Speakers consider their listeners and adjust the way they communicate. One well-studied example is the register of infant-directed speech (IDS), which differs acoustically from speech directed to adults. However, little work has explored how parents adjust speech to infants across different contexts. This is important because infants and parents engage in many activities throughout each day. The current study tests whether the properties of IDS in English vary across three in-lab tasks (sorting objects, free play, and storytelling). We analysed acoustic features associated with prosody, including mean fundamental frequency (F0, perceived as pitch), F0 range, and word rate. We found that both parents’ pitch ranges and word rates varied depending on the task in IDS. The storytelling task stood out among the tasks for having a wider pitch range and faster word rate. The results depict how context can drive parents’ speech adjustments to infants.

English-speaking children sometimes make errors in production and comprehension of biclausal questions, known as “Scope-Marking Errors”. In production, these errors surface as medial wh questions (e.g., What do you think who the cat chased? (Thornton, 1990)). In comprehension, children respond to questions like How did the boy say what he caught? by answering what was caught (de Villiers & Roeper, 1995). These errors resemble wh-scope marking questions, attested in languages like German. Together, these errors suggest temporary adoption of multiple UG-licensed grammars (e.g., Yang, 2002). However, Lutken et al. (2020) found that children who make these errors in production do not necessarily make errors in comprehension and vice versa. They suggest these errors stem from children’s immature processing mechanisms. This article examines children’s production, comprehension, and processing capabilities, specifically working memory (WM). We find a correlation between WM and error rate and suggest separate causes for production and comprehension errors.

A growing body of research has found that talking to young children is positively associated with language outcomes. However, there is tremendous heterogeneity in the design of these studies, which could potentially affect the strength and reliability of this association. The present meta-analysis, comprising 4760 participants across 71 studies, goes beyond prior research by including: 1) more recent studies, 2) non-English-speaking populations, 3) more fine-grained categorization of measures of input, 4) additional moderators, and 5) a multilevel model design allowing us to consider multiple effect sizes per study. We find a moderate association between input and outcomes (R2=0.04-0.07) across four input measures, with some evidence of publication bias. We find no differences in effect size across any of the input measures. Child age and study duration moderated some effects of input. Our findings suggest that language input-outcome associations remain robust but modest across a multitude of contexts and measures.

By comparing infant-directed speech to spouse- and dog-directed talk, we aimed to investigate how pitch and utterance length are modulated by speakers considering the speech context and the partner’s expected needs and capabilities. We found that mean pitch was modulated in line with the partner’s attentional needs, while pitch range and utterance length were modulated according to the partner’s expected linguistic competence. In a situation with a nursery rhyme, speakers used the highest pitch and widest pitch range with all partners suggesting that infant-directed context greatly influences these acoustic features. Recent findings showed that these speakers expressed more intense positive emotions towards their infants and spouses than towards their dogs. Our results revealed different patterns, leading us to conclude that these acoustic features are not simple by-products of emotional speech. Instead, they are dynamically and functionally used in accordance with the speech context and the audience’s expected needs and capabilities.

To investigate how a high risk for infant neurological impairment affects the quality of infant verbal interactions, and in particular properties of infant-directed speech, spontaneous interactions between 14 mothers and their 4.5-month-old infants at high risk for neurological disorders (7 female) were recorded and acoustically compared with those of 14 dyads with typically developing infants (8 female). Mothers of at-risk infants had proportionally less voicing, and the proportion of voicing decreased with increasing severity of the infants’ long-term outcome. Follow-up analysis based on manual annotation of phonation style revealed breathy phonation as more common toward infants with more severe long-term outcomes (N=7; 44.7% of speech) than controls (N=14; 22.0%; p=0.005) or at-risk infants with typical or mildly abnormal long-term outcomes (N=7; 16.5%; p=0.002). The results indicate that maternal phonation style during early dyadic interactions is affected by the infant’s neurological condition.

The Arabic development of Syrian refugee children (N = 133; mean age = 9;4 at Time 1) was examined over 3 time periods during their first five years in Canada. Children were administered sentence repetition and receptive vocabulary tasks in English and Arabic, and information about age-of-arrival (AOA), schooling in Arabic and language environment factors was obtained via parent report. Older AOA was associated with superior Arabic abilities across time, but regardless of AOA, children showed plateau/attrition patterns in Arabic and shifts to English dominance by Time 3. Increases in English over Arabic were observed for language use at home and language-rich activities overtime. Stronger Arabic Time 3 outcomes were predicted by more Arabic and less English use with siblings, more schooling in Arabic, more frequent listening-speaking and extra-curricular activities in Arabic, and more Arabic use with friends. We conclude that the heritage language can be vulnerable even for first-generation bilinguals.

This study explored cognitive effects on narrative macrostructure in both languages of 38 Russian-German bilinguals aged 4;6 to 5;1‚ while controlling for demographic factors (sex, socioeconomic status) and language proficiency. Macrostructure was operationalised as story structure (SS) and story complexity (SC) using the Multilingual Assessment Instrument for Narratives. Nonverbal cognitive subtasks assessing shifting (Figure Ground), visual memory (Form Completion), and inhibition (Attention Divided) were administered. None of the cognitive skills influenced SS; however, they differentially impacted SC: Figure Ground affected Russian SC, while Form Completion affected German SC. Findings advance our understanding of how cognition affects oral narratives in bilingual preschoolers.

Children acquire vocabulary at different growth rates. The aim of this study was to identify subgroups of different vocabulary trajectories in a community sample of L1 German-speaking children aged 1;6 to 3;0 to enlarge the understanding of vocabulary trajectories. Parents filled out vocabulary checklists at four measurement times, each six months apart. Growth mixture modelling was used to naturally determine latent classes of observed vocabulary growth curve patterns. Six distinct trajectories of vocabulary growth were identified and characterised. Children’s (N=198) vocabulary abilities were divided into the following subgroups: “far above average” (2.0%), “above average” (6.6%), “typical” (70.2%), “below average” (14.1%), “early below average" but caught up with their peers over time (5.6%), and “far below average” (1.5%). Socioeconomic status differed significantly between subgroups.

The current study examined the relationship between interest, the home environment, and young Chinese children’s development of English as a second/foreign language in Hong Kong. Two hundred and seventy-four Hong Kong kindergartners were assessed on their interest in learning English and their English language skills (i.e., expressive and receptive vocabulary). Their parents completed questionnaires eliciting family socio-economic status, parental beliefs, and home learning environment. The results indicated that (1) interest was related to children’s English language abilities after controlling for children’s gender, non-verbal intelligence, and kindergarten type; (2) parents’ beliefs about their child’s English ability and self-efficacy were related to children’s interest in learning English; and (3) interest uniquely contributed to children’s English language ability in the home environment. The present findings provide evidence of the active role that children play in their second/foreign language development and highlight the significant influence of parental beliefs on children’s interest in learning English.

Infants’ language is often measured indirectly via parent reports, but mothers may underestimate or overestimate their infants’ word comprehension. The current study examined estimations of mothers from diverse educational backgrounds regarding their infants’ word comprehension and how these estimations are associated with their verbal input and infants’ receptive vocabulary at 14 months. We compared 34 infants’ looking-while-listening (LWL) performances with the mothers’ Turkish Communicative Development Inventory (TCDI) reports to calculate the mothers’ overestimation and underestimation. During free-play sessions, we assessed the mothers’ number of words, number of clauses, lexical diversity, and linguistic complexity. We found that mothers have overestimations and underestimations regardless of their educational background. Crucially, mothers’ only overestimations were positively associated with their number of words and lexical diversity. Mothers’ verbal input was not related to infants’ receptive vocabulary scores. The findings suggest that mothers’ input might be aligned with their estimations of their infants’ language capabilities, which might not reflect the infants’ true performance.

This study investigates Navajo verbs produced by four children, ages 4;07 to 11;02, during conversations with their caretakers. Analyses of 1600 verbs demonstrate that the bisyllabic verb form, consisting of a verb stem and a portion of the prefix string, is the most common pattern produced by the children. This indicates that Navajo-speaking children use meaningful units of verbal morphology that do not necessarily adhere to the linguistic boundaries normally ascribed to the Navajo verb complex. Further, the verbs are primarily intransitive and third-person singular constructions, which are minimally inflected. It is argued that these minimally-inflected verb forms are frequent not just because they are simpler, but also because they are highly productive as main verbs and are used to create phrasal verbs and nouns. These findings contribute to our general understanding of language development and to the growing body of research investigating children’s acquisition of endangered Indigenous languages.

This study investigates Mandarin-speaking children’s (age 3–7) comprehension development of novel and conventional metonymy, combining online and offline methods. Both online and offline data show significantly better performances from the oldest group (6-to-7-year-old) and a delayed acquisition of conventional metonymy compared with novel metonymy. However, part of offline data shows no significant difference between adjacent age groups, while the eye-tracking data show a chronological development from age 3–7. Furthermore, in offline tasks, the three-year-old group features a high choice randomness and the four-to-five-year-olds show the longest reaction time. Therefore, we argue that, not only age but also metonymy type can influence metonymy acquisition, and that a lack of socio-cultural experience can be a source of acquisition difficulty for children under six. Methodologically speaking, we believe that online methods should not be considered superior to offline ones as they investigate different aspects of implicit and explicit language comprehension.

Research shows that children’s home environment (e.g., the composition of their household and the resources available in it) has an impact on children’s language development. However, this research has mostly been conducted among English speakers from the minority world and has often only considered vocabulary size. This exploratory study investigated whether home environment factors are predictive of grammar development in Afrikaans-speaking (n = 117) and English-speaking (n = 102) toddlers in South Africa. Moreover, potential differences between these two language groups were explored. Results showed that home environment factors pertaining to family stability predicted two of the three grammar scores, namely total grammar and complex phrases. Cluster analysis showed distinct patterns of home environment factors between Afrikaans and English-speaking households, illustrating the importance of measuring these factors even across samples from the same country. This study shows that children’s home environment is an interconnected system and cautions against oversimplified single-factor approaches.

Private speech is a tool through which children self-regulate. The regulatory content of children’s overt private speech is associated with response to task difficulty and task performance. Parenting is proposed to play a role in the development of private speech as co-regulatory interactions become represented by the child as private speech to regulate thinking and behaviour. This study investigated the relationship between maternal parenting style and the spontaneous regulatory content of private speech in 3- to 5-year-old children (N = 70) during a problem-solving Duplo construction task. Sixty-six children used intelligible private speech which was coded according to its functional self-regulatory content (i.e., forethought, performance, and self-reflective). Mothers completed the Australian version of the Parenting Styles and Dimensions Questionnaire. Results revealed a significant positive association between maternal authoritative parenting and the frequency and proportion of children’s forethought type (i.e., planning and self-motivational) utterances during the construction task. There were no significant associations between maternal parenting style and other private speech content subtypes.

This study investigated the role of temperament in oral language development in over 200 Mandarin and Cantonese speakers in the Growing Up in New Zealand pre-birth longitudinal cohort study. Mothers assessed infant temperament at nine months using a five-factor Infant Behaviour Questionnaire-Revised Very Short Form. They also reported on children’s vocabulary and word combinations at age two using adapted MacArthur-Bates Communicative Development Inventory short forms. Regression analyses were employed to examine unique links between infant temperament and language, respectively, controlling for demographic factors. Fear was associated with larger English vocabularies for English-Mandarin speakers and larger Cantonese vocabularies for Cantonese speakers. Orienting capacity was associated with more advanced word combinations for Mandarin speakers, whereas negative emotionality was associated with less advanced word combinations for Cantonese speakers. Positive affect/surgency was associated with more advanced word combinations for English-Cantonese speakers. This study revealed predictive patterns of infant temperament across Chinese-speaking children’s multiple languages.

We report findings from a corpus-based investigation of three young children growing up in German-English bilingual environments (M = 3;0, Range = 2;3–3;11). Based on 2,146,179 single words and two-word combinations in naturalistic child speech (CS) and child-directed speech (CDS), we assessed the degree to which the frequency distribution of CDS predicted CS usage over time, and systematically identified CS that was over- or underrepresented in the corpus with respect to matched CDS baselines. Results showed that CDS explained 61% of the variance in CS single-word use and 19.3% of the variance in two-word combinations. Furthermore, the bilingual nature of the over or -underrepresented CS was partially attributable to factors beyond the corpus statistics, namely individual differences between children in their bilingual learning environment. In two out of the three children, overrepresented two-word combinations contained higher levels of syntactic slot redundancy than underrepresented CS. These results are discussed with respect to the role that redundancy plays in producing semiformulaic slot-and-frame patterns in CS.

Both the quantity and quality of the maternal language input are important for early language development. However, depression and anxiety can negatively impact mothers’ engagement with their infants and their infants’ expressive language abilities. Australian mother-infant dyads (N = 30) participated in a longitudinal study examining the effect of maternal language input when infants were 24 and 30 months and maternal depression and anxiety symptoms on vocabulary size. Half the mothers had elevated depression and anxiety symptoms during at least one point in the study (at 6, 12, 18, 24, or 30 months). The results showed that only maternal input measures (word tokens, types, and mean length of utterance) predicted vocabulary size. While no evidence was found that brief periods of maternal depression and anxiety negatively impacted early vocabulary development, the findings highlight the critical importance and possible mitigating effects of maintaining good quality mother–infant interactions during early development.

We characterised language samples collected remotely from typically developing three-year-olds by comparing them against independent language samples collected in person from age-matched peers with and without language delays. Forty-eight typically developing, English-learning three-year-olds were administered a picture description task via Zoom. The in-person comparison groups were two sets of independent language samples from age-matched typically developing as well as language-delayed children available on the Child Language Data Exchange System. The findings show that although language samples collected remotely from three-year-olds yield numerically dissimilar lexical and grammatical measures compared to samples collected in person, they still consistently distinguish toddlers with and without language delays.

This study investigates the interrelationship between gender-shift in child-directed speech (CDS), child gender, and parenting styles among Arabic-speaking caregivers. A survey of 180 Palestinian parents assessed their parenting styles and reported use of gender-shift in relation to their child’s gender. The findings reveal no significant correlation between gender-shift and child’s gender. However, a positive association exists between gender-shift and indulgence, a characteristic of permissive parenting, while a negative correlation is seen with autonomy granting, regulation, and warmth/support, central to authoritative parenting. These results highlight the need for detailed analysis of parenting dimensions towards deeper understanding of the role of gender-shift use in Arabic CDS, suggesting that broader parenting style categories might overlook crucial differences. The study emphasizes the importance of culturally and linguistically sensitive, interprofessional approaches in language development research, especially in relatively unexplored areas like CDS, while also acknowledging the complexities of exploring such relatively unexamined areas.

The present study investigated whether children’s difficulty with non-canonical structures is due to their non-adult-like use of linguistic cues or their inability to revise misinterpretations using late-arriving cues. We adopted a priming production task and a self-paced listening task with picture verification, and included three Mandarin non-canonical structures with differing word orders and the presence or absence of morphosyntactic cues. Forty five-to-ten-year-old Mandarin-speaking children were tested and compared to adults. Results showed that children were indistinguishable from adults in how they used different cues in real-time, although their performance in offline comprehension and production was more prone to errors but improved given the increase of age. These results suggest that the current child sample has adult-like cue-use patterns and use late-arriving cues to revise misinterpretations. The observed worse offline accuracy and production difficulties relative to adults result from their less developed domain-general abilities in performing tasks.