The Child and Family Research Section (CFRS) investigates dispositional, experiential, and environmental factors that contribute to physical, mental, emotional, and social development in human beings during the early years of the life course. Our overall goals are to describe, analyze, and assess the capabilities and proclivities of developing children, including their genetic characteristics, physiological functioning, perceptual and cognitive abilities, and emotional, social, and interactional styles as well as the nature and consequences for children and parents of family development and children’s exposure to and interactions with the inanimate environment. Project designs are longitudinal, cross-sectional, and cross-cultural. Sociodemographic comparisons include family socioeconomic status, maternal age and employment status, and child parity and daycare experience. Study sites include Argentina, Australia, Belgium, Brazil, Cameroon, Canada, England, France, Israel, Italy, Japan, Kenya, and Korea as well as the United States; the section pursues cross-cultural as well as intra-cultural comparisons of human development.

Parenting and Child Development
Bornstein, Suwalsky, Hahn, Haynes, Hendricks, Painter
Socioeconomic status (SES) is conceived of as a multidimensional construct that is indexed by quantitative factors associated with parents’ educational achievement, occupational status, and financial income. In a multilevel study of European American families of diverse SES, we used structural equation modeling to explore direct and indirect relations of SES for multiple indexes of maternal parenting and multiple indicators of infant development. We evaluated the predictive validity of SES as a composite as well as its several components alone. Although each component of SES predicted some aspects of maternal and infant behavior, maternal education proved the most robust unique predictor of SES effects, separate too from maternal intelligence and personality.

In a separate study of parenting effects on child language, we obtained data on children’s language through biweekly interviews with mothers. From these interviews, we calculated the timing of language milestones in children (e.g., 50 words in productive language, combinatorial speech). To analyze the effects of maternal verbal responsiveness on the timing of language achievements, we used Events History Analysis, a statistical approach that is suited to addressing questions of whether and by how much predictors affect the timing of events. First words in production, 50 words in receptive language, and maternal responsiveness at nine and 13 months were each significant predictors of the timing of 50 words in production. The relation between earlier responsiveness and the timing of 50 words is mediated by intervening linguistic competencies as well as by mothers’ later responsiveness. In support of this conclusion, our findings demonstrate that nine-month responsiveness predicted the timing of 50 words in receptive language along with the timing of first words in production and 13-month responsiveness. In turn, these mediators predicted when children acquired 50 words in their productive lexicons. In contrast, responsiveness at 13 months contributed unique variance to the timing of 50 words in production over and above the timing of first words in production, the timing of 50 words in receptive language, and responsiveness at nine months. With respect to the timing of children’s achievement of combinatorial speech, respon-siveness at nine months contributed unique variance, above the contribution of 50 words in receptive language, but did not contribute unique variance above the timing of first words in production or responsiveness at 13 months. Responsiveness at 13 months contributed unique variance to the timing of combinatorial speech over and above the timing of first words in production, the timing of 50 words in receptive language, and responsiveness at nine months. Again, responsiveness at nine months improved model fit through its relation with first words in production and responsiveness at 13 months, both of which uniquely predicted when children first combine words. Children with verbally responsive mothers achieve the vocabulary spurt and combine words into simple sentences sooner in development than children with less responsive mothers. Predictive associations between responsiveness and the timing of children’s language milestone are more robust at 13 than at nine months, and they matter above the contributions of children’s earlier language abilities. The best-fitting model, however, is one that includes both children’s and mothers’ contributions to second-year language gains. That is, a child who produces first words sooner in development, coupled with a verbally responsive mother, is at a strong advantage for precocious achievement of key language milestones.

Family and Child Acculturation in Modern America
Bornstein; in collaboration with Cote
One study examined similarities and differences in mothers’ and infants’ activities and interactions among Japanese American and South American immigrant dyads when infants were five months of age. Few relations between maternal acculturation level or individualism/collectivism and maternal parenting or infant behaviors emerged in either group. However, we observed group differences in mothers’ and infants’ behaviors, indicating that mothers’ culture of origin continues to influence parenting behavior in the two acculturating groups. We next examined cultural generality and specificity in relations among and between mothers’ and infants’ behaviors. Few relations among mothers’ behaviors emerged, except for that between mothers’ social behavior and other types of maternal behavior, which appear to reflect a common collectivist orientation of the two cultural groups. Few relations among infants’ behaviors emerged, suggesting independence and plasticity in infant behavioral organization. Several expected relations between mothers’ and infants’ behaviors also emerged, pointing to some universal characteristics in mother-infant interactions.

A follow-up longitudinal study evaluated differences, continuity, and stability in cultural cognitions (acculturation, individualism, collectivism) and parenting cognitions (attributions, self-perceptions, knowledge) in the same samples of Japanese American and South American acculturating mothers when their children were five and 20 months of age. South American immigrant mothers were more collectivist than Japanese American immigrant mothers. Cultural group and attribution differences emerged for mothers’ attributions in successful situations, whereas child age and attribution differences emerged for attributions in unsuccessful situations. Japanese American immigrant mothers’ feelings of competence increased over time. South American immigrant mothers were more satisfied with the parenting role than Japanese immigrant mothers. Mothers’ knowledge of parenting increased over time in both groups. Mothers’ cultural cognitions were largely stable, and Japanese American mothers’ parenting cognitions were highly stable. Further analysis evaluated prediction and coherence among mothers’ cultural and parenting cognitions. Mothers’ cultural cognitions at five months predicted some parenting cognitions at 20 months, particularly among Japanese American immigrant mothers. At five and 20 months, coherence among mothers’ attributions was found for both cultural groups and among Japanese American mothers’ perceptions of parenting. Even though we found a few relations across types of parenting cognitions, these domains of parenting cognitions appeared to be relatively independent. The study provides insight into the nature and structure of parenting cognitions in two groups acculturating to the United States.

Infant and Child Development
Bornstein, Suwalsky, Hahn, Haynes, Hendricks, Painter
We conducted several studies geared to understanding physiology, perception, and cognition in infants leading to language development. First, we measured and quantified fetal cardiac function at 24, 30, and 36 weeks’ gestation in terms of heart rate, variability, and episodic accelerations and later evaluated children’s language capacity at 27 months. Thirty- and 36-week-old fetuses that displayed greater heart-rate variability and more episodic accelerations and fetuses that exhibited a more precipitous increase in heart-rate variability and acceleration over gestation achieved higher levels of language competence. Cardiac patterning during gestation appears to reflect an underlying neural substrate that persists through early childhood; individual variation in rate of development could be stable, or efficient cardiac function could positively influence the underlying neural substrate to enhance cognitive performance.

We next investigated infants’ categorization of nonverbal objects based on static versus dynamic attributes of stimuli in four experiments: six-month-olds categorized static color images of animals and vehicles; six-month-olds categorized dynamic point-light displays showing only motions of the same animals and vehicles; six- and nine-month-olds were tested in a habituation-transfer paradigm, with half of the infants at each age habituating to static images and tested with dynamic point-light displays and the other half to dynamic point-light displays and tested with static images. Six-month-olds did not transfer. Only nine-month-olds who were habituated to dynamic displays showed evidence of category transfer to static images.

Further study compared naturalistic samples of four features of language in two-year-olds in the home in three contrasting situations: the child observed playing by her- or himself with mother nearby, the child and mother observed in direct play interaction, and the child and mother unobserved at a time the mother judged would provide a sample of the child’s “optimal” language. Children produced more utterances and word roots and expressed themselves in longer utterances when in interaction than when playing “alone,” but children’s utterances, word roots, and utterance length were greatest in the “optimal” language production situation. Girls used more word roots and spoke with longer mean length of utterance (especially in the “optimal” language situation) than boys. Despite mean level differences, children maintained their rank orders across the three situations in use of word roots and in utterance length. These findings have implications for understanding children’s language and the validity of sampling child language.

In a further, methodological examination of child language, children participated in three longitudinal studies of general language performance (cumulatively from one year, one month to six years, 10 months). Data were drawn from maternal questionnaires, maternal interviews, experimenter assessments, and teacher reports. We assessed general language performance at each age and the stability of individual differences across age in girls and boys separately and together. Across age, including the important transition from preschool to school, across multiple tests at each age, and across multiple reporters, children showed moderate to strong stability of individual differences; girls and boys alike were stable. In the second through fifth years, but not before or after, girls consistently outperformed boys in general language ability.