Basically, it says that the words you learn could have an impact on the colors you see. It included some studies they did with the people in the Himba tribe in Northern Namibia.
The English language has eleven color categories. Reds, blues, greens, browns, yellows, etc. In the Himba tribe, they only have FOUR.
Zoozu= dark colors, including red, some blues, some greens, and purple
Vapa= white and some yellows
Borou= some greens and blues
Dumbu= different greens, reds, and brown
Why is this weird? They did a test, showing participants a ring of squares where all but one of the colors were the same. When the colors were all green, with one very slightly different, English-speakers had a hard time figuring out which green was different. This is an image I recreated, based on what I remember seeing. Can you tell which is different?
Chances are, unless you have been trained in a profession where you have very specific names for colors--- such as an artist, a printer, a designer, etc.--- you'll have a little trouble picking out which one is different from the others without looking at it for quite a while, if ever.
With the Himba tribe, the other green had a different NAME, so they could pick it out instantly.
On the flip-side, though, when the ring of colors were all green with one blue, we can pick it out the second it was put on the screen.
Easy peasy, right? When two colors have different names, we can pick out the difference immediately. However, the two colors had the same name among the Himba, so they couldn't tell the difference. Fascinating, no?
It's not that their eyes work any differently than our eyes work. It's simply because the words we use to categorize things really changes the way we SEE things.
When we have categories to put things in, we can very quickly order the things that we see.
And, of course, it doesn't just work with the colors that we see-- Characters and setting are the same way. When we read about someone or some place, our mind immediately categorizes them (not always in the right category, of course). The brain orders what it sees. And that, my friends, can be used to our advantage or our disadvantage. A reader WILL do it, whether we want them to or not. If we're aware of it when we first introduce a scene, it can be to our advantage. A few carefully chosen words can set a scene by placing it in a well-known category, which is especially helpful when it's a part you don't want bogged down by description. If we're aware of it when we're introducing a character, helping the reader put them into a category with the words we choose can get them thinking exactly what we want them to think about that character (whether it's a correct assumption on their part, or whether we want them to learn it's incorrect later).
As readers and writers, we already know that words are pretty darn powerful. That's what we expect when we read or write a book-- to transport us fully, completely, powerfully somewhere else.
Isn't it amazing that even A SINGLE WORD can do the same thing?
(And in case you wanted to know if you were right, here's the answer to which square is different on the all green one:)