This study examines Lithuanian children's acquisition of gender agreement using an elicited production task. Lithuanian is a richly inflected Baltic language, with two genders and seven cases. Younger (N=24, mean 3 ; 1, 2 ; 5–3 ; 8) and older (N=24, mean 6 ; 3, 5 ; 6–6 ; 9) children were shown pictures of animals and asked to describe them after hearing the animal's name. Animal names differed with respect to familiarity (novel vs. familiar), derivational status (diminutive vs. simplex) and gender (masculine vs. feminine). Analyses of gender-agreement errors based on adjective and pronoun usage indicated that younger children made more errors than older children, with errors more prevalent for novel animal names. For novel animals, and for feminine nouns, children produced fewer errors with nouns introduced in diminutive form. These results complement findings from several Slavic languages (Russian, Serbian and Polish) that diminutives constitute a salient cluster of word forms that may provide an entry point for the child's acquisition of noun morphology.

The primary goal was to specify the impact of scaffolding and overhearing on young children's use of the spatial terms between and middle. Four- and five-year-old children described the location of a mouse hidden between two furniture items in a dollhouse with assistance from a parent. Children's use of between and middle increased significantly across trials, and in concert, parents' directive scaffolding involving middle decreased across trials. In the second study, three common scaffolding types (Between Directive, Middle Directive, non-directive) were compared with a no prompt condition by having children receive prompts from a doll and with overhearing conditions in which children overheard conversations between two adult experimenters containing between or middle. Children's use of between and middle was much more frequent following directive prompting than following non-directive prompting, no prompting, or overhearing. Moreover, children showed some evidence of using between and middle in response to non-directive prompting and overhearing.

This paper presents an experiment that examined two related questions. First, it examined the effects of animacy on the production of different syntactic structures and word orders by Catalan-speaking children. Secondly, it explored the relationship between age and the production of different syntactic structures by these children. The results of a picture description experiment run with eighty Catalan-speaking children aged 4; 11 to 11; 11 show that participants tended to produce more object- dislocated descriptions when the patient was animate than when the patient was inanimate. The results also show that while the dislocation of object clauses is a construction already consolidated at 5; 0, the passive structure is a construction still not fully acquired at 11; 0. A comparison between the results obtained in the present experiment with existing results from similar experiments with English-speaking children shows that there is a cross-language difference in the age at which children start producing passive clauses. We argue that frequency of exposure to a particular syntactic structure is an important factor that contributes to the acquisition of that syntactic structure. We also suggest that the effects of animacy on the production of object-dislocated descriptions can be explained by means of conceptual and lexical accessibility.

Canonical syllables may be important units in early speech perception as well as production. Twenty infants (mean age 51 hours) (and twenty controls) were tested for their ability to discriminate between members of syllable pairs which were either canonical (pæt and tæp) or non-canonical (pst and tsp). A discrimination learning method was used in which syllables signalled the availability of either a recording of the mother's voice or silence – one of which was presented if the infant began a sucking burst. Infants in the canonical condition changed sucking patterns during signals over an 18-minute experimental session and activated their mother's voice more than silence, consistent with previous experiments using mother's voice as a reinforcer. In the non-canonical condition, infants also changed sucking patterns but sucked more during the signal for quiet than mother's voice, contrary to previous findings. Differential sucking during the syllables indicated discrimination in both conditions, but infants responded differently depending upon whether the syllables were canonical or non-canonical. The activation of silence in the non-canonical condition may be the result of a preference for quiet, but it is better explained as a failure to progress to a level of differential responding that was reached by the canonical group.

This study investigated vocabulary size and vocabulary composition in Greek children aged 1 ; 6 to 2 ; 11 using a Greek adaptation of Rescorla's Language Development Survey (LDS; Rescorla, 1989). Participants were 273 toddlers coming from monolingual Greek-speaking families. Greek LDS data were compared with US LDS data obtained from the instrument's normative sample (Achenbach & Rescorla, 2000). Vocabulary size increased markedly with age, but Greek toddlers appeared to get off to a slower start in early word learning than US children. The correlation between percentage word use scores in Greek and US samples was moderate in size, indicating considerable overlap but some differences. Common nouns were the largest category among the fifty most frequent words in both samples. Numbers of adjectives and verbs were comparable across languages, but people and closed-class words were more numerous in the Greek sample. Finally, Greek late talkers showed similar patterns of vocabulary composition to those observed in typically developing Greek children.

Two studies of children's early language comprehension were performed using the signal detection paradigm introduced by Thomas et al. (1981). Experiment 1 replicated the original findings of Thomas et al., demonstrating that 13-month-olds understand a word that a parent reported they would understand and did not understand a word that a parent reported they would not. In Experiment 2, the procedure was modified to test for overextensions in early language comprehension. On half of the trials, children saw an array of objects including a referent for a ‘known word’. On the other half, the array included an object perceptually similar to the referent of the known word, but which itself was not an appropriate referent (e.g. an apple instead of an orange). Though the children demonstrated an understanding of the known word, they also overextended that word to the inappropriate referent. Mechanisms for such overextensions are discussed, as is the general relationship between comprehension and production.

The present investigation examined the relationship between attribute saliency and metaphor interpretation in school children. Ortony's theory that metaphors entail salience imbalance prompted the generation of two types of metaphors, PREDICATE-PROMOTING (PP) and PREDICATE-INTRODUCING (PI) metaphors. An adult sample was used to select metaphors of each type which were then presented to 24 children in each of grades three, five, and seven (mean ages 8; 5, 10; 6 and 12; 8). The children were asked to generate attribute lists for TOPIC and VEHICLE terms and, six weeks later, to verbally explain metaphors containing those terms. Older children correctly interpreted more metaphors than younger children, and at each grade level no difference was observed between the number of correct interpretations of PP and PI metaphors. In addition, at all grade levels the incorrect ground of each child's interpretation errors most often had been listed in his/her attribute lists. This suggests that attribute saliency for the individual perceiving the metaphor plays a key role in the interpretation process.

This paper lays out the components of a language acquisition model, the interconnections among the components, and the differing stances of nativism and empiricism about syntax. After demonstrating that parsimony cannot decide between the two stances, the paper analyzes nine examples of evidence that have been used to argue for or against nativism, concluding that most pieces of evidence are either irrelevant or suggest that language is special but need not invoke innate ideas. Two pieces of evidence – the development of home sign languages and the acquisition of Determiners – do show not just that language is special but that the child has innate syntactic content. The existential claim that nativism makes – there is at least one innate syntactic idea – is an easier claim to verify than the universal claim that empiricism makes – there are no innate syntactic ideas.

This study determined at what age and in what form children (aged 4;5 to 11;11) produce speech acts which commit them to some future action, by having them speak a doll's part in dialogues with the experimenter, who spoke for another doll. All children produced directive speech acts, indicating that the task was not too difficult for them, but only the commissive speech acts were analysed in detail. A majority of children at all ages produced at least one commissive speech act, but only the older children used the explicit performative verb promise to reassure the hearer of their commitment.

This paper examines the acquisition of the grammatical tone system of Sesotho, a southern Bantu language where tone sandhi is rich, and where surface and underlying representations are often quite distinct. Results of the longitudinal case study show that rule-assigned tone on subject markers is generally marked appropriately by age two. In contrast, underlying tonal representations on verb roots are learned gradually over time, showing an early Default High tone pattern. The study also finds that, while some tone sandhi rules are in the process of being acquired between 2;6 and 3;0, problems in the mapping between tonal representations and segments persist. The paper raises methodological and theoretical issues not only for the acquisition of tonal systems, but for the acquisition of phonology in general.

The Cantonese language has a complex classifier system and young learners need to pay attention to both the semantics and syntax of classifiers. This study investigated the repertoire of classifiers produced by 492 Cantonese-speaking preschoolers in three age groups (3;0, 4;0 and 5;0). Spontaneous utterances produced in 30-minute toy-play contexts were collected and transcribed. Analyses identified a productive repertoire of 73 classifiers in the utterances, which could be appropriately classified into the typology proposed in the present study. An age-related increase in the number of classifier types per child as well as the repertoire size of each group was found. 個 go3 (CL) was widely used as the general classifier by the young children. It was also discovered that the three-year-olds were already showing signs of grasping the basic syntax of classifiers. Cognitive, linguistic and contextual influences presumed to shape the evidence are discussed.

Code-switching is a common phenomenon in bilingual communities, but little is known about bilingual parents’ code-switching when speaking to their infants. In a pre-registered study, we identified instances of code-switching in day-long at-home audio recordings of 21 French–English bilingual families in Montreal, Canada, who provided recordings when their infant was 10 and 18 months old. Overall, rates of infant-directed code-switching were low, averaging 7 times per hour (6 times per 1,000 words) at 10 months and increasing to 28 times per hour (18 times per 1,000 words) at 18 months. Parents code-switched more between sentences than within a sentence; this pattern was even more pronounced when infants were 18 months than when they were 10 months. The most common apparent reasons for code-switching were to bolster their infant's understanding and to teach vocabulary words. Combined, these results suggest that bilingual parents code-switch in ways that support successful bilingual language acquisition.

It is widely agreed that learning to read starts with the establishment of letter-to-phoneme correspondences. However, it is also widely agreed that prereaders do not have access to phoneme units. Here we show that the building of associations between letters and syllables, which we call the ‘syllabic bridge’, might be a faster and more direct way of learning spelling-to-sound correspondences in French. After a few minutes of exposure, prereaders are able to learn the statistical properties of letter co-occurrences. Statistical learning is boosted by explicit instructions about the associations between letter clusters and syllables. Building the syllabic bridge from available phonological syllables and frequent letter clusters may therefore be the first step in learning to read.

Ten mothers were observed prospectively, interacting with their infants aged 0 ; 10 in two contexts (picture description and noun description). Maternal communicative behaviours were coded for volubility, gestural production and labelling style. Verbal labelling events were categorized into three exclusive categories: label only; label plus deictic gesture; label plus iconic gesture. We evaluated the predictive relations between maternal communicative style and children's subsequent acquisition of ten target nouns. Strong relations were observed between maternal communicative style and children's acquisition of the target nouns. Further, even controlling for maternal volubility and maternal labelling, maternal use of iconic gestures predicted the timing of acquisition of nouns in comprehension. These results support the proposition that maternal gestural input facilitates linguistic development, and suggest that such facilitation may be a function of gesture type.

How do infants find the words in the speech stream? Computational models help us understand this feat by revealing the advantages and disadvantages of different strategies that infants might use. Here, we outline a computational model of word segmentation that aims both to incorporate cues proposed by language acquisition researchers and to establish the contributions different cues can make to word segmentation. We present experimental results from modified versions of Venkataraman's (2001) segmentation model that examine the utility of: (1) language-universal phonotactic cues; (2) language-specific phonotactic cues which must be learned while segmenting utterances; and (3) their combination. We show that the language-specific cue improves segmentation performance overall, but the language-universal phonotactic cue does not, and that their combination results in the most improvement. Not only does this suggest that language-specific constraints can be learned simultaneously with speech segmentation, but it is also consistent with experimental research that shows that there are multiple phonotactic cues helpful to segmentation (e.g. Mattys, Jusczyk, Luce & Morgan, 1999; Mattys & Jusczyk, 2001). This result also compares favorably to other segmentation models (e.g. Brent, 1999; Fleck, 2008; Goldwater, 2007; Johnson & Goldwater, 2009; Venkataraman, 2001) and has implications for how infants learn to segment.

This paper reports the results of a longitudinal case study examining the acquisition of the English voice system by a three-year-old native speaker of Dutch. The study aims to examine whether the child develops two different phonetic systems or uses just one system for both languages, and compares the early L2 acquisition process with L1, simultaneous bilingual and late L2 acquisition. The results reveal that the child successfully acquires the English contrast between short-lag and long-lag stops, but gradually changes the Dutch system, which contrasts prevoiced with short-lag stops, into the direction of the English system.

The Cross-linguistic Lexical Task (CLT; Haman, Łuniewska & Pomiechowska, 2015) is a vocabulary task designed to enable cross-linguistic comparisons both across and within (bilingual) children. In this paper we assessed the validity of the CLT as a measure of language proficiency in bilingual children, by determining the extent to which (i) age-matched, monolingual Spanish-speaking and Dutch-speaking children obtained similar scores, (ii) the CLT correlated with other measures of language proficiency in monolingual and bilingual children, and (iii) whether the factors underlying the CLT's construction, i.e., target words’ estimated Age of Acquisition and Complexity Index, were predictive of children's scores. Our results showed that, while the CLT correlated with other measures and is therefore a valid means of tapping into language proficiency, caution is required when using it to compare children's language proficiency cross-linguistically, as scores for Dutch-speaking and Spanish-speaking monolinguals sometimes differed.

The temporal organization of the late babbling of a French child during the pivotal period between babbling and the production of meaningful utterances is studied. Two points are analysed: the segmental timing in terms of syllabic durations and the durations of sequences according to their intonational contours. Articulation rate in late babbling is fairly rapid and stable and does not vary with length of sequences. However, at the end of the period studied, longer durations are found for bi- and tri-syllabic sequences. This lengthening can be seen to reflect changes in the child's target programming and the constraints on co-articulation that it implies. Additional changes occur also as a function of intonational contours.

The aim of this study was to uncover factors accounting for the ability of children with specific language impairment (SLI) to learn agreement morphemes in intervention. Twenty-five children with SLI who participated in a six-month intervention program focused on teaching third person singular -s or auxiliary is/are/was showed a wide range of use of the target morpheme after intervention. Regression analyses showed that age and two factors expected to be related to agreement – the use of noun plural -s and subject/verb constructions prior to intervention – significantly predicted progress in the acquisition of agreement morphemes. In contrast, the pretreatment use of morphemes hypothesized to be unrelated to agreement was not a significant predictor of progress. The results indicate that the ability of children with SLI to learn agreement morphemes relies on their prior ability to use noun plural and subject/verb constructions.