image of a beach in his mind.
This phenomenon has been discovered in the late 1800s when British scientist Sir Francis Galton conducted research asking the general population and his colleagues about their internal imagery.
But the problem in these self-reports Is that they are subjective. They depend on the mental process called- Introspection. Some researchers have suggested that aphantasia is just a case of poor introspection. They think aphantasics are creating the same images in their mind like everyone else, but they can’t describe them the same way. Another idea is that they lack internal consciousness of the images they create.
Binocoular rivalry is a technique used to assess visual imagery objectively without having someone to describe what they imagine. This is induced by wearing 3D glasses where one eye sees a red image and the other a green one. We can’t see both images at once so our brain constantly switches from one to another.
We can influence which of the colored images someone will see in the binocular rivalry display by getting them to imagine one of the two images beforehand.
For example if we ask the person to imagine a red image, he is more likely to see the red image once he’s put on the 3D glasses. The stronger his imagery is, the more frequently he will see the image he imagined. This is used as a measure of objective visual imagery.
In this study, a few self-described aphantasics were told to imagine either a red circle with horizontal lines or a green circle with vertical lines for six seconds before giving them the 3D glasses and presenting them the binocular rivalry display.
Then they were told to indicate which picture they saw. This process was repeated close to 100 times.
This study has helped us discover that aphantasics are truly unable to form a mental image. They do not have a problem with introspection, they simply have no visual imagery.
Why are some people mind blind?
Another research in the general population has shown us that visual imagery involves brain activity which spans from the frontal cortex to the visual areas in the back of the brain.
It is proposed in current theories that when we imagine something we try to reactivate the same activity in our brain as when we saw the image before. And the better we are at doing this, the stronger our imagery is.
Aphantasic people can not reactivate the traces enough to make them experience visual imagery, or they use a completely different network when trying to imagine something.
But all of this might not be such a bad thing after all as people that are aphantasic tend to live more fully in the moment. And they are less likely to have and addiction, cravings or anxiety disorders such as PTSD.