Erika Hoff

The Specificity of Environmental Influence: Socioeconomic Status Affects Early Vocabulary Development Via Maternal Speech

The hypothesis was tested that children whose families differ in socioeconomic status (SES) differ in their rates of productive vocabulary development because they have different language-learning experiences. Naturalistic interaction between 33 high-SES and 30 mid-SES mothers and their 2-year-old children was recorded at 2 time points 10 weeks apart. Transcripts of these interactions provided the basis for estimating the growth in childrens productive vocabularies between the first and second visits and properties of maternal speech at the first visit. The high-SES children grew more than the mid-SES children in the size of their productive vocabularies. Properties of maternal speech that differed as a function of SES fully accounted for this difference. Implications of these findings for mechanisms of environmental influence on child development are discussed.

How children use input to acquire a lexicon.

The contributions of social processes and computational processes to early lexical development were evaluated. A re-analysis and review of previous research cast doubt on the sufficiency of social approaches to word learning. An empirical investigation of the relation of social-pragmatic and data-providing features of input to the productive vocabulary of sixty-three 2-year-old children revealed benefits of data provided in mother-child conversation, but no effects of social aspects of those conversations. The findings further revealed that the properties of data that benefit lexical development in 2-year-olds are quantity, lexical richness, and syntactic complexity. The nature of the computational mechanisms implied by these findings is discussed. An integrated account of the roles of social and computational processes to lexical development is proposed.

Person-Centered and Variable-Centered Approaches to Longitudinal Data

As the number and scope of longitudinal investigations have expanded, so too have strategies for analyzing prospective data. Different analytic techniques are designed to answer different types of research questions. Person-centered approaches identify groups of individuals who share particular attributes or relations among attributes. They are well suited for addressing questions that concern group differences in patterns of development. Variable-centered approaches describe associations between variables. They are well suited for addressing questions that concern the relative contributions that predictor variables make to an outcome. This special issue includes conceptual essays and empirical reports designed to demonstrate the complementary strengths of these two different approaches. The articles illustrate how the integration of person-oriented and variable-oriented approaches can lead to a more complete understanding of the processes and patterns of human development.

Interpreting the Early Language Trajectories of Children From Low-SES and Language Minority Homes: Implications for Closing Achievement Gaps

On average, children from low socioeconomic status (SES) homes and children from homes in which a language other than English is spoken have language development trajectories that are different from those of children from middle-class, monolingual English-speaking homes. Children from low-SES and language minority homes have unique linguistic strengths, but many reach school age with lower levels of English language skill than do middle-class, monolingual children. Because early differences in English oral language skill have consequences for academic achievement, low levels of English language skill constitute a deficit for children about to enter school in the United States. Declaring all developmental trajectories to be equally valid would not change the robust relation between English oral language skills and academic achievement and would not help children with poor English skills to be successful in school. Remedies aimed at supporting the development of the English skills required for academic success need not and should not entail devaluing or diminishing childrens other language skills.

Properties of dual language exposure that influence 2-year-olds' bilingual proficiency.

The mothers of 29 Spanish English bilingual 25-month-olds kept diary records of their childrens dual language exposure and provided information on their childrens English and Spanish language development using the MacArthur-Bates inventories. Relative amount of exposure predicted language outcomes in English and Spanish. In addition, the number of different speakers from whom the children heard English and the percent of their English input that was provided by native speakers were unique sources of variance in childrens English skills. These properties of childrens dual language exposure and their bilingual proficiency varied as a function of whether the childrens mother, father, or both parents were native Spanish speakers. Practical and theoretical implications are discussed.

Flexibility in early verb use : evidence from a multiple-n diary study

Flexibility and productivity are hallmarks of human language use. Competent speakers have the capacity to use the words they know to serve a variety of communicative functions, to refer to new and varied exemplars of the categories to which words refer, and in new and varied combinations with other words. When and how children achieve this flexibility and when they are truly productive language users--are central issues among accounts of language acquisition. The current study tests competing hypotheses of the achievement of flexibility and some kinds of productivity against data on childrens first uses of their first-acquired verbs. Eight mothers recorded their childrens first 10 uses of 34 early acquired verbs, if those verbs were produced within the window of the study. The children were between 16 and 20 months when the study began (depending on when the children started to produce verbs), were followed for between 3 and 12 months, and produced between 13 and 31 of the target verbs. These diary records provided the basis for a description of the pragmatic, semantic, and syntactic properties of early verb use. The data revealed that within this early, initial period of verb use, children use their verbs both to command and describe, they use their verbs in reference to a variety of appropriate actions enacted by variety of actors and with a variety of affected objects, and they use their verbs in a variety of syntactic structures. All 8 children displayed semantic and grammatical flexibility before 24 months of age. These findings are more consistent with a model of the language-learning child as an avid generalizer than as a conservative language user. Childrens early verb use suggests abilities and inclinations to abstract from experience that may indeed begin in infancy.

Non-word repetition assesses phonological memory and is related to vocabulary development in 20- to 24-month-olds*

Two studies test the hypotheses that individual differences in phonological memory among children younger than two years can be assessed using a non-word repetition task (NWR) and that these differences are related to the childrens rates of vocabulary development. NWR accuracy, real word repetition accuracy and productive vocabulary were assessed in 15 children between 1 ; 9 and 2 ; 0 in Study 1 and in 21 children between 1 ; 8 and 2 ; 0 in Study 2. In both studies, NWR accuracy was significantly related to vocabulary percentile and, furthermore, uniquely accounted for a substantial portion of the variance in vocabulary when real word repetition accuracy was held constant. The findings establish NWR as a valid measure of phonological memory in very young children, and they open the door for further studies of the role of phonological memory in early word learning.

Relations among language exposure, phonological memory, and language development in Spanish-English bilingually developing 2-year-olds.

The relation of phonological memory to language experience and development was investigated in 41 Spanish-English bilingual first language learners. The childrens relative exposure to English and Spanish and their phonological memory for English- and Spanish-like nonwords were assessed at 22 months of age, and their productive vocabulary and grammar in both languages were assessed at 25 months of age. Phonological memory for English-like nonwords was highly correlated with that for Spanish-like nonwords, and each was related to vocabulary and grammar in both languages, suggesting a language-general component to phonological memory skill. In addition, there was evidence of language-specific benefits of language exposure to phonological memory skill and of language-specific benefits of phonological memory skill to language development.

Input and Language Development in Bilingually Developing Children

Language skills in young bilingual children are highly varied as a result of the variability in their language experiences, making it difficult for speech-language pathologists to differentiate language disorder from language difference in bilingual children. Understanding the sources of variability in bilingual contexts and the resulting variability in childrens skills will help improve language assessment practices by speech-language pathologists. In this article, we review literature on bilingual first language development for children under 5 years of age. We describe the rate of development in single and total language growth, we describe effects of quantity of input and quality of input on growth, and we describe effects of family composition on language input and language growth in bilingual children. We provide recommendations for language assessment of young bilingual children and consider implications for optimizing childrens dual language development.

The Cambridge Handbook of Environment in Human Development: Measurement and Model Building in Studying the Influence of Socioeconomic Status on Child Development

The process of child development is shaped by experience, and children who live in dif-ferent socioeconomic strata have difference experiences. Thus, it should not be surpris-ing that socioeconomic status (SES) is a pervasive predictor of child development. Children from higher SES families reliably fare better than children from lower SES families on a wide range of developmen-tal outcomes from infancy to adulthood. Although some of the predictive power of SES may derive from its correlation with properties that are genetically transmitted from parents to their children (Rowe & Rodgers, 1997), a substantial literature argues that SES indexes properties of children’s environments that affect development. Recent reviews of this substantial litera-ture argue also that the processes by which SES exerts its well-attested effects are not adequately understood (Bradley & Corwyn, 2002; Bornstein & Bradley, 2003; Conger & Donnellan, 2007; National Research Council and Institute of Medicine, 2000). Progress in understanding the mecha-nisms of SES infl uence requires measures that capture what about SES is relevant to children’s experience and models that cap-ture how SES exerts its infl uence. The ques-tions of how to measure SES and to model its infl uence are the topics of this chapter. In the sections that follow, we lay out the issues involved and illustrate the approaches that have been taken with selected research examples.