Easier for whom to read? I am fairly confident that older readers still find that this is so, but it may be that a generation raised on IMHO LOL BFF STFU may not think so...

Years ago I read that comparison studies had been done that compared reading speed and comprehension, but I don't have links to them.

I think most graphic designers believe that sentences set in all caps are harder to read. It's not significant if you're just dealing with a few words (like a headline), but a paragraph in all caps is harder to read.

In fact a trick that designers occasionally do is that if you've got some text that must be included but your client DOESN'T want people to actually read it -- like some bad news in an annual report -- you put it in justified block paragraphs in all caps. You'd think that all caps would draw more attention to it, but lots of folks will give up reading after the first few sentences of all caps.

These days, how accepted is this theory?

Very.

Has there been recent empirical cognitive research that tends to support it or refute it?

People who can barely read never seem to have much trouble with the tiny, tightly-spaced, all-caps text in comic books, which suggests to me that all-caps is quite easy to read. Design pundits make a big deal about the differences in legibility and readability of lowercase and all-caps settings, but the differences are measured in fractions of a second. So if you aren’t typesetting long copy, highway signage, or wayfinding systems then the difference is probably irrelevant. Of course one still needs to consider that many typefaces and a great deal of content will look like crap in all caps no matter how well one typesets it.

another (very long) thread here

Why do CAPITAL LETTERS so annoy us?
http://typophile.com/node/61626

Right James (P)
It's all about context.
Although all-caps is not considered "as readable", that's because the gold standard/acid test of readability is assumed to be books.
But for many other genres of typography, it's just fine.
In fact, all-caps is easier to read when leading is tight; check out the rock band pages in your local entertainment paper.

> It's all about context.

Exactly. Readability is just one of many factors when creating a design. For a book or long article, it's extremely important. For smaller amounts of text, other factors may be a higher priority. And it's not important at all in a psychedelic poster. :)

I just re-read 'A prayer for Owen Meany' by John Irwing. Unfortunately my paperback was set in Melior, and that meant that italics were very hard to distinguish from roman text.

But my point is that Owens' part is written in UPPERCASE, because of his unusual voice. And in my personal opinion, READING UPPER CASE JUST TOOK ME LONGER than lower case with the rest of the book. And that was the point for using UPPER CASE.

Upper case is made for headlines, and lower case is for reading. I believe history has shown it.

But you can always do a Litmus test: set any text with upper and lower case and pick your favourite.

Upper case is made for headlines, and lower case is for reading. I believe history has shown it.

Filocalus would read those as fighting words if he hadn’t been dead for 1600 years.

Want something empirical? Look at the number of books written (in English) and see how many are written in upper case only.

The typeface chosen for British traffic signs was Transport, an upper and lower case 'swiss' design by Jock Kinneir and Margaret Calvert. Nevertheless there is a suggestion that David Kindersley's upper case design solution was rather better. Have a look at this page, particularly the article by Kindersley himself.

Of course, signs and books are completely different animals.

Once a theory is accepted/proven it aint a theory anymore… Which answers your question, I think.

From some other threads:

Arditi, A. & Cho, J. (2007). Letter case and text legibility in normal and low vision. Vision Research, 47(19), 2499–2505.

Pelli, D.G., Tillman, K. A. (2008) The uncrowded window of object recognition. Nature Neuroscience. 11(10) 1129–1136

@ butternick, can you provide a year following which research constitutes "new?" Perhaps you have a list of references, bibliography &c you could share that would allow others to populate it with things that are "new to you?" I am always curious about questions in this field. Do you ask for personal, professional or academic purposes?

@Dunwich Type

People who can barely read never seem to have much trouble with the tiny, tightly-spaced, all-caps text in comic books, which suggests to me that all-caps is quite easy to read.

I suspect it has more to do with conserving space within speech balloons: with the exception of Q, uppercase letters have no descenders, so you can pack a lot more dialogue into a smaller space with all caps. Plus, this approach eliminates having to make decisions about which words should be capitalized, and which need not. And, finally, there's no equivocation about whether or mot a single vertical stroke represents an L or an I...

If you're ever driving on the motorway doing a ton (or whatever the legal limit is for the country you're in :) you'll notice the difference straight away between a fast-approaching, uniform block of uppercase text, and mixed case place names, whose shapes are recognizable many seconds before they are readable. The former releases its information stubbornly, and irritatingly late, and the latter like a close friend. (Oh, and Transport's lowercase l has a little tail to differntiate it from an uppercase I)

Besner, D. (1989). On the role of outline shape and word-specific visual pattern in the identification of function words. The Quarterly Journal of Experimental Psychology A: Human Experimental Psychology, 41(1-A), 91-105.

We can agree that lowercase is easier to read than all caps. The question is why. Two basic themes: A) Our optical neural wiring processes lowercase better (in the same way that our optical wiring is more sensitive to motion than color) or B) we read more lowercase and we're acclimated to it. That's not an issue of cognitive physiology / psychology, just an issue of habit.

@Christopher Dean

I am writing about the legibility of lowercase vs. all caps and one of my editors asked whether "word shape" was an accepted cognitive science theory, and pointed to this

http://www.microsoft.com/typography/ctfonts/WordRecognition.aspx

I understand that the only thing two cognitive psychologists are going to agree on is what the third one is doing wrong. But I was curious as to the currency of the theory.

I think that among most cognitive psych types, both the letterwise and word shape (bouma) recognition models have been superceded by the parallel processing model. See Microsoft article here...

I suspect it has more to do with conserving space within speech balloons…

I agree with all that—and in addition, the larger counters in capital letters are less likely to fill with in when printed on cheap newsprint. I just used that example to show that even under fairly crummy conditions text in all caps is still quite easy to read.

We can agree that lowercase is easier to read than all caps.

I don't agree.
It depends on context, and I gave an example of a context where capitals are easier to read.
Doesn't that count, or are you dealing only in generalizations?

Also the came amount of text set in Cyrillic takes much longer time to read than in Latin letters. Cyrillic lowercase has very few ascenders and descenders so you have to read the text because it is made of longer and shorter blocks, not to quickly scan the shapes of words. Try to watch the same film with English subtitles and then with Russian. Reading Russian you haven't seen the film.

Try to watch the same film with English subtitles and then with Russian. Reading Russian you haven't seen the film.

Except, as you say, you've just watched it.
You seem more attached to myth than logic.

I gave an example of a context where capitals are easier to read. Doesn't that count, or are you dealing only in generalizations?

My question has to do with empirical research, not anecdote.

If the best you can say is that allcaps is readable for short bursts, then you’ve confirmed the thesis that mixed case (conventional upper and lower case, not kRaZy MiXeD-UP caSE) is more readable. The original poster had the wrong question – it isn’t a duel between continuous lower case and continuous upper case. In addition, we are seldom called upon to read “letters.”

@ butternick: Do you consider anything post-Bouma (1973) as "new?"

Bouma, H. (1973). Visual interference in parafovial recognition of initial and final letters of words. Vision Research, 13, 762–782.