Imagine lying on a pristine beach. You are alone, with nothing but a beach chair and the sound of those turquoise waves breaking on the white sand to keep you company. Can you picture it? Yes, but can you actually picture it? Like, do you see the waves moving and breaking, do you see the sand sifting between your toes? Or do you see… nothing?

If you’re like about two percent of the population, you see nothing—a newly-discovered condition known as aphantasia. Discovered in 2015, the study of aphantasia is complicated by the fact that it’s hard to determine whether aphantasia is even real. We can’t look into each other’s minds to see what the other sees.  So when people are asked to imagine things and describe what they see, it’s hard to tell whether they are just seeing the same thing and describing them differently.