Depression and Anxiety in the Postnatal Period: An Examination of Infants’ Home Language Environment,Vocalizations, and Expressive Language Abilities

This longitudinal study investigated the effects of maternal emotional health concerns, on infants’ home language environment, vocalization quantity, and expressive language skills. Mothers and their infants (at 6 and 12 months; 21 mothers with depression and or anxiety and 21 controls) provided day-long home-language recordings. Compared with controls, risk group recordings contained fewer mother–infant conversational turns and infant vocalizations, but daily number of adult word counts showed no group difference. Furthermore, conversational turns and infant vocalizations were stronger predictors of infants’ 18-month vocabulary size than depression and anxiety measures. However, anxiety levels moderated the effect of conversational turns on vocabulary size. These results suggest that variability in mothers’ emotional health influences infants’ language environment and later language ability.     

The Relation Between Preschoolers’ Vocabulary Development and Their Ability to Predict and Recognize Words

By age 2, children are developing foundational language processing skills, such as quickly recognizing words and predicting words before they occur. How do these skills relate to children’s structural knowledge of vocabulary? Multiple aspects of language processing were simultaneously measured in a sample of 2-to-5-year-olds (N = 215): While older children were more fluent at recognizing words, at predicting words in a graded fashion, and at revising incorrect predictions, only revision was associated with concurrent vocabulary knowledge once age was accounted for. However, an exploratory longitudinal follow-up (N = 55) then found that word recognition and prediction skills were associated with rate of subsequent vocabulary development, but revision skills were not. We argue that prediction skills may facilitate language learning through enhancing processing speed.     

English expressive vocabulary growth and its unique role in predicting English word reading: A longitudinal study involving Hong Kong Chinese ESL children

This longitudinal study examined the developmental trajectory of English expressive vocabulary and its relationship to English word reading in a sample of 141 Hong Kong children learning English as a second language (ESL). The children were observed six times at 3-month intervals over 15 months, from the spring of their second year of kindergarten (K2) to the end of their third year (K3). The development of English expressive vocabulary was nonlinear during the assessment period. With age, nonverbal IQ, English phonological awareness, letter knowledge and Chinese character reading controlled, the initial level of expressive vocabulary predicted English word reading 15 months later. More importantly, the expressive vocabulary growth rate during the 15 months also predicted English word reading. Our findings underscore the predictive power of the growth trajectory of expressive vocabulary in Hong Kong ESL children. Practical implications of the study are discussed.     

Genetic and Environmental Links Between Natural Language Use and Cognitive Ability in Toddlers

Although the phenotypic correlation between language and nonverbal cognitive ability is well‐documented, studies examining the etiology of the covariance between these abilities are scant, particularly in very young children. The goal of this study was to address this gap in the literature by examining the genetic and environmental links between language use, assessed through conversational language samples, and nonverbal cognition in a sample of 3‐year‐old twins (N = 281 pairs). Significant genetic and nonshared environmental influences were found for nonverbal cognitive ability and language measures, including mean length of utterance and number of different words, as well as significant genetic covariance between cognitive ability and both language measures.     

Naturalistic Language Recordings Reveal “Hypervocal” Infants at High Familial Risk for Autism

Children's early language environments are related to later development. Little is known about this association in siblings of children with autism spectrum disorder (ASD), who often experience language delays or have ASD. Fifty‐nine 9‐month‐old infants at high or low familial risk for ASD contributed full‐day in‐home language recordings. High‐risk infants produced more vocalizations than low‐risk peers; conversational turns and adult words did not differ by group. Vocalization differences were driven by a subgroup of “hypervocal” infants. Despite more vocalizations overall, these infants engaged in less social babbling during a standardized clinic assessment, and they experienced fewer conversational turns relative to their rate of vocalizations. Two ways in which these individual and environmental differences may relate to subsequent development are discussed.     

Classroom Age Composition and Vocabulary Development Among At-Risk Preschoolers

Research Findings: The purpose of this exploratory study was to examine the relationship between classroom age composition and preschoolers’ vocabulary gains over an academic year and also to examine whether these relations were moderated by classroom quality. In this study (N = 130 children in 16 classrooms representing a subset of all children enrolled in these classrooms), results showed a significant cross-level interaction between classroom age composition and children's age, suggesting positive effects of greater variance in classroom age composition for younger but not older children. The interaction between behavior management (1 dimension of classroom quality) and classroom age composition was also significant, indicating that a wider distribution of classroom age composition was positively related to children's vocabulary gains within classrooms characterized by better behavior management. Practice or Policy: Findings underscore the importance of children's social interactions with more knowledgeable conversational partners in promoting their vocabulary development and signify the need to help teachers learn how to manage children's behaviors so as to provide a classroom that is optimal for child learning.     

Comparing Automatic and Manual Measures of Parent–Infant Conversational Turns: A Word of Caution

The Language ENvironment Analysis system (LENA) records children’s language environment and provides an automatic estimate of adult–child conversational turn count (CTC). The present study compares LENA’s CTC estimate to manually coded CTC on a sample of 70 English-speaking infants recorded longitudinally at 6, 10, 14, 18, and 24 months of age. At each age, LENA’s CTC was significantly higher than manually coded CTC (all ps < .001, Cohen’s ds: 0.9–2.05), with the largest discrepancies between the two methods observed at younger ages. The Limits of Agreement Analyses confirm wide disagreements between the two methods, highlighting potential problems with automatic measurement of parent–infant verbal interaction. These findings suggest that future studies should validate LENA’s CTC estimates with manual coding.     

Caregiver speech predicts the emergence of children's emotion vocabulary

Learning about emotions is an important part of children's social and communicative development. How does children's emotion-related vocabulary emerge over development? How may emotion-related information in caregiver input support learning of emotion labels and other emotion-related words? This investigation examined language production and input among English-speaking toddlers (16–30 months) using two datasets: Wordbank (N = 5520; 36% female, 38% male, and 26% unknown gender; 1% Asian, 4% Black, 2% Hispanic, 40% White, 2% others, and 50% unknown ethnicity; collected in North America; dates of data collection unknown) and Child Language Data Exchange System (N = 587; 46% female, 44% male, 9% unknown gender, all unknown ethnicity; collected in North America and the UK; data collection dates, were available between 1962 and 2009). First, we show that toddlers develop the vocabulary to express increasingly wide ranges of emotional information during the first 2 years of life. Computational measures of word valence showed that emotion labels are embedded in a rich network of words with related valence. Second, we show that caregivers leverage these semantic connections in ways that may scaffold children's learning of emotion and mental state labels. This research suggests that young children use the dynamics of language input to construct emotion word meanings, and provides new techniques for defining the quality of infant-directed speech.     

Continuity and Change in the Home Literacy Environment as Predictors of Growth in Vocabulary and Reading

One hundred and ten English‐speaking children schooled in French were followed from kindergarten to Grade 2 (M_age: T1 = 5;6, T2 = 6;4, T3 = 6;11, T4 = 7;11). The findings provided strong support for the Home Literacy Model (Sénéchal & LeFevre, 2002 ) because in this sample the home language was independent of the language of instruction. The informal literacy environment at home predicted growth in English receptive vocabulary from kindergarten to Grade 1, whereas parent reports of the formal literacy environment in kindergarten predicted growth in children's English early literacy between kindergarten and Grade 1 and growth in English word reading during Grade 1. Furthermore, 76% of parents adjusted their formal literacy practices according to the reading performance of their child, in support of the presence of a responsive home literacy curriculum among middle‐class parents.     

The Impact of Early Social Interactions on Later Language Development in Spanish–English Bilingual Infants

This study tested the impact of child‐directed language input on language development in Spanish–English bilingual infants (N = 25, 11‐ and 14‐month‐olds from the Seattle metropolitan area), across languages and independently for each language, controlling for socioeconomic status. Language input was characterized by social interaction variables, defined in terms of speech style (“parentese” vs. standard speech) and social context (one‐on‐one vs. group). Correlations between parentese one‐on‐one and productive vocabulary at 24 months (n = 18) were found across languages and in each language independently. Differences are highlighted between previously published monolingual samples, which used the same methods as the current study of bilingual infants. The results also suggest cultural effects on language input and language development in bilingual and bicultural infants.     

Number‐Concept Acquisition and General Vocabulary Development

How is number‐concept acquisition related to overall language development? Experiments 1 and 2 measured number‐word knowledge and general vocabulary in a total of 59 children, ages 30–60 months. A strong correlation was found between number‐word knowledge and vocabulary, independent of the child’s age, contrary to previous results (D. Ansari et al., 2003). This result calls into question arguments that (a) the number‐concept creation process is scaffolded mainly by visuo‐spatial development and (b) that language only becomes integrated after the concepts are created (D. Ansari et al., 2003). Instead, this may suggest that having a larger nominal vocabulary helps children learn number words. Experiment 3 shows that the differences with previous results are likely due to changes in how the data were analyzed.     

Cross‐Linguistic Lexical,Grammatical, and Discourse Performance on Oral Narrative Retells Among Young Spanish Speakers

This study investigated relations among microlevel and macrolevel domains of oral narrative retells within and across the languages of Spanish‐speaking bilingual children. Fifty‐six first and second graders (M_age = 7 years, 3 months) were assessed on a retell task in Spanish and English. Two statistical analyses were conducted: (a) correlations within and across microlevel lexical (number of different words) and grammatical (mean length of utterance‐word and subordination index) domains and (b) hierarchical regression to determine the influence of microlevel domains on a macrolevel discourse score. Results highlighted a number of significant within‐ and cross‐language correlations, and identified vocabulary as a significant predictor of macrolevel discourse scores within both languages, while grammar was a predictor within English only.     

Linking Quality and Quantity of Parental Linguistic Input to Child Language Skills: A Meta-Analysis

This meta-analysis examined associations between the quantity and quality of parental linguistic input and children’s language. Pooled effect size for quality (i.e., vocabulary diversity and syntactic complexity; k = 35; N = 1,958; r = .33) was more robust than for quantity (i.e., number of words/tokens/utterances; k = 33; N = 1,411; r = .20) of linguistic input. For quality and quantity of parental linguistic input, effect sizes were stronger when input was observed in naturalistic contexts compared to free play tasks. For quality of parental linguistic input, effect sizes also increased as child age and observation length increased. Effect sizes were not moderated by socioeconomic status or child gender. Findings highlight parental linguistic input as a key environmental factor in children’s language skills.     

Home Language and Literacy Environments and Early Literacy Trajectories of Low-Socioeconomic Status Chilean Children

This study used Latent Class Analysis to identify groups of children exposed to similar Home Language and Literacy Environments (HLLE) and explored whether belonging to a given HLLE group was related to children’s language and early literacy growth from prekindergarten to kindergarten. Participants were 1,425 Chilean mothers and their children (M_age = 52.52 months at baseline) from low-socioeconomic status households. Four HLLE groups were identified, which were associated with different trajectories of language and early literacy development. Children from groups whose mothers either read and talk about past events with them or teach them letters in addition to reading and talking about past events, showed higher relative vocabulary and letter knowledge. Implications for research and interventions are discussed.     

Peer Effects on Early Language Development in Dual Language Learners

This study investigated the vocabulary development of children (N = 547) from linguistically and socioeconomically diverse classrooms in Germany from age 3 in preschool to age 7 in Grade 1. The results showed that for dual language learners (DLLs, n = 107) growth rates in their German majority language skills varied over classrooms. Compared to monolingual children, DLLs improved faster in classrooms with higher peer-level skills in the majority language than DLLs in classrooms with lower peer-level skills (controlling for socioeconomic status and classroom quality). DLLs showed stronger growth dynamics than monolingual children during later preschool stages. The findings highlight the role of preschool peers in DLLs’ acquisition of the majority language before entering elementary school.     

A Cross-Cultural Analysis of Early Prelinguistic Gesture Development and Its Relationship to Language Development

Many Western industrialized nations have high levels of ethnic diversity but to date there are very few studies which investigate prelinguistic and early language development in infants from ethnic minority backgrounds. This study tracked the development of infant communicative gestures from 10 to 12 months (n = 59) in three culturally distinct groups in the United Kingdom and measured their relationship, along with maternal utterance frequency and responsiveness, to vocabulary development at 12 and 18 months. No significant differences were found in infant gesture development and maternal responsiveness across the groups, but relationships were identified between gesture, maternal responsiveness, and vocabulary development.     

How Early Maternal Language Input Varies by Race and Education and Predicts Later Child Language

The maternal language input literature suggests that mothers with more education use a greater quantity and complexity of language with their young children compared to mothers with less education although race and socioeconomic status have been confounded in most studies because of small sample sizes. The current Family Life study included a representative sample of 1,292 children, oversampling for poverty and African American, followed from birth. This study found no race differences within maternal education levels on five measures of maternal language input from 6 to 36 months. Maternal language input variables of number of different words, mean length of utterance and number of wh-questions were partial mediators of the relationship between maternal education and later child language at school age.     

Preschoolers rely on rich speech representations to process variable speech

To learn language, children must map variable input to categories such as phones and words. How do children process variation and distinguish between variable pronunciations (“shoup” for soup) versus new words? The unique sensory experience of children with cochlear implants, who learn speech through their device's degraded signal, lends new insight into this question. In a mispronunciation sensitivity eyetracking task, children with implants (N = 33), and typical hearing (N = 24; 36–66 months; 36F, 19M; all non-Hispanic white), with larger vocabularies processed known words faster. But children with implants were less sensitive to mispronunciations than typical hearing controls. Thus, children of all hearing experiences use lexical knowledge to process familiar words but require detailed speech representations to process variable speech in real time.     

Reexamining the Verbal Environments of Children From Different Socioeconomic Backgrounds

Amid growing controversy about the oft-cited “30-million-word gap,” this investigation uses language data from five American communities across the socioeconomic spectrum to test, for the first time, Hart and Risley's (1995) claim that poor children hear 30 million fewer words than their middle-class counterparts during the early years of life. The five studies combined ethnographic fieldwork with longitudinal home observations of 42 children (18–48 months) interacting with family members in everyday life contexts. Results do not support Hart and Risley's claim, reveal substantial variation in vocabulary environments within each socioeconomic stratum, and suggest that definitions of verbal environments that exclude multiple caregivers and bystander talk disproportionately underestimate the number of words to which low-income children are exposed.