There is considerable debate about whether early vocalizations mimic the target language and whether prosody signals emergent intentional communication. A longitudinal corpus of four Catalan-babbling infants was analyzed to investigate whether children use different prosodic patterns to distinguish communicative from investigative vocalizations and to express intentionality. A total of 2,701 vocalizations from 0;7 to 0;11 were coded acoustically (by marking pitch range and duration), gesturally, and pragmatically (by marking communicative status and specific pragmatic function). The results showed that communicative vocalizations were shorter and had a wider pitch range than investigative vocalizations and that these patterns in communicative vocalizations depended on the intention of the vocalizations: requests and expressions of discontent displayed wider pitch range and longer duration than responses or statements. These results support the hypothesis that babbling children can successfully use a set of prosodic patterns to signal intentional speech.

Overgeneralization occurs when a child uses the wrong word to name an object and is often observed in the early stages of word learning. We develop a method to elicit overgeneralizations in the laboratory by priming children to say the names of objects perceptually similar to known and unknown target objects. Experiment 1 examined 18 two-year-old children's labelling of familiar and unfamiliar objects, using a name that was previously produced. Experiment 2 compared the labelling of 30 two-year-olds and 39 four-year-olds when presented with completely novel objects. The findings suggest that the retrieved word is a blend of previous activation from the prior retrieval and activation engendered by the similarity of the test object to instances of the target category. We put forward a theoretical account of overgeneralization based on current models of adult language processing. The account suggests a common mechanism of activation and retrieval, which may explain not only momentary lapses in the correct selection of words, but other types of naming errors traditionally thought to reflect differences in children's underlying category representations or, perhaps, gaps in their knowledge of words.

To explore adjective language development and to examine its relationship to seriation, several tasks were given to 40 children aged 4;0 to 8;0. Comprehension and production of various adjective forms were measured: vocabulary, coordination, comparison. The ability to order objects by size was used to assess intuitive-level seriation. In addition to yielding information about children's meanings and use of adjective forms, results indicated that vocabulary and comprehension were more important than language production for distinguishing senators from non-senators. The relevance of findings for Sinclair de Zwart's observations and for the Clarks' hypotheses about adjective development is discussed.

Fourth-, eighth-, twelfth-graders and expert adults each wrote persuasive messages to three audiences arrayed along a dimension of intimacy to writer. Measures of social cognitive ability were also obtained. Scripts were analysed for (1) fluency, (2) subordination, (3) clause length, (4) logical adverbial clauses, and (5) conjunctions of conclusion. In addition to general developmental trends, results indicated effects of audience adaptation and of mediation of social cognitive ability. Findings support the view that evidence of later language development must be interpreted in light of communicative demands of tasks and subjects' rhetorical skills.

This study examined the production of three types of noun plural inflections, feminine sound plural (FSP), masculine sound plural (MSP), and broken plural (BP) in Kuwaiti Arabic-speaking children with and without language impairment. A total of thirty-six Kuwaiti participants – twelve adults, twelve children with specific language impairment (SLI), and twelve typically developing age-matched controls (TD) were presented with twenty-seven pictured stimuli of real and nonsense words. The results showed that the TD children were significantly more accurate in using the required noun plural inflections than the SLI group. The TD children's preferred overgeneralization strategy was to substitute FSP for the regular MSP and irregular BP contexts much more than their peers with SLI. The performance of the SLI group also differed from that of their age-matched counterparts in the number of errors and their distribution across categories. The results are discussed in the light of relevant theories of atypical language development.

Developmental differences in object word learning and use were investigated. Two groups of infant speakers: Beginner (vocabularies under 50 words) and Advanced (vocabularies over 50 words), participated in a concept formation and word learning and generalization experiment. Results indicated that both speaker groups formed concepts of and learned words for the to-be-learned objects, and generalized these words. However, Advanced speakers learned more concepts and words, and engaged in broader generalization than Beginner speakers. The following variables did not account for these developmental differences: child age, object permanence development, maternal speech, child action on objects. These findings can be explained by developmental differences in both the number and kind of object concepts formed in the second year. Words were primarily acquired for object concepts by both speaker groups. However, Beginner speakers formed fewer concepts, thus having a less extensive conceptual base supporting word learning. This may account for their lower levels of vocabulary acquisition. Additionally, Beginner speakers appear to form prototype/exemplar-based object concepts, leading to limited word extension, while Advanced speakers form featurally based object concepts, leading to broader extension.

This study examined the distribution of two Hebrew nominal structures – N–N compounds and denominal adjectives – in spoken and written texts of two genres produced by 90 native-speaking participants in three age groups: eleven/twelve-year-olds (6th graders), sixteen/seventeen-year-olds (11th graders), and adults. The two constructions are later linguistic acquisitions, part of the profound lexical and syntactic changes that occur in language development during the school years. They are investigated in the context of learning how modality (speech vs. writing) and genre (biographical vs. expository texts) affect the production of continuous discourse.

Participants were asked to speak and write about two topics, one biographical, describing the life of a public figure or of a friend; and another, expository, discussing one of ten topics such as the cinema, cats, or higher academic studies. N–N compounding was found to be the main device of complex subcategorization in Hebrew discourse, unrelated to genre. Denominal adjectives are a secondary subcategorizing device emerging only during the late teen years, a linguistic resource untapped until very late, more restricted to specific text types than N–N compounding, and characteristic of expository writing. Written texts were found to be denser than spoken texts lexically and syntactically as measured by number of novel N–N compounds and denominal adjectives per clause, and in older age groups this difference was found to be more pronounced. The paper contributes to our understanding of how the syntax/lexicon interface changes with age, modality and genre in the context of later language acquisition.

In this paper we investigate the development of interactive communication skills in 170 children aged seven to thirteen. Using a communication task that allows extended dialogues between pairs of young speakers, we are able to assess both the overall communicative success achieved by any pair; and from an analysis of the dialogues we can identify several interactive strategies that characterize older and more successful communicators. Successful communication involves the active involvement of both participants: asking and answering questions, volunteering information and responding sensitively to contributions from their partners. In contrast to the process of language acquisition, the development of these interactive skills takes place over an extended time period and subjects vary greatly in their ability to communicate effectively. For many analyses differences in the communicative success achieved by subjects differ more within than between age groups. For example, a substantial minority of our oldest subjects communicate no better than children six years younger

Scholars have addressed a range of questions about language development, but for some reason have neglected to ask why infants begin to talk. Biologists often prefer ‘how’ to ‘why’ questions, but it is possible to ask about the immediate consequences of developing behaviours – an acceptable strategy for attacking causation – and psycholinguists can study the immediate consequences to the infant of behaviours that lead to linguistic competence. This process is demonstrated with a series of illustrative proposals as to the short- and long-term consequences of vocal learning and utterance storage, two developmental phases that lead to talking, as well as the act of talking itself. The goal is to encourage investigation of behavioural dispositions that nudge the child, by degrees, towards proficiency in the use of spoken language.

The study investigates how basic communicative functions expressed by utterance modalities (declarative, exclamative, injunctive, interrogative) emerged in the early language of a French child, and examines whether and how morphosyntactic and prosodic devices were used to mark these contrasts. A longitudinal corpus of naturalistic productions was collected between the ages of 1;2 and 1;9, and 960 utterances were subjected to functional, prosodic and grammatical analyses. Declarative, exclamative and injunctive utterances were found from 1;2, and first interrogatives appeared at 1;6. Intonation contours varied as a function of utterance modality and were largely in accordance with the patterns in French: declaratives and exclamatives were falling, interrogatives rising and injunctives split between falling and rising contours depending on their specific functions. A quarter of the productions involved an elementary grammatical marking of utterance modality such as interjections, imperative or indicative verbal forms, or interrogative morphemes. These findings indicate an early and complementary use of prosodic and grammatical devices in the child's construction of the linguistic system.

This study assesses the role of frequency of input in the acquisition of the present perfect by Scottish and American children. Two questions were addressed: (1) Do adults speaking Scottish English use the present perfect more frequently in speech to children than those speaking American English? (2) If there is a difference in the frequency of input, how does this affect the course of development of this structure in the language of Scottish vs. American children? Cross-sectional data were collected from 12 Scottish and 12 American children aged 3; 0 to 6; 4 and from adults interacting with them in naturalistic settings. The data led to the conclusions that (1) Scottish adults use the present perfect construction in their speech to children much more frequently than American adults do; (2) Scottish children use the present perfect construction in their speech long before their American counterparts; and (3) frequency of input does play a major role in the timing and order of acquisition of the present perfect. However, its role appears to be an interactive one, in which it conspires with factors such as semantic, syntactic, and cognitive simplicity to make some forms easier to learn than others.

This study examined the linguistic and individual-level factors that render case marking a vulnerable domain in English-dominant Greek heritage children. We also investigated whether heritage language (HL) children can use case-marking cues to interpret (non-)canonical sentences in Greek similarly to their monolingual peers. A group of six- to twelve-year-old Greek heritage children in New York City and a control group of age-matched monolingual children living in Greece participated in a production and a picture verification task targeting case marking and (non-)canonical word order in Greek. HL children produced syncretic inflectional errors, also found in preschool monolingual children. In the comprehension task, HL children showed variable performance on the non-canonical OVS but ceiling performance on the SVO conditions, which suggests influence from English. Linguistic factors such as case transparency affected comprehension, whereas child-level factors such as proficiency and degree of (early) use of Greek influenced performance on both modalities.

An experiment is described which investigates preschool children's understanding of temporal terms. Children aged 2;11 to 4;5 were required to act out situations described by sentences containing before and after. One set of sentences used both a simplified task and simplified materials. These sentences were simple commands, and they only required the children to act out the situation described by the main clause in order to demonstrate comprehension. Performance with these sentences was superior to performance with sentences like those of Clark (1971) and Grain (1982). In addition, children only used an order-of-mention strategy with the Clark sentences. With both the Clark and the Grain sentences, there were more omissions of the subordinate clause in before sentences than in after sentences. There was also a tendency, with these two types of sentence, for children to act out only the first clause in before sentences.

This study examined the quantity and quality of parental linguistic input to toddlers with moderate hearing loss (MHL) compared with toddlers with normal hearing (NH). The linguistic input to eighteen toddlers with MHL and twenty-four toddlers with NH was examined during a 10-minute free-play activity in their home environment. Results showed that toddlers with MHL were exposed to an equivalent amount of parental linguistic input compared to toddlers with NH. However, parents of toddlers with MHL used less high-level facilitative language techniques, used less mental state language, and used shorter utterances than parents of toddlers with NH. Quantity and quality measures of parental linguistic input were positively related to the expressive language abilities of toddlers with MHL.

This study investigates subject omission in six English-Inuktitut simultaneous bilingual children, aged 1;8–3;9, to examine whether there are cross-language influences in their language development. Previous research with other language pairs has shown that the morphosyntax of one language can influence the development of morphosyntax in the other language. Most of this research has focused on Romance-Germanic language combinations using case studies. In this study, we examined a language pair (English-Inuktitut) with radically different morphosyntactic structures. Analysis of the English-only and Inuktitut-only utterances of the children revealed monolingual-like acquisition patterns and subject omission rates. The data indicate that these bilingual children possessed knowledge of the target languages that was language-specific and that previously identified triggers for crosslinguistic influence do not operate universally.

Infant-directed speech (IDS) is a specific register that adults use to address infants, and it is characterised by prosodic exaggeration and lexical and syntactic simplification. Several authors have underlined that this simplified speech becomes more complex according to the infant's age. However, there is a lack of studies on lexical and syntactic modifications in Italian IDS during the first year of an infant's life. In the present study, 80 mother–infant dyads were longitudinally observed at 3, 6, 9, and 12 months during free-play interactions. Maternal vocal productions were subsequently coded. The results show an overall low lexical variability and syntactic complexity that identify speech to infants as a simplified register; however, the high occurrence of complex items and well-structured utterances suggests that IDS is not simple speech. Moreover, maternal IDS becomes more complex over time, but not linearly, with a maximum simplification in the second half of the first year.

In the current debate about the abstractness of children's early grammatical knowledge, Tomasello & Abbott-Smith (2002) have suggested that children might first develop ‘weak’ or ‘partial’ representations of abstract syntactic structures. This paper attempts to characterize these structures by comparing the development of constructions around verbs in Tomasello's (1992) case study of Travis, with those of 10 children (Stage I–II) in a year-length, longitudinal study. The results show some evidence that children's early knowledge of argument structure is verb-specific, but also some evidence that children can generalize knowledge about argument structure across verbs. One way to explain these findings is to argue that children are learning limited scope formulae around high frequency subjects and objects, which serve as building blocks for more abstract structures such as S+V and V+O. The implication is that children may have some verb-general knowledge of the transitive construction as early as Stage I, but that this knowledge is still far from being fully abstract knowledge.

Why are young children's utterances short? This elicited imitation study used a new task – double imitation – to investigate the factors that contribute to children's failure to lexicalize sentence subjects. Two-year-olds heard a triad of sentences singly and attempted to imitate each; they then again heard the same triad singly and again attempted to imitate each. Comparisons between the two attempts showed that children's second passes were more accurate than their first. In addition, independent of sentence length, children increased their inclusion of pronominal and expletive but not lexical subjects. Children included verbs more often from sentences with pronominal than lexical subjects, suggesting a trade-off. Children included subjects more often in short sentences than long ones, and increased subject inclusion only in short sentences. The results suggest that children's language production is similar to adults': a complex interaction of syntactic knowledge, limited cognitive resources, communicative goals, and conversational structure.

Cognitive complexity and complexity of linguistic structure have been found to influence the order of acquisition of locatives. In Warlpiri, locative terms are nominals and they are used in combination with a locative case marker on the reference object; directional affixes may be added to them. Data from a series of tests of Warlpiri children's comprehension and production of the Warlpiri expressions that may be translated as ‘in’, ‘on’, ‘under’, ‘in front of’, ‘behind’ and ‘between’ indicate that the locative case forms are used first without the more specific locative nominals; young children distinguish an ‘up-down’ dimension but not ‘in’, and the reference object influences how the locative term is interpreted; kamparru-pirdangirli (‘front-behind’) is not one dimension for children aged four to five years; kulkurru ‘between’ is understood before kamparru ‘front’ and pirdangirli ‘behind’; the use of features on a reference object for orientation develops at around six, but the orientation of the reference object, as well as features on the placed object may affect interpretation.