The relationship between language development and the development of non-verbal representation was studied longitudinally in six children. Language development is evaluated interactionally by considering not only the form and usage of a child's sounds but also the way a familiar person allows those sounds to function as instances of words belonging to the frequently revised language proper to the child–adult pair. Non-verbal representation, studied in a symbolic play situation, presents different behavioural levels, showing close synchrony with a large increase observed in language development. The results are taken as suggestive of an inter-relational hypothesis between language and non-verbal representation, and an interpretation in terms of reciprocal interaction is proposed.

Three factors have been hypothesized to play an important role in the reduction of children's initial overextensions: spontaneous adult use of the correct label, correction of the child's errors, and demonstration of the important attributes that make an object a member of its adult category. The role of these factors was examined in relation to data collected from a longitudinal study of early lexical development. This study used an observational methodology combined with systematic comprehension and production testing. Results indicated that demonstrations were the most important factor in inducing toddlers to assign an object to its adult category. The question of why purely linguistic input initially plays a minor role in changing children's categories is discussed.

The aim of this study was to determine whether children with specific language impairment (SLI) are sensitive to completion cues in their comprehension of tense. In two experiments, children with SLI (ages 4 ; 1 to 6 ; 4) and typically developing (TD) children (ages 3 ; 5 to 6 ; 5) participated in a sentence-to-scene matching task adapted from Wagner (2001). Sentences were in either present or past progressive and used telic predicates. Actions were performed twice in succession; the action was either completed or not completed in the first instance. In both experiments, the children with SLI were less accurate than the TD children, showing more difficulty with past than present progressive, regardless of completion cues. The TD children were less accurate with past than present progressive requests only when the past actions were incomplete. These findings suggest that children with SLI may be relatively insensitive to cues pertaining to event completion in past tense contexts.

Natural speech of 32 young children from 2; 0 to 3; 1 (1·97 to 6·38 in MLU) was studied for evidence of use of coordination (by and). Analyses of the structure of coordinative expressions reflected development in structural variants as well as amount of coordination. Analyses suggested that early forms of coordination in natural speech reflected the same constraints which had been suggested by previous study of these children's language through an experimental elicited imitation task. A basis for a developmental theory of acquisition of coordination is sketched.

This study provides the first systematic account of word-final cluster acquisition in bilingual children. To this end, forty Welsh–English bilingual children differing in language dominance and age (2;6 to 5;0) participated in a picture-naming task in English and Welsh. The results revealed significant age and dominance effects on cluster acquisition, with greater overall accuracy on the English clusters. Interestingly, although the Welsh-dominant children outperformed the English-dominant ones on the Welsh clusters, they did not exhibit a concomitant lag on the English clusters. It is argued that this asymmetry is a direct reflection of the sociolinguistic situation in Wales with English as the majority language and Welsh the minority language. The study also revealed accelerated rates of acquisition for English clusters compared with age-matched monolinguals reported elsewhere (Templin, 1957), thereby supporting claims that bilingual contexts may have a facilitative effect on phonological acquisition (Goldstein & Bunta, 2012; Grech & Dodd, 2008).

This study set out to examine whether shyness, an aversion to novelty and unfamiliar social situations, can affect the processes that underlie early word learning. Twenty-four-month-old children (n =32) were presented with sets of one novel and two familiar objects, and it was found that shyer children were less likely to select a novel object as the referent of a novel label. Furthermore, not-shy children then showed evidence of retaining these novel mappings, but shy children did not. These findings suggest that shy children's aversion to novelty and to the unfamiliar context can impact on their word learning.

The present study1 exposed five-year-olds (M=5 ; 2), seven-year-olds (M=7 ; 6) and adults (M=22 ; 4) to instances of a novel phrasal construction, then used a forced choice comprehension task to evaluate their learning of the construction. The abstractness of participants' acquired representations of the novel construction was evaluated by varying the degree of lexical overlap that test items had with exposure items. We found that both child groups were less proficient than adults, but seven-year-olds showed evidence of across-the-board generalization whereas five-year-olds were sensitive to lexical overlap at test. This outcome is consistent with more conservative, item-based learning of syntactic patterns in younger children. Additionally, unlike adults and seven-year-olds, five-year-olds showed no evidence of having mastered the novel construction's linking rules. Thus, younger learners are less likely to generalize abstract argument structure constructions when exposed to the same systematic input as older learners.

Agreement is a morphosyntactic dependency which is sensitive to the hierarchical structure of the clause and is constrained by the structural distance that separates the elements involved in this relation. In this paper we present two experiments, providing new evidence that Italian-speaking children with Developmental Language Disorder (DLD), as well as Typically Developing (TD) children, are sensitive to the same hierarchical and locality factors that characterise agreement in adult grammars. This sensitivity holds even though DLD children show accrued difficulties in more complex agreement configurations. In the first experiment, a forced-choice task was used to establish whether children are more affected in the computation of S-V agreement when an element intervenes hierarchically or linearly in the agreement relation: DLD children are more subject to attraction errors when the attractor intervenes hierarchically, indicating that DLD children discriminate between hierarchical and linear configurations. The second experiment, also conducted through a forced-choice task, shows that the computation of agreement in DLD children is more ‘fragile’ than in TD children (and also in children with a primary impairment in the phonological domain), in that it is more sensitive to the factors of complexity identified in Moscati and Rizzi's (2014) typology of agreement configurations. To capture the agreement pattern found in DLD children, we put forth a novel hypothesis: the Fragile Computation of Agreement Hypothesis. Its main tenet is that DLD children make use of the same grammatical operations employed by their peers, as demonstrated in Experiment 1, but difficulties increase as a function of the complexity of the agreement configuration.

This study tests the hypothesis that developmental dyslexia is (partly) caused by a deficit in implicit sequential learning, by investigating whether infants at familial risk of dyslexia can track non-adjacent dependencies in an artificial language. An implicit learning deficit would hinder detection of such dependencies, which mark grammatical relations (e.g. between ‘is’ and ‘-ing’ in ‘she is happily singing’). In a head-turn experiment with infants aged 1;6, family risk and typically developing infants were exposed to one of two novel languages containing dependencies of the type a-X-c, b-X-d or a-X-d, b-X-c, with fixed first and third elements and twenty-four different X elements. During test, typically developing children listened longer to ungrammatical strings (i.e. that did not correspond to their training language). However, family-risk children did not discriminate between grammatical and ungrammatical strings, indicating deficient implicit learning. The implications of these findings in relation to dyslexia and other language-based disorders are discussed.

This study examines the influence of bilingual status, language-internal (complexity of L1 phonology), language-external (dominance), and lexical (L2 vocabulary score) factors on phonological production in French-speaking monolingual (n = 37) and bilingual children (n = 64) aged three to six years. Children participated in an object and picture naming task which tested different phonological features. The bilinguals’ first languages were coded in terms of the complexity of these phonological features. In addition, the parents completed a questionnaire on their child's language dominance and the children were administered a vocabulary test in their L2. Results indicated that vocabulary was the principal predictor of phonological accuracy across both age groups. Apparent monolingual–bilingual differences and dominance effects could largely be explained by vocabulary scores: children who scored better on a vocabulary test obtained superior phonological accuracy. Language-internal effects were minimal and marginally influenced vowel accuracy only.

Children pass through a stage in development when they produce utterances that contain auxiliary BE (he's playing) and utterances where auxiliary BE is omitted (he playing). One explanation that has been put forward to explain this phenomenon is the presence of questions in the input that model S-V word order (Theakston, Lieven & Tomasello, 2003). The current paper reports two studies that investigate the role of the input in children's use and non-use of auxiliary BE in declaratives. In Study 1, 96 children aged from 2 ; 5 to 2 ; 10 were exposed to known and novel verbs modelled in questions only or declaratives only. In Study 2, naturalistic data from a dense database from a single child between the ages of 2 ; 8 to 3 ; 2 were examined to investigate the influence of (1) declaratives and questions in the input in prior discourse, and (2) the child's immediately previous use of declaratives where auxiliary BE was produced or omitted, on his subsequent use or non-use of auxiliary BE. The results show that in both the experimental and naturalistic contexts, the presence of questions in the input resulted in lower levels of auxiliary provision in the children's speech than in utterances following declaratives in the input. In addition, the children's prior use or non-use of auxiliary BE influenced subsequent use. The findings are discussed in the context of usage-based theories of language acquisition and the role of the language children hear in their developing linguistic representations.

All uses of the connective but by narrating children 3; 6 to 9; 6 were classified as having primarily semantic function, pragmatic function, or as errors. The youngest children make the majority of errors, mistakenly using but when causal or precausal relationships exist. All children most commonly use but to signal semantic relationships such as semantic opposition or violation of expectation, although the oldest children use but proportionately more to encode more complex contrasts. However, children at all ages also use but for primarily pragmatic functions, to interrupt the flow of their narrative in order to insert relevant comments, monitor the listener's attention, or change topic. If discourse can be conceptualized as having multiple levels, but signals a change in level within a speaker's turn.

This study assessed the status of te reo Māori, the indigenous language of New Zealand, in the context of New Zealand English. From a broadly representative sample of 6327 two-year-olds (Growing Up in New Zealand), 6090 mothers (96%) reported their children understood English, and 763 mothers (12%) reported their children understood Māori. Parents completed the new MacArthur-Bates Communicative Development Inventory short forms for te reo Māori (NZM: CDI sf) and New Zealand English (NZE: CDI sf). Mothers with higher education levels had children with larger vocabularies in both te reo Māori and NZ English. For English speakers, vocabulary advantages also existed for girls, first-borns, monolinguals, those living in areas of lower deprivation, and those whose mothers had no concerns about their speech and language. Because more than 99% of Māori speakers were bilingual, te reo Māori acquisition appears to be occurring in the context of the acquisition of New Zealand English.

This study investigates the influence of the quantity, content, and context of screen media use on the language development of 85 Saudi children aged 1 to 3 years. Surveys and weekly event-based diaries were employed to track children’s screen use patterns. Language development was assessed using JISH Arabic Communicative Development Inventory (JACDI). Findings indicate that the most significant predictor of expressive and receptive vocabulary in 12- to 16-month-olds was screen media context (as measured by the frequency of interactive joint media engagements). In older children (17- to 36-month-olds), more screen time (as measured by the amount of time spent using screens, the prevalence of background TV at home, and the onset age of screen use) had the highest negative impact on expressive vocabulary and mean length of utterance. These findings support health recommendations on the negative effects of excessive screen time and the positive effects of co-viewing media with children.

Three groups of children, aged 5, 7 and 11 years, were tested in a clause-memory task, in order to investigate the role of syntactic and semantic factors in children's recall and processing of spoken continuous prose. The children listened to a story, which was interrupted at intervals during which they were asked to repeat verbatim the last sentence they heard. The test-sentences always consisted of two clauses: either of the main–main type, or of the main–subordinate or subordinate–main types. The prose material was also either normal prose, or semantically uninterpretable but syntactically normal prose. The results suggest a developmental sequence in which the youngest group's performance is dominated by semantic factors. They do not show the adult clause-memory effects, their recall is dominated by the main clause, and their recall of normal prose is not clausally segmented. The two older groups' performance more closely approximates that of adults.

Seventy-five children, 3, 4, and 5 years old, were interviewed about: (a) toys they had played with just a few minutes earlier, (b) toys they had played with on the preceding day, (c) toys they would play with in a few minutes, and (d) toys reserved for use on the following day. Verb forms indicating past and future time were used as well as the adverbials before and after. The past verb form was understood equally well in reference to the immediate past and the more remote past. However, the future verb form was better understood in reference to the immediate future than in reference to the remote future (the following day). The difference is discussed in terms of the intersection of time and mood in future verb forms. Immediacy of action and certainty of occurrence are suggested as early meaning components of future verb forms.

Aims: Although IDS is typically described as slower than adult-directed speech (ADS), potential impacts of slower speech on language development have not been examined. We explored whether IDS speech rates in 42 mother–infant dyads at four time periods predicted children's language outcomes at two years. Method: We correlated IDS speech rate with child language outcomes at two years, and contrasted outcomes in dyads displaying high/low rate profiles. Outcomes: Slower IDS rate at 7 months significantly correlated with vocabulary knowledge at two years. Slowed IDS may benefit child language learning even before children first speak.

This study reports on language outcomes at eight years from the Bucharest Early Intervention Project, a randomized controlled study of foster care. We previously have shown that children placed in foster care by age two have substantially stronger preschool language outcomes than children placed later and children remaining in institutional care. One hundred and five children participated in the current study, fifty-four originally assigned to foster care and fifty-one to continued institutional care. Even though current placements varied, children originally in foster care had longer sentences and stronger sentence repetition and written word identification. Children placed in foster care by age two had significant advantages in word identification and nonword repetition; children placed by age 1 ; 3 performed equivalently to community peers. The results show the continuing adverse effects of early poor institutional care on later language development and the key importance of age of placement in a more optimal environment.

We suggest that preschoolers’ frequent obliviousness to the risks and opportunities of deception comes from a trusting stance supporting verbal communication. Three studies (N = 125) confirm this hypothesis. Three-year-olds can hide information from others (Study 1) and they can lie (Study 2) in simple settings. Yet when one introduces the possibility of informing others in the very same settings, three-year-olds tend to be honest (Studies 1 and 2). Similarly, four-year-olds, though capable of treating assertions as false, trust deceptive informants (Study 3). We suggest that children's reduced sensitivity to the opportunities of lying, and to the risks of being lied to might help explain their difficulties on standard false belief tasks.