ALL-CAPS: Harder to Read?

Susan Weinschenk, Ph.D. wanted to write an article about why it's harder to read text set in all-caps than text set as mixed case. The argument for this has centered around how people read words — recognizing a word shape from its letters, whereas an all-caps word has no unique shape. She started to research this idea for her article but could find little to support it. Her article, 100 Things You Should Know About People: #19 — It's a Myth That All Capital Letters Are Inherently Harder to Read, outlines a different method for how letters and word shape work to make it easier for people to read.

In her research she found that people respond to letters they recognize and anticipate, essentially recognizing letter sequences within a word, not the shape of the word. Because of the eye's jumpy nature, thanks to saccades (great article in an old Scientific American issue), your eyes essentially leap ahead a bit and leverage peripheral vision to recognize letters and, as a result, words. A reader can generally pick up 15 letters at a time this way.

From here she argues that text set in all-caps isn't harder to read by its nature, readers just don't have much experience with it. Readers will still take longer to read it, so there is no reason to assume the difference in speed is a myth. They can be trained, however, to bring that speed up.

There is a contrary viewpoint to this, however. A dyslexic writer at the Daily Kos has posted her own plea for writers (blog commentors, etc.) to avoid using all-caps in their comments, posts, articles, etc. This writer claims that she relies on the shape of a word:

However letters mean little to me still I read by a form of pictogram system. Every word has a shape therefore I read the word by its visual form and not its content. [...] [W]hen someone writes in all caps I just cannot see the shape of the intended word [...] I know quite a few dyslexics of varying severity and know that word form is important to many.

In short, while it may be possible to train a reader to recognize all-caps, you certainly won't train your users to do it. Nor do you want to be the application, web site, book, journal, etc. that drives people away in such a misguided attempt. Even if you did manage to train your readers, you would clearly be leaving some selection of dyslexic users out in the cold, perhaps not to return (or worse, to recommend against reading to all their friends).

Architects and engineers who are used to reading all-caps may be excluded from the first part, but I am in no position to form a focus group to test that theory for the scope of this brief piece.