Those fast-talking Japanese! And Spanish!

It is the universal experience of anyone having a first serious encounter in a language he or she is learning: "Those people talk so fast I will never be able to understand them, let alone hold my own in a conversation."

The learner timidly poses a carefully rehearsed question about the availability of tickets for tonight's performance or directions to the museum or whatever, and the response all but gallops out of the mouth of the native speaker like a runaway horse.

Now researchers at the University of Lyon in France have presented findings that provide language learners some validation for their feelings – but only some. The team found that, objectively, some languages are spoken faster than others, in terms of syllables per minute. But there's a trade-off: Some languages pack more meaning into their syllables.

The key element turns out to be what the researchers call "density."

Time magazine published a widely reproduced article on the Lyon research, which originally came out in Language, the journal of the Linguistic Society of America. The team in Lyon recruited several dozen volunteers, each a native speaker of one of several common languages: English, French, German, Italian, Japanese, Mandarin Chinese, or Spanish. Vietnamese was used as a sort of control language.

The volunteers read a series of 20 different texts in their respective native tongues into a recorder. The researchers then counted all the syllables in each of the recordings to determine how many syllables per second were spoken in each language. That's a lot of counting.

Then they analyzed all these syllables for their information density. To mention Time's examples: "A single-syllable word like bliss, for example, is rich with meaning – signifying not ordinary happiness but a particularly serene and rapturous kind. The single-syllable word to is less information-dense. And a single syllable like the short 'i' sound, as in the word jubilee, has no independent meaning at all."

Here's where Vietnamese comes in: It turns out to be the gold standard for information density. Who knew? The researchers assigned an arbitrary value of 1 to Vietnamese syllables, and compared other syllables against that standard.

English turns out to have a density of .91 (91 percent as dense as Vietnamese, in other words) and an average speed of 6.19 syllables per second. Mandarin is slightly denser (.94) but has an average speed of 5.18, which made it the slowest of the group studied.

At the other end of the scale were Spanish, with a density of .63 and a speed of 7.82, and Japanese, with a density of only .49 but a speed of 7.84.

So what makes a language more or less dense? The number of sounds, for one thing. Some languages make do with relatively few consonants and vowels, and so end up with a lot of long words: Hawaiian, for example, with 13 letters.

English, on the other hand, has a relatively large number of vowels – a dozen, although that varies according to dialect. Chinese uses tones, which help make it a "denser" language. And some languages use more inflections – special endings to indicate gender, number, or status – which English, for instance, largely dispenses with.

The researchers concluded that across the board, speakers of the languages they studied conveyed about the same amount of meaning in the same amount of time, whether by speaking faster or packing more meaning into their syllables.