3.5 Language

No other species has anything approaching the neurons and networks that support the 6000 or so human languages. The human ability to communicate, even at age 2 years, far surpasses that of full-grown adults from every other species. This includes dolphins, ravens, and chimpanzees, all with much better communication mechanisms than was formerly believed.

Here we describe the specific steps in human language learning, “from burp to grammar” as one scholar put it (Saxton, 2010). We then ask: How do babies do it?

The Universal Sequence

The timing of language acquisition varies; the most advanced 10 percent of 2-year-olds speak more than 550 words, and the least advanced 10 percent speak fewer than 100 words—a fivefold difference (Merriman, 1999). But, although timing varies, the sequence is the same worldwide (see At About This Time). Even children who are deaf who become able to hear before age 3 (thanks to cochlear implants) follow the sequence (Ertmer et al., 2007).

Listening and RespondingInfants who can hear begin learning language before birth, via brain connections. They prefer the language their mother speaks over an unheard language; newborns of bilingual mothers respond to both languages and differentiate between them (Byers-Heinlein et al., 2010).

Newborns look closely at facial expressions, apparently trying to connect words and expressions, to understand what is being communicated. By 6 months, infants can tell whether a person is speaking their native language or not, just by looking at the person’s mouth movements (no sound) (Weikum et al., 2007). The ability to distinguish sounds and gestures in the language (or languages) of caregivers improves over the first year, while the ability to hear sounds never spoken in the native language deteriorates (Narayan et al., 2010).

Adults everywhere use higher pitch, simpler words, repetition, varied speeds, and exaggerated emotional tones when they speak to infants (Bryant & Barrett, 2007). This special language form is sometimes called baby talk, since it is talk directed to babies, and sometimes called motherese or parentese, since mothers and other caregivers—including fathers and siblings—universally speak it. In fact, all of these may be misleading terms; scientists prefer the more formal designation, child-directed speech.

Same Situation, Far Apart: Before Words The Polish babies learning sign language (left) and four-month-old Claire, from Victoria, British Columbia (right) are all doing what babies do: trying to understand communication long before they are able to talk.

JANEK SKARZYSNKI/AFP/GETTY IMAGES/NEWSCOM
DANIEL GERMAN

No matter what term is used or who is speaking it, child-directed speech captures infant attention and thus fosters learning.

Sounds are preferred over content. Infants like alliteration, rhymes, repetition, rhythm, and varied pitch (Hayes & Slater, 2008; Schön et al., 2008). Think of your favourite lullaby (itself an euphonious word). All infants listen to whatever they can and appreciate the sounds they hear. Even music is culture-specific: 4- to 8-month-olds seem to like their own native music best (Soley & Hannon, 2010).

BabblingAt first, babies mostly listen. By 6 months they start practising sounds, repeating certain syllables (ma-ma-ma, da-da-da, ba-ba-ba), a phenomenon referred to as babbling. Responses from other people encourage babbling (this is the age of “making interesting events last”).

Who is Babbling? Probably both the 6-month-old and the 27-year-old. During every day of infancy, mothers and babies communicate with noises, movements, and expressions.

ARIEL SKELLEY/GETTY IMAGES

Toward the end of the first year, babbling begins to sound like the infant’s native language; infants imitate what they hear in accents, cadence, consonants, and so on. Gestures also become more specific, with all babies (deaf as well as hearing) expressing concepts with gestures sooner than with speech (Goldin-Meadow, 2006).

One early gesture is pointing, typical in human babies at 10 months. Pointing is an advanced social gesture that requires understanding another person’s perspective. Most animals cannot interpret pointing; most 10-month-old humans can look toward the place another person is pointing at and can point themselves, even at the place where an object should be but no longer is (Liszkowski et al., 2009).

First WordsFinally, at about 1 year, the average hearing baby utters a few words, although some hearing babies do not begin to talk until about 18 months. Caregivers usually understand the first words before strangers do, which makes it hard for researchers to pinpoint exactly what a 12-month-old can say.

Spoken vocabulary increases gradually (perhaps one new word a week). However, 6- to 15-month-olds learn meanings rapidly; they understand about 10 times more words than they can say (Schafer, 2005; Snow, 2006). Initially, the first words are merely labels for familiar things (mama and dada are common), but each can convey many messages. Imagine meaningful sentences encapsulated in “Dada!” “Dada?” and “Dada.” Each is a holophrase, a single word that expresses an entire thought.

Careful tracing of early language from the information-processing perspective finds periods when vocalization seems to slow down before a burst of new talking, as perception and action are interdependent (Pulvermüller & Fadiga, 2010). This means that sometimes, with a new perceptual understanding, it takes time for verbal output to reflect that neurological advance. This slowdown before a language spurt is not evident in every infant, but many seem temporarily quieter before a burst of new words (Parladé & Iverson, 2011).

Once vocabulary reaches about 50 expressed words (understood words are far more extensive), it builds rapidly, at a rate of 50 to 100 words per month, with 21-month-olds saying twice as many words as 18-month-olds (Adamson & Bakeman, 2006). This language spurt is called the naming explosion because many early words are nouns (Waxman & Lidz, 2006).

Show Me Where Pointing is one of the earliest forms of communication, emerging at about 10 months.

IMAGE SOURCE/GETTY IMAGES

Cultural Differences

Early sequence and sounds of languages are universal, but there are many differences that soon emerge. For instance, about 30 languages of the world use a click sound as part of spoken words; infants there become adept at clicking. Similarly, the rolled “r,” the enunciated “l” or “th,” and the difference between “b” and “v” are mastered by infants in some languages but not others, depending on what they hear.

Although all new talkers say more nouns than any other parts of speech, the ratio of nouns to verbs varies from place to place. For example, by 18 months, English-speaking infants use relatively more nouns but fewer verbs than Chinese or Korean infants do. Why?

One explanation goes back to the language itself. Mandarin and Korean are “verb-friendly” in that verbs are placed at the beginning or end of sentences, which makes them easier to learn. In English, verbs occur in various positions within sentences, and their forms change in illogical ways (e.g., go, gone, will go, went). This irregularity makes English verbs harder to learn than nouns.

An alternative explanation considers the entire social context: Playing with a wide range of toys and learning about dozens of objects are crucial in North American culture, whereas East Asian cultures emphasize human interactions—specifically, how one person responds to another.

Accordingly, North American infants are expected to learn to name many objects, whereas Asian infants are expected to act on objects and respond to people. Thus, Chinese toddlers might learn the equivalent of come, play, love, carry, run, and so on before Canadian ones (Chan et al., 2009). This is the result of experience, not genes. A toddler of Chinese ancestry growing up in an English-speaking Canadian home has the learning patterns of other English-speaking toddlers.

A simpler explanation is that young children are sensitive to the sounds of words, with some sounds more salient than others. Verbs are learned more easily if they sound like the action (Imai et al., 2008), and such verbs may be more common in some languages than others.

In English, most verbs are not onomatopoeic, although perhaps jump, kiss, and poop—all learned relatively early on—are exceptions. The infant preference for sounds may be one reason why many English-speaking toddlers who have never been on a farm nonetheless know that a cow says “moo” and a duck says “quack.”

Putting Words TogetherGrammar includes all the methods that languages use to communicate meaning. Word order, prefixes, suffixes, intonation, verb forms, pronouns and negations, prepositions and articles—all of these are aspects of grammar, all varying by whatever language the infant hears (Saxton, 2010).

Grammar can be discerned in holophrases but becomes obvious between 18 and 24 months, when two-word combinations begin (Tomasello, 2011). For example, in English, “Baby cry” and “More juice” follow the proper word order. No child asks, “Juice more,” and already by age 2 children know that “cry baby” has an entirely different meaning than “Baby cry.” Soon the child combines three words, usually in subject–verb–object order in English (for example, “Mommy read book”), rather than any of the five other possible sequences of those words.

Young children can master two languages, not just one. The crucial variable is how much speech in both languages the child hears. Listening to two languages does not necessarily slow down the acquisition of grammar, but “development in each language proceeds separately and in a language specific manner” (Conboy & Thal, 2006). In Canada, where English and French are the official languages, many infants acquire both. This is referred to as bilingual first language acquisition (BFLA). Statistics Canada estimates that in 2006, almost 18 percent of the population was fluent in both French and English (Corbeil & Blaser, 2009).

A review by Fred Genesee of McGill University is one of several recent studies to explore whether BFLA in any way strains a child’s language-learning ability or leads to delays in the language-acquisition process (Genesee, 2009). As Genesee (2008, 2009) points out, this type of research is important because of the number of people—including some parents, teachers, speech pathologists, and educational policy-makers—who fear that BFLA may have negative impacts on a child’s ability to learn either language properly. In their research, Genesee and other scientists have debunked three common misconceptions:

1. Children who are bilingual have greater difficulty in learning grammar than children who speak one language. In fact, bilingual children have similar rates of language development as monolingual children, at least in their dominant language (Nicoladis & Genesee, 1996; Paradis & Genesee, 1996). (Note that for various reasons, most dual-language learners become more proficient in one language than the other [Genesee, 2009].)
2. Children who are monolingual speak their first words sooner and learn words faster than children who are bilingual. Again, research shows that monolingual and bilingual children produce their first words at about the same time. They also show similar rates in the growth of their vocabulary (Pearson et al., 1993; Pearson & Fernandez, 1994).
3. Dual-language learners face more communication challenges than monolingual children. Actually, bilingual children have about the same number of communication challenges as children who speak only one language. Interestingly bilingual children often become more skilled in interpersonal communications at an earlier age since they switch between languages depending on context and the preferences of the person they are speaking to (Vihman, 1998).

Indeed, some evidence suggests that children are statisticians: They implicitly track the number of words and phrases and learn those expressed most often. That is certainly the case when children are learning their mother tongue; it is probably true when learning a second language as well (Johnson & Tyler, 2010).

Bilingual toddlers soon realize differences between languages, adjusting tone, cadence, and vocabulary when speaking to a monolingual person. Most bilingual children have parents who are also bilingual; hence, these children mix languages because they know their parents will understand.

Note that mixing languages is a cultural adaptation, not a sign of mental deficiency. In fact, bilingual children and adults seem to have a cognitive advantage over monolingual people, as noted in Chapter 5.

How Do They Do It?

Worldwide, people who are not yet 2 years old already speak their native tongue. They continue to learn rapidly: Some teenagers compose lyrics or deliver orations that move thousands of their co-linguists. How is language learned so easily and so well? Answers come from three schools of thought, one emphasizing learning, one emphasizing culture, and the third stressing evolution.

Theory One: Infants Need to Be TaughtThe seeds of the first perspective were planted more than 50 years ago, when the dominant theory in North American psychology was behaviourism, or learning theory. The essential idea was that all learning is acquired, step by step, through association and reinforcement. Just as Pavlov’s dogs learned to associate the sound of a tone with the presentation of food (see Chapter 1), behaviourists believe that infants associate objects with words they have heard often, especially if reinforcement occurs.

B. F. Skinner (1957) noticed that spontaneous babbling is usually reinforced. Typically, every time the baby says “ma-ma-ma-ma,” a grinning mother appears, repeating the sound as well as lavishing the baby with attention, praise, and perhaps food. Skinner believed that most parents are excellent instructors, responding to their infants’ gestures and sounds, thus reinforcing speech (Saxton, 2010).

The core ideas of this theory are:

• parents are expert teachers, although other caregivers help
• frequent repetition is instructive, especially when linked to daily life
• well-taught infants become well-spoken children.

Behaviourists note that some 3-year-olds converse in elaborate sentences; others just barely put one simple word with another. Such variations correlate with the amount of language each child has heard. Parents of the most verbal children teach language throughout infancy—singing, explaining, listening, responding, and reading to their children every day, even before 1 year of age (Forget-Dubois et al., 2009) (see Figure 3.9).

FIGURE 3.9 Maternal Responsiveness and Infants’ Language Acquisition Learning the first 50 words is a milestone in early language acquisition, as it predicts the arrival of the naming explosion and the multiword sentence a few weeks later. Researchers found that the 9-month-old infants of highly responsive mothers (top 10 percent) reached this milestone as early as 15 months. The infants of nonresponsive mothers (bottom 10 percent) lagged significantly behind.

Theory Two: Culture Fosters Infant LanguageThe second theory arises from the sociocultural reason for language: communication. According to this perspective, infants communicate because humans are social beings, dependent on one another for survival and joy. Each culture has practices that further social interaction; talking is one of those practices.

It is the emotional messages of speech, not the words, that are the focus of early communication, according to this perspective. In one study, people who had never heard English (Shuar hunter–gatherers living in isolation near the Andes Mountains) listened to tapes of North American mothers talking to their babies. The Shuar successfully distinguished speech conveying comfort, approval, prohibition, and attention, without knowing any of the words (Bryant & Barrett, 2007). Thus, the social content of speech is universal, which is why babies learn whatever their culture provides.

For example, many 1-year-olds enjoy watching television and videos, but the evidence implies that they learn from it only when adults are actively involved in teaching. In a controlled experiment, 1-year-olds learned vocabulary much better when someone directly taught them than when the same person taught on a video (Roseberry et al., 2009). This suggests personal, social language acquisition, not impersonal learning.

According to theory two, then, social impulses, not explicit teaching, lead infants to learn language “as part of the package of being a human social animal” (Hollich et al., 2000). Those same impulses are evident in all the ways infants learn. According to this theory, people differ from the great apes in that they depend on others within their community and thus learn whatever way their culture uses to communicate. Every infant (and no chimpanzee) masters words and grammar to join the social world in which he or she finds himself (Tomasello & Herrmann, 2010).

Cultures vary not only in the languages they speak, but also in how they communicate, some using gestures and touch more than words. A learning theorist might consider the quieter, less verbal child to be developmentally delayed, but this second perspective contends that the crucial aspect of language is social communication, and that the quieter child may simply be communicating in another way. Language is not necessarily spoken.

Theory Three: Infants Teach ThemselvesA third theory holds that language learning is innate; adults need not teach it, nor is it a by-product of social interaction. It arises from the universal human impulse to imitate. As already explained in the research on memory, infants and toddlers observe what they see and apply it—not slavishly, but according to their own concepts and intentions. This may be what they do with the language they hear as well (Saxton, 2010).

The seeds of this perspective were planted soon after Skinner proposed his theory of verbal learning. Noam Chomsky (1968, 1980) and his followers felt that language is too complex to be mastered merely through step-by-step conditioning. Although behaviourists focus on variations among children in vocabulary size, Chomsky focused on similarities in language acquisition—the universals, not the differences.

Noting that all young children master basic grammar at about the same age, Chomsky cited this universal grammar as evidence that humans are born with a mental structure that prepares them to seek some elements of human language—for example, the use of a raised tone at the end of an utterance to indicate a question. Chomsky labelled this hypothesized mental structure the language acquisition device (LAD), which enables children to derive the rules of grammar quickly and effectively from the speech they hear every day, regardless of whether their native language is English, Thai, or Urdu.

Other scholars agree with Chomsky that infants are innately ready to use their minds to understand and speak whatever language is offered. All babies are eager learners, and language may be considered one more aspect of neurological maturation (Wagner & Lakusta, 2009). This idea does not strip languages and cultures of their differences in sounds, grammar, and almost everything else, but the basic idea is that “language is a window on human nature, exposing deep and universal features of our thoughts and feelings” (Pinker, 2007).

The various languages of the world are all logical, coherent, and systematic. Infants are primed to grasp the particular language they are exposed to, making caregiver speech “not a ‘trigger’ but a ‘nutrient’” (Slobin, 2001). There is no need for a trigger, according to theory three, because the developing brain quickly and efficiently connects neurons and dendrites to support whichever language the infant hears.

Research supports this perspective as well. As you remember, newborns are primed to listen to speech (Vouloumanos & Werker, 2007), and all infants babble ma-ma and da-da sounds (not yet referring to mother or father). No reinforcement or teaching is required; all infants need is for dendrites to grow, mouth muscles to strengthen, neurons to connect, and speech to be heard.

All True?Which of these three perspectives is correct? Perhaps all of them. In one monograph that included details and results of 12 experiments, the authors presented a hybrid (which literally means “a new creature, formed by combining other living things”) of previous theories (Hollich et al., 2000).

Since infants learn language to do numerous things—indicate intention, call objects by name, put words together, talk to family members, sing to themselves, express their wishes, remember the past, and much more—some aspects of language learning may be best explained by one theory at one age and other aspects by another theory at another age. Although originally developed to explain acquisition of first words, mostly nouns, this hybrid theory also explains learning verbs: Perceptual, social, and linguistic abilities combine to make that learning possible (Golinkoff & Hirsh-Pasek, 2008).

After intensive study, another group of scientists also endorsed a hybrid theory, concluding that multiple attentional, social and linguistic cues contribute to early language (Tsao et al., 2004). It makes logical and practical sense for nature to provide several paths toward language learning and for various theorists to emphasize one or another of them (Sebastián-Gallés, 2007), and for some children to learn better one way, and others another way (Goodman et al., 2008).

Some scholars, inspired by evolutionary theory, think that language is the crucial trait that makes humans unlike any other species—that “language is entwined with human life” (Pinker, 2007, p. viii). If that is true, then there must be many paths to language learning, to ensure that every human learns.

Adults need to talk often to infants (theory one), encourage social connections (theory two), and appreciate the innate abilities of the child (theory three). As one expert concludes,

The idea that every theory is correct in some way may seem uncritical, naïve, and idealistic. However, a similar conclusion was arrived at by scientists extending and interpreting research on language acquisition. They contend that language learning is neither the direct product of repeated input (behaviourism) nor the result of a specific human neurological capacity (LAD). Instead, different aspects of language may have evolved in different ways, and as a result a piecemeal and empirical approach is needed (Marcus & Rabagliati, 2009). In other words, a single theory that explains how babies learn language does not reflect the data: Humans accomplish this feat in many ways.

Infants are active learners not only of language (as just outlined) and of perceptions and motor skills (as explained in the first half of this chapter), but also of everything else in their experience. Active and interactive social and emotional understandings are described in the next chapter.