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"On the face of it, it is a strange phenomenon: adults who, the moment they lean over to peer into a baby buggy, start babbling a curious baby talk. And it doesn’t just happen to fathers and mothers; it overcomes many people in the same situation. In fact, we all seem to be capable of it, this “de do do do, de da da da.” But what exactly are we saying to our little fellow human beings? What message can be derived from this “de do do do, de da da da?”
The official term for this baby talk is infant-directed speech (IDS). It is a form of speech that distinguishes itself from normal adult speech through its higher overall pitch, exaggerated melodic contours, slower tempo, and greater rhythmic variation. It appears to be a kind of musical language, however it is one with an indistinct meaning and virtually no grammar. For these reasons, I will call it “babble music.” Babies love it, and coo with delight in response to the rhythmic little melodies, which often have the same charm as pop songs like The Police’s “De do do do, De da da da” and Kylie Minoque’s hit “La la la.”
Numerous archives around the world have recordings of musical babble conversations between adults and children. If you listen to several of them, most of the time you won’t be able to understand what’s being said, but you will be able to identify the situation and particularly the mood because of the tone. It will quickly become apparent whether the message is playful, instructive, or admonitory. Words of encouragement such as “That’s the way!” or “Well done!” are usually uttered in an ascending and subsequently descending tone, with the emphasis on the highest point of the melody. Warnings such as “No, stop it!” or “Be careful, don’t touch!” on the other hand, are generally voiced at a slightly lower pitch, with a short, staccato-like rhythm. If the speech were to be filtered out so that its sounds or phonemes were no longer audible and only the music remained, it would still be clear whether encouragement or warning was involved. This is because the relevant information is contained more in the melody and rhythm then it is in the words themselves.
Most linguists see the use of rhythm, dynamics, and intonation as an aid for making infants familiar at a young age with the words and sentence structures of the language of the culture in which they will be raised. Words and word divisions are emphasized through exaggerated intonation contours and varied rhythmic intervals, thereby facilitating the process of learning a specific language. (This, apart from the discussion about which aspects of language are innate.)
Pedagogically speaking, the period during which parents use “babble music” is remarkably long. Infants have a distinct preference for babble music from the moment they are born, only developing an interest in adult speech after about nine months. Before that time, they appear to listen mostly to the sounds themselves. An interest in specific words, word division, and sound structure only comes after about a year, at which time they also begin to utter their first meaningful words. The characterization of IDS as an aid to learning a specific language therefore seems less plausible to me, at least with respect to the earliest months.
An alternative might be to see IDS not as a preparation for speech but as a form of communication in its own right: a kind of “music” used to communicate and discover the world for as long as “real” speech is absent. If you subsequently emphasize the type of information most commonly conveyed in babble music, or rather, those aspects of speech in which infants have the greatest interest during their first nine months, the conclusion must be that babble music is first and foremost a way of conveying emotional information. It is an emotional language that, even without grammar, is still meaningful..."
(A fragment from Musical Cognition: A Science of Listening)
