It should not have come as a surprise. It seems impossible that I did not know. I had been trained in the fraud that is learning styles, I was working in a school, I was an English teacher. You would have thought it might have come up.

But no. I lived in ignorance for so many years. When I asked students to picture a scene, or to imagine the appearance of a character, or to visualise a room, I always assumed that they saw exactly what I did. Which was pretty much...well...nothing.

It was only when I read an article online, by chance, that I learned that I was very wrong. Most people, it turned out, see a bit more than nothing when they visualise something cognitively. In fact, they see a lot more. And rather than my brain being like everyone else’s, I discovered that I was in the minority: one of a small group of humans with a condition called aphantasia.

Aphantasia is relatively unknown. Those who have it are unable to voluntarily create mental images, and it is believed that 2 per cent of the population have some mental blindness of this type (so it’s likely you will have taught pupils with the condition).

The term aphantasia was coined as recently as 2015 by Adam Zeman of the University of Exeter. However, the phenomenon of not having a “mind’s eye” has been recognised since the 1880s. In a famous case, psychologist Francis Galton asked his subjects, including his half-cousin Charles Darwin, to imagine themselves at the breakfast table. Some found this task easy, but others drew a complete blank.

My first response when I realised that I had the condition was shock. And, to be honest, I felt a bit broken. While others had access to this rich kaleidoscope of colours and images swirling around their heads, I had nothing.

Well, pretty much nothing - it isn’t quite a blank space in my head.

To give you an idea of what it is like, we can use the example of a horse. I always use a horse as a comparison because it is a fairly universal and standard thing to think of - people know what a horse looks like - and I have spent a fair amount of time around these animals, drawing them and thinking about them as a child.

As hard as I try, I can only “see” flashes of images, fragments of the whole. I see a bit of an ear, the end of a nose, maybe their neck. My horse is definitely not cantering across the plains.

My other half, however, not only pictures the horse in full-colour motion, but can add various hats, plait its mane, dress it in cowboy boots and make it do the Macarena. In space.

In those early days of recognising what I had lived so long without, I felt robbed, especially as an avid reader. While others can lose themselves in the landscapes of the Brontës or wander around Middle Earth, I mostly live on the page. I can imagine - it’s not like I can’t understand the vision of the writer - I just happen to do it with words or feelings instead.

But after the period of sulking, I hit the research hard.

Like other aphantasics, it turns out that I also don’t imagine smells or tastes, something else my other half enjoys partaking of while I sit there “knowing” how a pizza tastes and smells but not actually tasting or smelling anything.

Also like other aphantasics, I get lost easily because I can’t hold maps in my head, relate the visual on a map with my surroundings or have much of a sense of direction. I have no mental images to link it to.

And like other aphantasics, I don’t imagine sounds, so I don’t suffer from earworms, and in sleep I dream in vivid cinematic images, full movie mode, which I can rewind, edit and reframe at will.

Clearly, much more research needs to be done to unpick this condition, but I have stopped worrying as much. After all, I discovered that I am in good creative company, with many Pixar artists reportedly being aphantasic. Creativity is clearly not hampered by thinking in this way, and early research indicates that aphantasic people can recreate complex visual images from memory more effectively than their counterparts.

So, rather than moping, I wanted to try to take something from this that could help my students.

The first thing was obvious: I was now aware that there will be students in my classes who are aphantasics, too.

The second thing was more a reminder than a revelation: my own condition was a good example of how different brains can function very differently. It is easy to forget that in the classroom and when you are constantly reading research about how the brain works.

For example, we may have students who experience synaesthesia (where senses are combined, for example smelling a sound) and prosopagnosia (being unable to recognise faces) and many other ways of thinking that we may not even be aware of. Those differences could be crucial in how that pupil understands the lesson.

And finally, those things that we take for granted, such as concept maps and graphic organisers, which we talk up as universally useful - guess what? For many pupils, it will be incredibly difficult to employ them in the learning process.

Have these revelations changed my teaching? Certainly. I take a lot less for granted, I check for understanding more, I assume less. I am careful to make my instructions more specific and I provide more detailed frames for visual strategies.

None of these tweaks is because I may have aphantasics in my classroom. Rather, aphantasia has simply been a timely reminder that these things are important to every child, not just those who might have a learning difference or a learning disability (aphantasia, by the way, is the former, not the latter).

Now you have had that reminder, too. I hope it stays with you next time you are in the classroom. I would say I can imagine the scene, but, well …

Zoe Enser is lead English adviser for Kent

This article originally appeared in the 18 September 2020 issue under the headline “I was blind in my mind’s eye - I can see that now”