Marina Vasilyeva

Sources of Variability in Children’s Language Growth

The present longitudinal study examines the role of caregiver speech in language development, especially syntactic development, using 47 parent-child pairs of diverse SES background from 14 to 46 months. We assess the diversity (variety) of words and syntactic structures produced by caregivers and children. We use lagged correlations to examine language growth and its relation to caregiver speech. Results show substantial individual differences among children, and indicate that diversity of earlier caregiver speech significantly predicts corresponding diversity in later child speech. For vocabulary, earlier child speech also predicts later caregiver speech, suggesting mutual influence. However, for syntax, earlier child speech does not significantly predict later caregiver speech, suggesting a causal flow from caregiver to child. Finally, demographic factors, notably SES, are related to language growth, and are, at least partially, mediated by differences in caregiver speech, showing the pervasive influence of caregiver speech on language growth.

Socioeconomic Status Modifies the Sex Difference in Spatial Skill

We examined whether the male spatial advantage varies across children from different socioeconomic (SES) groups. In a longitudinal study, children were administered two spatial tasks requiring mental transformations and a syntax comprehension task in the fall and spring of second and third grades. Boys from middle-and high-SES backgrounds outperformed their female counterparts on both spatial tasks, whereas boys and girls from a low-SES group did not differ in their performance level on these tasks. As expected, no sex differences were found on the verbal comprehension task. Prior studies have generally been based on the assumption that the male spatial advantage reflects ability differences in the population as a whole. Our finding that the advantage is sensitive to variations in SES provides a challenge to this assumption, and has implications for a successful explanation of the sex-related difference in spatial skill.

The varieties of speech to young children.

This article examines caregiver speech to young children. The authors obtained several measures of the speech used to children during early language development (14-30 months). For all measures, they found substantial variation across individuals and subgroups. Speech patterns vary with caregiver education, and the differences are maintained over time. While there are distinct levels of complexity for different caregivers, there is a common pattern of increase across age within the range that characterizes each educational group. Thus, caregiver speech exhibits both long-standing patterns of linguistic behavior and adjustment for the interlocutor. This information about the variability of speech by individual caregivers provides a framework for systematic study of the role of input in language acquisition.

Emergence of Syntax: Commonalities and Differences across Children.

This paper presents the results of a longitudinal examination of syntactic skills, starting at the age of emergence of simple sentences and continuing through the emergence of complex sentences. We ask whether there is systematic variability among children from different socioeconomic backgrounds in the early stages of sentence production. The results suggest a different answer for simple versus complex sentences. We found a striking similarity across SES groups on the measures tapping early mastery of basic syntactic rules of simple sentences. At the same time, there was a significant difference between SES groups in the mastery of complex sentence structures. This difference emerged at the earliest stages of production of multi-clause sentences and persisted throughout the period of observation. The implications of these findings for the understanding of mechanisms of syntactic development are discussed.

Spatial Scaling in Young Children

This article examines the emergence of the ability to use a simple map to acquire information about distance in a larger space. It is commonly believed that scaling is a late achievement in childhood. The present study examined the origins of this ability by using the simplest of situations. In two experiments, we presented preschool children with a dot in a long thin rectangle, and asked them to use that representation to find an object in a corresponding location in a much larger sandbox. All 4-year-olds and a majority of 3-year-olds performed well on this task. We present a model that posits a simpler mechanism for scaling than that proposed in the existing literature.

Effects of Language Intervention on Syntactic Skill Levels in Preschoolers.

Questions concerning the role of input in the growth of syntactic skills have generated substantial debate within psychology and linguistics. The authors address these questions by investigating the effects of experimentally manipulated input on childrens skill with the passive voice. The study involved 72 four-year-olds who listened to stories containing either a high proportion of passive voice sentences or a high proportion of active voice sentences. Following 10 story sessions, childrens production and comprehension of passives were assessed. Intervention type affected performance--children who heard stories with passive sentences produced more passive constructions (and with fewer mistakes) and showed higher comprehension scores than children who heard stories with active sentences. Theoretical implications of these results for the understanding of the nature of syntactic skills and practical implications for the development of preschool materials are discussed.

Syntactic Priming in 3- and 4-Year-Old Children: Evidence for Abstract Representations of Transitive and Dative Forms.

The current studies used a syntactic priming paradigm with 3- and 4-year-old children. In Experiment 1, children were asked to describe a series of drawings depicting transitive and dative relations to establish baseline production levels. In Experiment 2, an experimenter described a similar series of drawings using one of two syntactic forms (i.e., active/passive for transitive; double-object/prepositional for dative). Children were then asked to describe pictures identical to those shown in the corresponding baseline procedure. In both transitive and dative conditions, 4-year-old children were more likely to use a particular syntactic form if it had been used by the experimenter. Three-year-old children did not show priming effects, but their production of transitive sentences was higher following transitive primes than in Experiment 1. In Experiment 3, an additional group of 3-year-olds participated in a procedure in which they repeated the experimenters sentences before describing the pictures. This procedure yielded significant priming effects for transitive and dative forms. These results indicate that very young children possess abstract syntactic representations, but that their access to these representations is sensitive to task demands.

The Relation between Teacher Input and Lexical Growth of Preschoolers.

The present study examined the growth of receptive lexical skills in preschoolers over an academic year in relation to teacher speech. The participating students were English language learners and their monolingual English-speaking peers from the same classrooms. The measures of teacher input included indicators of the amount of speech (total number of words), lexical richness (number of different word types), and structural complexity (number of words per utterance). These measures were based on a speech sample collected during a classroom observation. For English language learners, vocabulary growth was positively related to the total number of words produced by the teacher, but negatively related to the number of words per utterance. For monolingual speakers, vocabulary growth was positively related to the number of word types produced by the teacher. The findings underscore the importance of considering different aspects of verbal input for understanding individual variability in language growth of preschool students.

An Examination of Stereotype Threat Effects on Girls' Mathematics Performance

Stereotype threat has been proposed as 1 potential explanation for the gender difference in standardized mathematics test performance among high-performing students. At present, it is not entirely clear how susceptibility to stereotype threat develops, as empirical evidence for stereotype threat effects across the school years is inconsistent. In a series of 3 studies, with a total sample of 931 students, we investigated stereotype threat effects during childhood and adolescence. Three activation methods were used, ranging from implicit to explicit. Across studies, we found no evidence that the mathematics performance of school-age girls was impacted by stereotype threat. In 2 of the studies, there were gender differences on the mathematics assessment regardless of whether stereotype threat was activated. Potential reasons for these findings are discussed, including the possibility that stereotype threat effects only occur in very specific circumstances or that they are in fact occurring all the time. We also address the possibility that the literature regarding stereotype threat in children is subject to publication bias.

Early Development of Scaling Ability.

The map is a small-scaled version of the space it represents. It has been argued that children have difficulty interpreting maps because they do not understand scale relations. Recent research has shown that even preschoolers can solve problems that involve scaling in one dimension. This study examined whether early scaling ability extends to tasks involving two-dimensional maps and referent spaces of different sizes. Results showed that about 60% of the 4-year-olds and 90% of the 5-year-olds tested used distance information presented on a map to locate an object in a two-dimensional spatial layout. Children had more difficulties in solving mapping tasks with a larger referent space. This decrease in accuracy as a function of space size on the mapping task was greater than would have been expected on the basis of performance on a parallel nonmapping task. The results are discussed in terms of their implications for the mechanisms underlying early scaling ability.