Karmiloff, Kyra; Annette Karmiloff-Smith;
Pathways to Language: From Fetus to Adolescent (The Developing Child)
Harvard University Press, 2002, 268 pages [gbook]
ISBN 0674008359, 9780674008359
topics: | language-acquisition | developmental |
An absolutely fascinating page-turner... while dealing with very serious scholastic issues, you cannot fail to be captivated by the sheer power of the infant mind... Delightful research.
When children initially produce grammar, their language often sounds rather
like the abbreviated language of telegrams ("Daddy gone," "Mummy shoe," "See
big car"). This is why, in the past, this type of early output was referred
to as telegraphic speech. At this stage, toddlers omit indefinite and
definite articles, as well as prepositions and the like. They also leave out
morphemes like plural "s," progressive "ing", p.94
Between four and six months, the variety of vocalizations she makes
increases significantly. The infant now produces raspberry noises,
interrupted by vowel-like sounds. This clumsy transition between vowel and
consonant-type utterances is called marginal babbling.
From about seven months onward, vowel-consonant transitions become
smoother. Productions now take the form of repeated syllabic strings such
as “da-da-da-da.” This stage is referred to as canonical babbling, and
toward the end of the first year it becomes quite complex, involving
variegated sequences such as “babi-babi,” “biba-biba.” Research into the
structure of babbling suggests that it is not until about ten months of
age, when speech processing is becoming increasingly specialized, that the
child’s native tongue begins to affect the kinds of sounds the baby
utters.
When do the repeated syllables “ma-ma-ma” become a symbol for “mother”? Is the utterance “ahhr” still merely a babble if the baby is pointing to a car at the same time, or is it the child’s idiosyncratic yet consistent sound for “car” that now has real referential status? Even experienced researchers can, at times, find it difficult to determine the nature of these sounds, because the transition from canonical babbling to first words is neither clear-cut nor abrupt. well before uttering her first word, the infant has been busy segmenting the incoming speech stream... early on in language development the infant discovers the phonotactics of her language and learns which sound combinations are legal and which are not. ... she is also particularly sensitive to stress patterns. Such clues help the infant learn to segment the stream of sounds into separate words. They also assist her in recognizing the presence of the same word when it appears in different linguistic contexts, or when it is pronounced by different speakers, both of which dramatically alter the acoustic signal of individual words. 57 symbols: - arbitrary except onomatopoeic words such as “sizzle,” “crack,” or “moo” - conventional
Research has shown that girls tend to produce language earlier than boys. This turns out to be a biological influence. Extensive investigation into the linguistic environments of infants has revealed that this gender difference is not a result of linguistic experience. Studies of Western cultures show that parents talk as much and in a similar way to baby girls as they do to baby boys. It is thought, therefore, that differences between the sexes must be due to certain physiological factors... In their studies of American families, developmental psycholinguists Letitia Naigles and Erika Hoff-Ginsberg have shown that when children acquire new verbs, for instance, the frequency with which each verb occurs in parental input has the greatest effect on speed of acquisition of that verb. ... verb acquisition is also affected by position... When verbs regularly appear at the end of speech segments, as in questions like, “where’s Daddy going?” they are actually easier for infants to learn than when they appear at the start of sentences or mid-sentence, such as “Daddy’s going to work.” A second factor that contributes to the rate at which a verb is acquired is the diversity of grammatical structures in which the verb appears. So it is beneficial for the toddler to hear the same verb used in a number of different ways: in questions, in commands, in exclamations, or in declarative statements. In each case, the verb will be surrounded by different types of words, and the word order, as well as intonation and stress patterns, will vary. The verb itself will take different forms...
Infants begin producing their first recognizable words between roughly twelve and twenty months. This, however, does not mean that they have no receptive lexicon before they can speak. The child’s receptive lexicon refers to the words she can understand... Using parental diaries, Paula Menyuk and her colleagues found that at around twelve months mothers estimated that their infants understood on average at least ten words. Infants’ language comprehension increased to fifty words by fourteen months, and to over one hundred by eighteen months. As far as the productive lexicon is concerned, by twenty-four months most toddlers can produce some fifty different words. These first words tend to be similar across cultures and languages and include the names of familiar people, objects, animals, food, body functions, and social routines or commands. Word comprehension and production thus progress at separate rates. while girls usually produce words earlier than boys, comprehension rates turn out to be far more equal between the sexes throughout development. the earliest words produced by infants are indeed often houns. Nonetheless, Alison Gopnik has shown that verbs, adverbs, and the like appear early too. Words like “gone” (used by infants to denote that something is finished or someone has disappeared), “bye-bye” (to refer to someone or something about to disappear), “done” or “there” (denoting successful goal achievement), “uh-no” (denoting failure to achieve a goal), and “more” (requesting recurrence of food, a game, or an event) are also very common first words.
Rather than simply identifying first words, what is more revealing is discovering the function these words have for the child. This provides clues as to why some words might develop before others. While infants may copy their caregivers in simply naming things, the very earliest words produced are often termed proto-imperatives because they refer to something that the infant wants. These are not real imperatives in the adult sense (a command like “give me a cookie now”). (“juice”, “bottle”, or “door” to signal that she wants to go out). the child may use the word “dog” to signify “the dog is scratching himself,” “the dog’s leash is hanging on the hook,” or “I want the dog to come in.” It might even be used to point to a past event, that is, a toy that the toddler saw the dog chewing earlier. The importance of both shared experience and shared linguistic context was beautifully illustrated many years ago by Catherine Snow, who documented this conversation between an experimenter and an eighteen-month-old infant while the mother was out of the room. Child: Bandaid. Experimenter: Where’s your bandaid? Child: Bandaid. Experimenter: Do you have a bandaid? Child: Bandaid. Experimenter: Did you fall and hurt yourself? (Mother enters the room.) Child: Bandaid. Mother: Who gave you the bandaid? Child: Nurse. Mother: Where did she put it? Child: Arm. The child and her mother continued for several more turns a conversation composed of extensive conversational exchanges about their shared visit to the doctor. It is important to note that they had not merely shared the experience of making the visit, but above all had previously shared the linguistic experience of discussing the visit together. Unlike the experimenter, the mother therefore knew what kinds of questions would elicit the child’s broader word knowledge. As Jerome Bruner and his collaborators showed, this kind of interaction between mother and child provides a kind of “support system” that serves as a scaffold for early lexical development. undergeneralization: use the word “train” to refer only to his own wooden engine, not to real trains or to cartoon trains on television. overgeneralization: happens somewhat later - e.g. tends to refer to any four-legged animal- cat, dog, horse, sheep-as “doggy.”
Sandra Waxman and her collaborators have shown that the use of words can direct infants’ attention to what is common among objects and thereby encourage them to form new conceptual categories. Waxman tested thirteen-month-old infants with a simple method in order to ascertain whether the presence or absence of a label affects whether or not a new conceptual category is formed. She divided her infants into two groups. One group was presented with a number of interestingly novel objects of varying shapes and colors that could be grouped as belonging to different classes based on these perceptual properties. The researcher then picked up one of the objects and, without labelling, said: “Look at this, look at this, find me another one.” This group of infants was not very successful at forming the new category: they had difficulty in selecting an appropriate “other one.” By contrast, the second group of infants was shown the same novel objects, but this time the experimenter labelled the selected item: “Look at this blick, look a blick, find me another blick.” In this case, the thirteen-month-olds were successful in selecting an object from the same class. Labeling an object signified to the child that a category was involved, because children of this age are sensitive to the fact that nouns refer to categories. Those in the second group were thus more successful in searching for objects from the same class than those in the first group. So there is a dynamic feedback between developing cognitive skills and growing vocabulary, and words can act as an invitation to form a category.
Four main cognitive constraints have been identified that help children narrow down the meaning of words: A. mutual exclusivity if the child already knows the word “car,” he will not think a new word refers to cars. B. fast mapping novel words map onto objects for which the child does not already have a name. [overlaps with mutual exclusion] A mother says “Look! That’s a CUSHION” when her child is looking at a chair with a cushion on it. If the toddler already knows the English word “chair,” she will automatically map the new English word “cushion” onto the unknown object, rather than onto the chair. It is only after their use of language is well established that children accept that one object might have two or more names. This is when they accept that the three words “animal:’ “dog,” and “poodle” might refer to one and the same referent. C. whole object constraint a novel word heard in the presence of a novel object refers to the whole object rather than to its component parts or to its features such as color, shape, or texture. [Once knows the whole, will learn names for parts] Interestingly, color is usually the last attribute to be considered as the possible meaning of a new word, because it is far less informative about the function of an object. D. taxonomic constraint. if a child is taught the new word “bus” and is asked to find another bus, she will choose an object from the vehicle category (truck, car, train) if there is no other bus, rather than something with the same color or texture... The mutual exclusivity and the whole object constraints are commonly used by children as young as three years when identifying the referent of a new word.
Developmental psychologists disagree about whether all the lexical principles are available simultaneously to children at this young age, or whether each one becomes operational at different ages. For instance, one psycholinguist, Ellen Markman, has argued that the constraints are all available at the same developmental time, but that they are selected probabilistically according to the different contexts in which new words are learned. She believes that it is the context of word learning rather than the age of the child that will call for one or several constraints to operate. By contrast, other researchers, such as Roberta Golinkoff and Kathy Hirsh-Pasek, claim that the lexical principles become operative at different stages in development, with the taxonomic constraint being the last to be displayed in normal development.
Very early in life, infants pay attention to where adults are looking and pointing. A parent will say: “Look at the dog” and will point and look back and forth between the child and the animal to direct the child’s focus of attention toward the correct target. Establishing joint attention and gaze alternation in this way is a partial but vital clue to conveying meaning in such interactions. Interestingly, toddlers make sure that they know where their parent is looking, even while they themselves are engaged in another activity. In one study, it was found that if parents named an object while the child was focused on another, the child would look up, establish where the adult was looking, and map the new word just heard onto the adult’s focus of attention (the target object), rather than onto the object she was focused on. This shows how important social clues may be in helping to establish word meaning.
Take the example of the nonce term “gorp.” The presence of an article “that’s a gorp” tells us that “gorp” is a common noun. But if no article were present (for example, “that’s Gorp”), we would guess that it was a proper name or that it refers to a substance, depending on the referent. Similarly, in “he’s going to gorp,” the word “to” indicates that gorp is a verb. One of the very first experiments on infant understanding of function words was carried out by John MacNamara over twenty years ago. He showed that toddlers as young as seventeen months are sensitive to distinctions between common nouns and proper names. MacNamara invented a series of nonce words (zav, mef, roz, kiv, pex, jop, wug, zon, tiv, vit, neg, cak) to test this. Infants were shown a doll and told, “that’s Zav.” In this case, it was hypothesized that if they were sensitive to the grammatical distinction between the presence and absence of an article, then they should take Zav as the doll’s proper name and only pick up that particular doll when the experimenter asked for “Zav.” Conversely, when they heard “That’s a zav” and were asked for “a zav,” they should hand any one of the group of dolls to the experimenter. This is precisely what happened. Interestingly, the infants did not pay attention to the presence and absence of an article when the same procedure was used to refer to blocks. This suggests that they also know that people or dolls have names, but blocks do not. Daniel Slobin has hypothesized that children use an operating principle that stipulates, “Pay attention to the end of words.” He suggests that this is one of the major constraints on early word learning. As we mentioned earlier, the marker “er” gives clues to the fact that referents like “singer” are animate agents. The presence of the sound “ed” on the ends of verbs points to past tense. Similarly, the marker “s” on dogs, tables, and glasses signals pluralization. Fascinating research using nonce verbs and nouns (for example, “to gorp” or “a wug”), has demonstrated that children as young as three employ such grammatical clues to guess the meaning of words they have never heard before. In sum, one good strategy for distinguishing words and word classes is to pay attention to the ends of words, as Slobin suggests. Slobin (1973) : 'pay attention to the end of word' principle for child language.
Eve Clark: principle of contrast- speakers and listeners take every difference in form (for example, “run” versus “runs”) to signal a difference in meaning. And it may also be a way that parents help their children understand distinctions in meaning. For instance, parents sometimes use words with opposite meanings in the same sentence to make the utterance clearer to their young children. So they may say, “That’s not a BIG truck, it’s a SMALL truck or “The boy’s not RUNNING, he’s WALKING.” Such contrasts may make meaning more transparent and help children store information that goes beyond one particular word to include close synonyms and opposite meanings. Sensitivity to contrast may also help children discover that such pairs of words as “big” and “small” or “running” and “walking” belong to the same word class. Susan Carey invented a clever experiment using overtly contrasting terms to show how quickly children around three years of age can learn a new word. she gave children instructions like “Don’t take the red tray, take the chromium tray.” Here the familiar word “red” provides a useful contrast to the unfamiliar word “chromium” and highlights the linguistic category of the new word (color adjective). Thus the child can use the principle of contrast as a shortcut to the correct meaning of “chromium.” This type of research has shown that young children can learn new words very rapidly, even on a single presentation. In normal daily language experience, we can see that the young child has the benefit of a wide range of helpful, contrastive linguistic clues. These clues help her pinpoint the meaning of new words and work out the relationships between them.
In a study of nearly two thousand American children, Larry Fenson and his colleagues charted the progress in word learning by infants and toddlers between eight and thirty months. They found that children produced an average of ten words at thirteen months. But of course, as we have stressed, there is considerable individual variation, with some children producing ten words at eight months and others almost none until sixteen months. The fifty-word level was reached, on average, around seventeen months (with a range of ten to twenty-four months), and by twenty-four months the toddlers produced between forty and six hundred or more words. At all of these ages, infants were found to understand significantly more words than they could produce, with most thirteen-month-olds understanding just over one hundred words and seventeen-montholds understanding on average 180 words. By around thirty to thirty-six months, most toddlers in the study had acquired roughly 150 words in their productive lexicon. When the child’s vocabulary reaches the 150-word level, for most (but not all) children there is a sudden increase in the rate at which new words are learned. For some children, the spurt occurs earlier when they are producing only 70-100 words, whereas for others it happens when they can say about 200 words. Prior to the vocabulary spurt, children learn on average about three words per week. But when they enter the vocabulary spurt stage, their learning of new words increases dramatically to about eight to ten words per day. Researchers have differed in their interpretation of this sudden explosion in labeling. Some have argued that the child experiences a “naming insight”-a sudden realization that every object and action has a name. Others have suggested that the spurt is due to a conceptual change in the child’s overall cognitive development. This has been linked to the fact that it is usually when children can exhaustively sort objects into categories that their vocabularies start to increase exponentially.
Today, however, it is more generally accepted that the vocabulary spurt is simply a function of the child’s current state of learning-that is, the number of words already learned. In sum, development does not proceed by equal increments, but is nonlinear. Note that individual differences can be more readily accounted for by dint of this explanation. It is not therefore claimed that children undergo the vocabulary spurt at any particular age. Rather, they do so at the point at which their vocabulary reaches a certain size. Virginia Marchman and Elizabeth Bates have called this the critical mass hypothesis. This stage of vocabulary development also coincides with the point at which grammar takes off... Interestingly, even children who are developmentally delayed and who start producing words much later than typically developing children usually also start to combine words grammatically once their productive vocabularies have reached at least 150-200 words.
Lorraine Tyler and her collaborators have shown that from as young as five years of age, and perhaps before, children store words in memory much like adults do, with semantic relations being more important (that is, causing faster reaction times) than thematically and phonologically related cues. One of the most extensive developmental studies on the concept “word was carried out by Ioanna Berthoud-Papandropoulou, a developmental psycholinguist from the Piagetian school of thought in Geneva. In a series of experiments, she endeavored to find out what counts as a word for children. So, for instance, she asked the following type of questions: Is “table” a word? Is “silence” a word? Is “when” a word? Is “the” a word? In response to these questions, Berthoud-Papandropoulou found that five-year-olds think that only concrete nouns referring to objects are words. Although by about age seven children accept that abstract nouns are words, it is not until as late as ten years that they consistently accept articles like “a” as “real” words. Berthoud-Papandropoulou, Ioanna; An experimental study of children's ideas about language In The child's conception of language, p.55-64. (Springer, 1978). --- The following dialogue between a mother and her four-year-old daughter illustrates beautifully children’s metalinguistic curiosity. From a very young age, children are clearly interested in how words work and not simply in what they refer to. Yara (four years old): What’s that? Mother: It’s a typewriter. Yara (frowning): No, you’re the typewriter, that’s a typewrite. Recently the four-year-old son of Yara, now thirty-two, was cooking with his mother and got very angry: Alexander: I’m not the cook, I’m the cooker, Mummy. I’m the cooker today. [Mother explained that the stove was the cooker.] Alexander (furious): No, no, no, that’s the cook, it’s me the cooker.