Julie Sedivy is the lead author of Sold on Language: How Advertisers Talk to You And What This Says About You. She contributes regularly to Psychology Today and Language Log. She is an adjunct professor at the University of Calgary, and can be found at juliesedivy.com and on Twitter/soldonlanguage. What’s the most exotic, strange-sounding language you’ve ever heard? I recently popped this question to a group of English speakers at a cocktail party. Norwegian and Finnish were strong contenders for the title, but everyone agreed that the prize had to go to African “click languages” like the Bantu language Xhosa (spoken by Nelson Mandela) or the Khoisan language Khoekhoe, spoken in the Kalahari Desert. Conversations in such languages are liberally sprinkled with clicking sounds that are made with a sucking action of the tongue, much like the sounds we might make when spurring on a horse or expressing disapproval. You may have been introduced to one of these click languages spoken by Kalahari Bushmen in the 1980 film

The Gods Must be Crazy.

Below is an example, and if you’d like to try your hand at making Xhosa click sounds, you can find a quick lesson here. To English ears, Xhosa speech often comes across a bit like highly-skilled beatboxing, mixing recognizeable speech with what sounds like the clacking of objects striking each other. My cocktail party friends wanted to know “How do they click and talk at the same time?” To a native speaker of Xhosa, this is a really weird question, much like asking “How do they make the consonants t or p and talk at the same time?” The late African singer Miriam Makeba, in introducing this 1979 performance of her famous “Click Song,” put it like this: “Everywhere we go, people often ask me ‘How do you make that noise?’ It used to offend me, because it isn’t a noise, it’s my language.” If clicks do sound like exotic noises to you, it might surprise you to know that there’s nothing especially difficult about making click sounds in speech---they’re easily mastered by toddlers who still struggle making truly difficult sounds like s and z. And it might really surprise you to learn, as found in a recent study by Melissa Wright at Birmingham City University, that as an English speaker, you likely riddle your own speech with click sounds, using them much more frequently and systematically than just the occasional “tsk” of disapproval. If that’s so, why on earth do the African clicks sound so strange to English speakers, to the point of being un-language-like? When it comes to the perception of speech sounds, your brain cares as much about how sounds function in a language than about their actual physical properties, so the same acoustic input can be interpreted very differently by the brain depending on its role in a language. In a language like Xhosa, clicks belong to the language’s inventory of consonants, right along with garden-variety speech sounds like t, p, or s that make up the basic building blocks of words. So the clicks acquire a perceptual status that is very similar to these more ordinary sounds. But Melissa Wright found, after combing through eighteen hours of recorded telephone conversations, that for English speakers, clicks were used for a very different purpose, namely as a conversational signal that the speaker was shifting the topic. You might think of them as the oral equivalent of a paragraph break marking a discontinuity in the conversation. For example, here’s a snippet of dialogue from Wright’s tapes: Nor: You leave Wincanton about three o’clock and get back about two in the morning…Les: Oh.Nor: …and work full-time on top of that.Les: Oh dear.Nor: But it’s a lot easier now huh.

Les: Yes. I’m sure. Hm. [click] okay well I’ll tell Gordon and uhm, I’m sure he was going to give you a ring anyway.

So, English speakers use clicks as a systematic linguistic tool to help organize their conversations rather than as the building blocks of words. But how would this explain why we don’t hear these conversational clicks as if they were the auditory equivalent of colliding objects, whereas that’s how we might experience the African clicks? And how is it that we hear African clicks as “noises” whereas speakers of a language like Xhosa hear these very same sounds as normal speech sounds? For a clue, it makes sense to look at what happens in the brain when languages take different approaches to carving up the division of labour of sound. Pitch is probably the best-studied case. In a language like Mandarin, pitch is essentially used as a third type of acoustic building block for words, along with consonants and vowels. In English, producing one consonant instead of another usually results in saying a completely different word---try, for instance: pan, ban, can, man, tan, and Dan. But varying the pitch on a word like pan doesn’t make it into a different word. In Mandarin, though, the same string of consonants and vowels---for instance, the simple sequence ma---can mean different things depending on the pitch contour you lay over it. Say it with a high tone, and you’ve uttered “mother”, with a rising tone, and you’ve said “hemp”, with a low falling tone, you mean “horse”, and with a high falling tone, you’ve made a scolding sound. (You can hear the four different versions here, courtesy of the UCLA Phonetics Lab.) To many speakers of English, this seems like a preposterous way to run a language; learning to hear and produce the differences between these tones can be devilishly hard and opportunities for comedic or offensive errors lurk around every corner. But it’s funny. There’s nothing inherently tricky for English speakers about controlling pitch in language. We do it all the time. For example, think of the various ways in which you might tweak the pitch on a word like so; you’d say it with different tones depending on whether you’re prodding a friend for more information about her date last night, thinking aloud while solving a problem, briskly wrapping up an argument to move on to the conclusion, and so on. (If you’re not fully convinced, have a look at this Ford Focus TV commercial, whose dialogue consists entirely of the single word dude, repeated with a variety of different tones). Producing the wrong tone in the wrong context would sound bizarre, and it would definitely change its communicative effect---nevertheless, it still wouldn’t change the identity of the word you’ve just uttered. And this turns out to be a fundamental difference that has consequences for how English and Chinese brains process information about linguistic tone. For all brains, attending to pitch in a non-linguistic context (for example, in discriminating among various musical tones or patterns) usually involves heightened activity in the right hemisphere of the brain. But many language tasks show higher levels of activity in the left hemisphere. So what happens when people have to pay attention to different tonal patterns incorporated into words? It depends on which language they speak. When Mandarin speakers listen to sets of Mandarin words that are distinguished by tone alone, they tend to show concentrated brain activity in the left hemisphere, in regions that are typically linked with bread-and-butter language processing tasks. But when English speakers hear exactly the same stimuli, they tend to process them in the right hemisphere, where people usually process tones used non-linguistically, like in music. Even though tone is communicatively important for English speakers, it’s not treated as woven into the very fabric of language. But for Mandarin speakers it is. This may give us some insight into why, despite being regular clickers ourselves, many of us can’t help but hear African clicks as noise-like when they’re used in words where we expect consonants to be. Our brains have plenty of experience in hearing clicks---just not in that particular role. It may also explain why speakers of click languages are bemused by our inability to hear them as plain old consonants.