Brains are strange.

While sitting in a coffee shop this afternoon, as so often happens in coffee shops, I overheard a conversation. It started off simply, just the barista giving a customer directions to I-5, but then it took an interesting turn. The customer, a middle-aged woman, stopped the barista and said, "I can't visualize anything. So I'll go down Stone Way and the coffee shop will be on my left?"

Can't visualize anything? That caught my attention. I kept listening and found out that something happened 20 years ago that caused brain damage, and ever since then she hasn't been able to visualize anything. She can't create mental pictures. When someone gives you directions, even if you've never been where you're going before, your brain takes the words being said and turns them into physical directions for you to make a mental picture of, so you can keep track of where you're going. Her brain can't do that anymore.

Talking to the barista, she said, "I can look at you right now and close my eyes and not be able to think of what you look like." She has clearly been explaining this phenomenon to people for many years, because she's full of examples of how it applies. She explained that while she can read non-fiction, she lost the ability to read fiction because it's extremely hard to keep track of a story if you can't visualize it.

I've heard of many strange brain injuries (I <3 Oliver Sacks), but the implications of not being able to visualize anything had never occurred to me before. It makes perfect sense though. If I were to tell you a story about a very far away planet, but not tell you any details to create a mental picture of the planet, the story probably wouldn't make any sense, because you would have no context for it. The same thing applies to movement. If I were to tell you to close your eyes and imagine all the steps involved in standing on your head, and you had never tried it before, making a mental picture of those steps would be extremely difficult.

Huh. Brains are strange.