Predicting variation in the timing of language milestones in the second year: an events history approach

Abstract

In a longitudinal investigation of 40 child–mother dyads, we examined prediction from three indexes of children's own language: (1) vocal imitations, (2) first spontaneous words in production, and (3) receptive language starting at 0;9, and their mothers' verbal responsiveness at 0;9 and 1;1, to the developmental onset of three significant language milestones of the second year: (1) 50 words in productive language, (2) combinatorial speech, and (3) the use of language to express a memory. In these analyses, we utilized EVENTS HISTORY ANALYSIS, a statistical technique well suited to questions concerning when in development certain events begin and the extent to which predictors influence the timing of those events. The timing of children's first words in production, the timing of their achievement of 50 words in receptive language, and maternal responsiveness at 1;1 each contributed uniquely to variation in the timing of the three language milestones. When child and mother factors were considered together, the onset of the three language milestones differed by as much as 0;5 months for children in the lower and upper 10th percentiles of the predictor variables. The present findings contribute to generating and testing specific models about child and mother factors thought to explain variation in key aspects of children's second-year language development.

Maternal Responsiveness and Children's Achievement of Language Milestones

“…To receive credit for expressing a "word," children had to (1) approximate the phonetic form of the word (e.g., "ehh" for bottle was not credited, whereas "bot" for bottle was), (2) use the phonetic form in a consistent way with a recognizable meaning, (3) express the word spontaneously, and (4) use the word across multiple contexts. Thus, words used in restricted contexts were noted but were not counted in analyses (see Bates et al, 1988;Goodwyn & Acredolo, 1993;Tamis-LeMonda & Bornstein, 1994;Tamis-LeMonda et al, 1998;Vihman & McCune, 1994). Thus, relatively conservative criteria were adopted for crediting different language achievements.…”

“…More recently, by using Events-History Analysis, it has been shown that mothers' overall responsiveness at 13 months predicted the timing of several secondyear language milestones (Tamis- LeMonda et al, 1998). Specifically, children with more responsive mothers were found to achieve the vocabulary spurt and combinatorial speech, and use language to talk about the past sooner in development than were children with less responsive mothers.…”

Supporting Early Vocabulary Development: What Sort of Responsiveness Matters?

“…Subsequent research has produced a more nuanced picture of maternal directiveness and one that does not necessarily suggest a negative impact on development [2], [32], [38]. Building on these observations, several studies have since continued to explore different dimensions of responsiveness, with a focus on considering the pragmatic functions of caregivers' speech with their infants from 9 mo [44], [45] through the first year [2] and beyond [25].…”

Language Experience and Language Milestones During Early Childhood

“…This is another property of child-directed speech that varies as a function of maternal education and contributes to the SES-related differences in children's vocabularies (Hoff, 2003). It also helps, particularly for children under 18 months, if the timing of speech is responsive to child verbalizations and if the content of the speech is related to the child's focus of attention (Tamis-LeMonda, Bornstein, Kahana-Kalman, Baumwell, & Cyphers, 1998;Tomasello & Todd, 1983). In older children, vocabulary growth is predicted by the informativeness of the context in which new words are presented.…”

“…Children whose mothers are more responsive to their early attempts to communicate do acquire language more rapidly than do children with less responsive mothers. This is not just a general benefit of responsive caregiving -the effect of responsivity to verbalization is specific to language development (Tamis-LeMonda & Bornstein, 1994;Tamis-LeMonda et al, 1998).…”