In a longitudinal investigation of 40 child–mother dyads, we examined prediction from three indexes of children's own language: (1) vocal imitations, (2) first spontaneous words in production, and (3) receptive language starting at 0;9, and their mothers' verbal responsiveness at 0;9 and 1;1, to the developmental onset of three significant language milestones of the second year: (1) 50 words in productive language, (2) combinatorial speech, and (3) the use of language to express a memory. In these analyses, we utilized EVENTS HISTORY ANALYSIS, a statistical technique well suited to questions concerning when in development certain events begin and the extent to which predictors influence the timing of those events. The timing of children's first words in production, the timing of their achievement of 50 words in receptive language, and maternal responsiveness at 1;1 each contributed uniquely to variation in the timing of the three language milestones. When child and mother factors were considered together, the onset of the three language milestones differed by as much as 0;5 months for children in the lower and upper 10th percentiles of the predictor variables. The present findings contribute to generating and testing specific models about child and mother factors thought to explain variation in key aspects of children's second-year language development.

The purpose of the present study was to determine whether the VERBAL component of babytalk affected the vocal quality of infants. Two groups of 20 0;3 infants experienced either conversational turn taking or random responsiveness of an adult. Adult responsiveness consisted of a smile, light touch to the abdomen, and a NONVERBAL ‘tsk, tsk, tsk’ sound (instead of speech). All infant vocalizations were counted and then coded as ‘syllabic’ or ‘vocalic’ sounds. The results of the study demonstrated that TURN TAKING facilitated a speak-listen pattern of vocalizing by the infant, but in the absence of the VERBAL component of the adult's response, turn taking had no special facilitative effect on syllabic sounds. It was concluded that what adults say to 3-month-old infants influences what infants ‘say’ in return. Possible mechanisms underlying the infant's vocal response to verbal input were reviewed. It was suggested that the more mature sounds (syllabic) may proportionally increase as a result of the combined effects of turn-taking and verbal stimulation on the motor control of respiration and phonation.

Phonological representation for adult speakers is generally assumed to include sub-lexical information at the level of the phoneme. Some have suggested, however, that young children operate with more holistic lexical representations. If young children use whole-word representation and adults employ phonemic representation, then a component of phonological development includes a transition from holistic to segmental storage of phonological information. The present study addresses the nature of this transition by investigating the prevalence and patterns of intra-word production variability during the first year of lexical acquisition (1;0–2;0). Longitudinal data from four typically developing children were analysed to determine variability at each age. Patterns of variability are discussed in relation to chronological age and productive vocabulary size. Results show high overall rates of variability, as well as a peak in variability corresponding to the onset of combinatorial speech, suggesting that phonological reorganization may commence somewhat later than previously thought.

Through an analysis of chimpanzee–human discourse, we show that two Pan troglodytes chimpanzees and two Pan paniscus chimpanzees (bonobos) exposed to a humanly devised symbol system use partial or complete repetition of others' symbols, as children do: they do not produce rote imitations, but instead use repetition to fulfil a variety of pragmatic functions in discourse. These functions include agreement, request, promise, excitement, and selection from alternatives. In so doing, the chimpanzees demonstrate contingent turn-taking and the use of simple devices for lexical cohesion. In short, they demonstrate conversational competence. Because of the presence of this conversational competence in three sibling species, chimpanzees, bonobos, and humans, it is concluded that the potential to express pragmatic functions through repetition was part of the evolutionary history of human language, present in our common ancestor before the phylogenetic divergence of hominids and chimpanzees. In the context of these similarities, two interesting differences appeared: (1) Human children sometimes used repetition to stimulate more talk in their conversational partner; the chimpanzees, in contrast, use repetition exclusively to forward the non-verbal action. This difference may illuminate a unique feature of human linguistic communication, or it may simply reflect a modality difference (visual symbols used by the chimpanzees, speech used by the children) in the symbol systems considered in this research. A second difference seems likely to reflect a true species difference: utterance length. The one- and two-symbol repetitions used by the chimpanzees to fulfil a variety of pragmatic functions were less than half the maximum length found in either the visual symbol combinations addressed to them by their adult human caregivers or the oral repetitions of two-year-old children. This species difference probably reflects the evolution of increased brain size and consequent increased memory capacity that has occurred since the phylogenetic divergence of hominids and chimpanzees four to seven million years ago.

Some studies have shown that children tend to interpret figurative language literally. Our hypothesis is that they can reach an idiomatic competence if idioms are presented within a rich informational environment allowing children to grasp their figurative sense. First and third graders were presented with narratives biased both to the figurative meaning of idioms (experiment 1) and to the literal meaning (experiment 2) and then given a comprehension task. Experiment 3 was designed to investigate children's production of idioms as compared to the comprehension abilities explored in experiments 1 and 2. Results show that informative contexts can improve children's ability to perceive idiomatic meanings even at the age of seven; and that children are less able to produce idioms than to comprehend them. Generally results emphasize that children seem able to perceive that language can be both figurative and literal.

Hirsh-Pasek, Treiman & Schneiderman (1984).and Demetras, Post & Snow (1986).have recently suggested that certain types of parental repetitions and clarification questions may provide children with subtle cues to their grammatical errors. We further investigated this possibility by examining parental responses to inflectional over-regularizations and wh-question auxiliary-verb omission errors in the sets of transcripts from Adam, Eve and Sarah (Brown 1973). These errors were chosen because they are exemplars of overgeneralization, the type of mistake for which negative information is, in theory, most critically needed. Expansions and Clarification Questions occurred more often following ill-formed utterances in Adam's and Eve's input, but not in Sarah's. However, these corrective responses formed only a small proportion of all adult responses following Adam's and Eve's grammatical errors. Moreover, corrective responses appear to drop out of children's input while they continue to make overgeneralization errors. Whereas negative feedback may occasionally be available, in the light of these findings the contention that language input generally incorporates negative information appears to be unfounded.

Despite growing empirical evidence to the contrary, claims continue to be made that the grammar of people with Williams syndrome (WS) is intact. We show that even in a simple elicited imitation task examining the syntax of relative clauses, older children and adults with WS (n = 14, mean age = 17;0 years) only reach the level of typical five-year-old controls. When tested systematically in a number of different laboratories, all aspects of WS language show delay and/or deviance throughout development. We conclude that the grammatical abilities of people with WS should be described in terms of relative rather than absolute proficiency, and that the syndrome should no longer be used to bolster claims about the existence of independently functioning, innately specified modules in the human brain.

Various kinds of children's lexical errors, mostly based on similarity in sound, are presented and classified. At the earliest stage some children are found to pursue a HOMONYM STRATEGY, actively seeking to combine adult word-patterns to limit their output repertoire. The associations between words underlying these productive homonyms, together with perception-based errors, blends, and other word-substitutions, are compared with malapropisms from a slightly older group of children as well as with data from adults. Analysis of these data makes it possible to chart developmental changes in the phonological links which form one substructure of the lexicon.

Experiments 1 and 2 examined the effects of infant-directed (ID) speech on adults' ability to learn an individual target word in sentences in an unfamiliar, non-Western language (Chinese). English-speaking adults heard pairs of sentences read by a female, native Chinese speaker in either ID or adult-directed (AD) speech. The pairs of sentences described slides of 10 common objects. The Chinese name for the object (the target word) was placed in an utterance-final position in experiment? (n= 61) and in a medial position in experiment 2 (n= 79). At test, each Chinese target word was presented in isolation in AD speech in a recognition task. Only subjects who heard ID speech with the target word in utterance-final position demonstrated learning of the target words. The results support assertions that ID speech, which tends to put target words in sentence-final position, may assist infants in segmenting and remembering portions of the linguistic stream. In experiment 3 (n= 23), subjects judged whether each of the ID and AD speech samples prepared for experiments ? and 2 were directed to an adult or to an infant. Judgements were above chance for two types of sentence: ID speech with the target word in the final position and AD speech with the target word in a medial position. In addition to indirectly confirming the results of experiments 1 and 2, these findings suggest that at least some of the prosodic features which comprise ID speech in Chinese and English must overlap.

Bilingual acquisition can shed light on the cues children use in acquiring language. The purpose of this paper was to examine whether frequency, ambiguity or language dominance could explain crosslinguistic transfer in compound nouns. Crosslinguistic transfer would appear in the form of compound reversals. 25 monolingual English children between the ages of three and four years and 25 age-matched French-English bilingual children were asked to create and indicate their understanding of novel compound nouns. In production, the bilingual children reversed compounds in English more often than the monolingual children but equally often in French and English. In comprehension, there were no differences between groups. These results cannot be explained by any previous explanation of transfer. Implications for the theory of language acquisition are discussed.

The structure of contingent query sequences within adult–child discourse was examined. The children, aged 1; 11–3; 0 in language stages I–III, demonstrated basic knowledge of the contingent query. Implications for conceptualizations of the young child's communicative competence and for theoretical formulations of the query sequence itself are discussed.

This study set out to explore the contexts in which preschool children use private speech, or self-talk, in the naturalistic setting of the preschool classroom, and age-related changes in the contexts in which preschoolers talk to themselves. A total of 2752 naturalistic observations of fourteen three-year-old and fourteen four-year-old children were conducted using a time-sampling procedure in two preschool classrooms over the course of one semester. Results from logistic regression analyses revealed that both age groups were (a) more likely to use private speech during the self-selected activity classroom context as opposed to both large group and outside free play classroom contexts, and (b) most likely to talk to themselves when alone, next likely in the presence of peers, and least likely when in the presence of a teacher. Although the probability of private speech among three-year-old children did not vary as a function of the child's immediate activity, four-year-old children's private speech was more likely to occur during sustained and focused goal-directed activity as opposed to rapidly-changing and non goal-directed activity. The findings suggest that private speech appears systematically in young children and that, in several ways, four-year-old children use private speech more selectively than three-year-olds.

Passive structures are typically assumed to be one of the later acquired constructions in child language. English-speaking children have been shown to produce and comprehend their first simple passive structures productively by about age four and to master more complex structures by about age nine. Recent crosslinguistic data have shown that this pattern may not hold across languages of varying structures. This paper presents data from four Inuit children aged 2;0 to 3;6 that shows relatively early acquisition of both simple and complex forms of the passive. Within this age range children are productively producing truncated, full, action and experiential passives. Some possible reasons for this precociousness are explored including adult input and language structure.

Much of adult communication is carried on at the subtle level of indirect utterance meaning, where the speaker's intent is not literally expressed in his or her utterance. This work investigates the young child's ability to respond appropriately to the intended, as opposed to the literal, meaning of one class of such utterances, requests for action. The data were the responses of five children between 1; 7 and 2; 4 to the direct and indirect requests for action their mothers produced during a natural play session. All the children responded with action to requests for it regardless of how subtly the requests were expressed. The apparent ability of two-year-olds to deal with indirect speech acts is surprising in that the understanding of such utterances by adults is presumed to depend on a combination of sophisticated rule systems. Rather than grant the young child such knowledge, the alternative of an action-based response heuristic is proposed.

The language of mothers and fathers to their toddler sons and daughters at play with three different types of toy was analysed for both sentence types and structural elements. Two of the play contexts, dolls and vehicles, were highly sex-role stereotyped, and the third, shape sorters, was neutral. Few differences in speech were found as a function of either parent or child gender. Each of the three play contexts, however, elicited its own language pattern. With dolls, parental speech was characterized by a relatively large amount of language and a frequent use of questions and nouns, especially by contrast with vehicle play, which involved little language. Play with shape sorters elicited a high proportion of directives and attentionals and a relatively low variety in language. These results suggest that children who play frequently with dolls may receive more opportunities to learn and practise language than do children who select other toys for play. In this way early toy preferences may contribute to differential socialization by parents.

In a number of studies, the acquisition of restrictive relative clauses (RCs) shows contrasting findings regarding comprehension and production, with the former usually delayed up to the age of five. As previously claimed in the literature, we suggest that this delay is a task artifact and we present a new procedure for the assessment of restrictive RCs. Data from three- to seven-year-old Italian children were collected and results show that children understand object RCs with preverbal subject in an adult-like manner at four years of age, but some of the three-year-old children were already above chance. Subject relatives show at ceiling performance from three years of age. We consider our results as evidence of continuity between early and adult competence grammars. Children's non-target responses are interpreted as grammatical options exploited by an immature performance system.

This paper focuses on aspects of early lexical acquisition in German. There have been conflicting results in the literature concerning both the pattern of vocabulary growth and the composition of the early lexicon. Our study describes the development of various categories of words and questions the preponderance of nouns in spontaneous speech. 32 children were studied longitudinally through recordings made at age 1;1, 1;3, 1;9 and 3;0. The following properties of the data were investigated: vocabulary size in relation to age, frequency of word use, and distribution of word categories. The results show that use of both types and tokens increases with time. A trend analysis indicates an exponential increase in vocabulary production in the second year, followed by a further expansion. This vocabulary spurt-like pattern can be observed in the use of word types and tokens. The findings in regard to vocabulary composition illustrate the dynamics present in the development of word categories. In the beginning, children use mostly relational words, personal-social words and some onomatopoeic terms. These categories are gradually complemented with nouns, verbs, function words and other words so that we see a balanced lexicon by 3;0. Trend analyses clarify characteristic developmental patterns in regard to certain word categories. Our spontaneous speech data does not support a strong noun-bias hypothesis.

This study evaluates the effects of Age of Exposure to English (AoEE) and Current Input/Output on language performance in a cross-sectional sample of Spanish–English bilingual children. First- (N = 586) and third-graders (N = 298) who spanned a wide range of bilingual language experience participated. Parents and teachers provided information about English and Spanish language use. Short tests of semantic and morphosyntactic development in Spanish and English were used to quantify children's knowledge of each language. There were significant interactions between AoEE and Current Input/Output for children at third grade in English and in both grades for Spanish. In English, the relationship between AoEE and language scores were linear for first- and third-graders. In Spanish a nonlinear relationship was observed. We discuss how much of the variance was accounted for by AoEE and Current Input/Output.

A cross-sectional and a longitudinal study of 2-year-old children was performed to investigate the developmental relationship between understanding differences in spatial point of view and correct comprehension and production of I/you pronouns. In Study I only those children who demonstrated understanding that individuals' points of view can differ had begun to master speaker's point of view, as shown by correct use of some of the pronouns. Only children with complete understanding of points of view were able to use all I/you pronouns without errors. In Study 11 no child used the set of I/you pronouns without errors until s/he had complete understanding of points of view. Across children, a given pronoun tended not to be free of errors until the child understood that points of view can differ. Results are interpreted to support the hypothesis that understanding spatial points of view is a cognitive prerequisite to understanding speaker's point of view, which governs the pragmatics of 11 you pronouns.

When children reduce onset clusters to singletons, a common pattern is for the least sonorous member of the adult cluster to be produced. Within OPTIMALITY THEORY (Prince & Smolensky, 1993), this pattern has been accounted for in terms of a fixed ranking of onset constraints that evaluate a segment's degree of sonority, whereby onset glides violate the highest ranked constraint, and onset stops the lowest. Not all children follow the sonority pattern, however. In this paper, we apply two fundamental principles of optimality theory to yield predictions about other children's cluster reduction patterns. The first principle is that of FACTORIAL TYPOLOGY, according to which all rankings of constraints should yield possible languages. To produce the sonority pattern, all conflicting constraints must rank beneath the onset sonority constraints. If they rank above the onset sonority constraints, these other constraints will force deviations from the sonority pattern. In this paper, we show how divergences from the sonority pattern are caused by three well-motivated conflicting constraints: *FRICATIVE, *DORSAL, and MAX-LABIAL. This is documented in the speech of two normally developing children (about 1;6–2;3) and a child with a phonological delay (3;8). The second principle we appeal to is that of EMERGENT CONSTRAINT ACTIVITY, according to which the effects of violated constraints can be observed when higher ranked conflicting constraints are not at issue. We show that even when the onset sonority constraints are outranked by the conflicting constraints, under the right circumstances the sonority pattern does emerge in the forms produced by these children.