A longitudinal investigation of the role of quantity and quality of child-directed speech in vocabulary development.

“While it is acknowledged that some of this variability is likely due to genetics (see Stromswold, 2001, for a review), environmental factors also play an integral role (see Hoff, 2006, for a review).”

“When SES is controlled, children’s language exposure remains strongly associated with variation in their language abilities (Rowe, 2012; Weisleder & Fernald, 2013), and differences in exposure partially or fully explain the SES-related gap in language skills (Hoff, 2006).”

“…Bruner, 1983), as infants and caregivers “converse” using gaze, gestures, vocalizations, and facial expressions; it then becomes increasingly symbol-infused and decontextualized as children become increasingly sophisticated language users (Adamson, Bakeman, Deckner, & Nelson, 2014; Rowe, 2012).”

“Rowe (2012) showed that parents’ vocabulary diversity as reported at 30 months, and not quantity of words per se, predicted children’s vocabulary at 42 months.”

“For example, in a socioeconomically diverse sample of families from the greater Chicago area, Rowe (2012) found that parent education (a core component of SES) was significantly, positively correlated with the diversity and sophistication of parents ’ vocabulary and with the number of pretend…”

“In a more recent study Rowe (2012) reported that the quality of speech – as measured by the sophistication of the vocabulary used by caregivers, while controlling for SES – predicts later language learning.”

“Rowe (2012) essentially validated this perspective in a longitudinal study on vocabulary development.”

“Type and token counts and type-token ratios are widely used in the study of language development, and individual differences in type-token ratios in the language-learning environment are predictive of vocabulary development (Huttenlocher et al., 2010; Pan et al., 2005; Rowe, 2012; Weizman & Snow, 2001).”

“7 Measures of quality included parents ’ use of diverse vocabulary, rare words, and decontextualized language (e.g., narratives and explanation).”

“…development even when controlling for SES (e.g., Hoff & Naigles, 2002; Rowe, 2008; Weisleder & Fernald, 2013; see also Hirsh-Pasek et al., 2015; Rowe, 2012; Rowe & Goldin-Meadow, 2009; Cartmill et al., 2013 for additional considerations; and Hodson, 2014; Baker-Henningham & L opez Boo, 2010…”

“There is evidence that mothers may exhibit less responsive parenting toward male versus female children(30) and that parenting behavior may have a greater impact on children’s language skills at certain developmental stages of language.(31)”

“…further supports the idea that qualitative aspects of children’s early language experience, as opposed to sheer quantitative aspects, may be the largest influence on children’s language development (Zimmerman et al., 2009; Rowe, 2012; Roseberry et al., 2014; Hirsh-Pasek et al., 2015).”

“…shows that early differences in vocabulary growth among otherwise typically developing children are strongly related to differences in their language learning environments (Hart & Risley, 1999; Hoff, 2013; Newman et al., 2016; Ramirez- Esparza et al., 2014; Rowe, 2012; Weisleder & Fernald, 2013).”

“Previous research shows that some aspects of parental input may relate more to child language development at different developmental stages than others (40), and future studies should investigate the importance of parentese and other social aspects of parental speech at later ages.”

“A growing body of research has identified substantial individual differences in the quality and quantity of caregiver speech and corresponding individual differences in children’s speech (Huttenlocher et al. 1991, Hart & Risley 1995, Hoff 2003, Rowe 2012).”

“Furthermore, language quality also varies as a function of SES, such that higher SES parents use greater variety of words and more complex syntactical structure (Rowe, 2012).”

“…might be in part due to their linguistic complexity, aspects of language that are known to positively predict children’s language and literacy outcomes (e.g., Hart & Risley, 1995; Huttenlocher, Haight, Bryk, Seltzer, & Lyons, 1991; Huttenlocher, Vasilyeva, Cymerman, & Levine, 2002; Rowe, 2012).”

“The results here confirm those of Rowe (2012), which suggest that while input quantity is important during the very early years of language learning (up to ~30 months), thereafter it is crucial for the child to hear a range of utterances and vocabulary items.”

“Keywords: touchscreen, tablet, infant, toddler, developmental milestones, fine motor Frontiers in Psychology | www.frontiersin.org 1 August 2016 | Volume 7 | Article 1108”

“Rowe (2012) identified conversations about personal experiences in the past and future (narrative talk) as pervasive in children’s everyday lives and as especially important for preschool children’s complex language skills.”

“Outcome Variables Each play session was transcribed by a research assistant and coded for the variables of interest: (1) number of adult words, (2) number of content-specific words, (3) number of child vocalizations, (4) number of conversational turns, and (5) number of parent responses per minute.”

“, 2012) as well as the now well-established literature that reports that monolingual language development is linked to the characteristics of language input children receive in their everyday lives (e.g., Hart & Risley, 1995, 1999; Hurtado et al., 2008; Huttenlocher et al., 1991; Ram ırez-Esparza et al., 2014; Rowe, 2…”

“…structures than contextualized talk, and is a significant predictor of children’s later vocabulary knowledge and narrative skills, even when controlling for input quantity or contextualized talk (Beals, 2001; Katz, 2001; Rowe, 2012; Demir, Rowe, Heller, Goldin-Meadow, & Levine, 2015).”

“In addition to the quantity of language input, the quality of language input is often an even stronger predictor of children ’ s language skills (Hirsh-Pasek et al., 2015; Merz et al., 2015; Pace et al., 2017; Ram (cid:1) ı rez-Esparza, Garc (cid:1) ı a-Sierra, & Kuhl, 2014; Rowe, 2012; Weisleder & Fernald, 2013).”

“A recent study examined whether parents change over time in their use of decontextualized language and whether decontextualized language input related to children’s gains in receptive vocabulary development.(16) The study also asked whether relations between decontextualized language and child vocabulary remained when…”

“For example, several studies have documented considerable variability in the amount of speech directed at children by caregivers during the course of a typical day (Hoff 2003; Rowe 2012).”

“Discussion Previous studies indicate that parent decontextualized language––talk about the there-andthen––predicts later child language (Rowe, 2012, Tabors, Roach & Snow, 2001).”

“2006) in typical development that remained strong even after controlling for parental SES (Rowe 2012; Weisleder & Fernald 2013).”

“The influence of socioeconomic status might be mediated through aspects of parent–child communication (Hoff 2003; Rowe 2012) or through other differences in the environments of children from low- and high-income families (Evans 2004, 2006; Ferguson et al.”

“53–55 These features have not been directly examined in studies of input and bilingual development, however.”

“…extended this work and examined the properties of early language environment and their relationships with developmental outcomes (Greenwood, Thiemann-Bourque, Walker, Buzhardt, & Gilkerson, 2011; Hoff & Naigles, 2002; Romeo et al., 2018; Rowe, 2012; Weisleder & Fernald, 2013; Weizman & Snow, 2001).”

“…finding that children who receive greater amounts of input, more responsive social interactions with caregivers, and more diverse input, demonstrate earlier and/or more complex language use (Gathercole & Hoff, 2007; Rowe & GoldinMeadow, 2009; Rowe, 2012; Tamis-LeMonda, Kuchirko, & Song, 2014).”

“…vocabulary size and early school achievement (Dickinson, Golinkoff, & Hirsh-Pasek, 2010; Hart & Risley, 1995; Hoff, 2003; Huttenlocher et al., 2010; Rowe, 2012; Walker, Greenwood, Hart, & Carta, 1994) and are also highly associated with the socio-economic standing of the families (Hoff, 2003;…”

“12166 Rowe, M. L. (2012). A longitudinal investigation of the role of quantity and quality of child-directed speech in vocabulary development. Child Development, 83, 1762–1774. http://dx.doi.org/10.1111/j.1467-8624 .2012.01805.x Saint-Georges, C., Chetouani, M., Cassel, R., Apicella, F., Mahdhaoui, A., Muratori, F., .…”

“Importantly, what we know from our own research (e.g., Ramani 2012, 2014; Rowe 2012) and that of others (e.”

“…advancements in all-day recordings have confirmed that, on average, children in low-SES households are exposed to less complex and less varied speech than those in high-SES households (Fernald et al., 2013; Gilkerson et al., 2017; Huttenlocher et al., 2010; Pan et al., 2005; Rowe, 2012).”

“Language input has substantial impact on language learning in children (e.g., Huttenlocher et al., 1991; Hart and Risley, 1995, 1999; Rowe, 2012; Ramírez-Esparza et al., 2014, 2017; for a review see Hoff, 2006), and various characteristics of that input have been associated with language learning outcomes.”

“, 1994; Hoff, 2006) and some of which are associated with quantitative properties of the language environment, such as quantity and diversity of child-directed conversation (e.g., Newman, Rowe, & Bernstein-Ratner, 2015; Rowe, 2012; Weisleder & Fernald, 2013).”

“While there are many reasons for the link between social disadvantage and language ability, evidence suggests that family background is associated with aspects of language input important in development, such as the amount of speech that children hear, lexical diversity, and conversational turn-taking, as well as pare…”

“There is evidence that input is a source of individual differences in language growth and a source of socioeconomic disparities in children’s language skills (e.g., Cartmill, Armstrong, Gleitman, GoldinMeadow, Medina, & Trueswell, 2013; Hart & Risley, 1995; Rowe, 2012).”

“2002; Rowe 2012).”

“…decontextualized topics is strongly associated with oral language skills at kindergarten entry (Demir, Rowe, Heller, Goldin-Meadow, & Levine, 2015; Dickinson & Tabors, 2001; Rowe, 2012; Snow, 1983, 1991) and later academic language abilities (Uccelli, Demir, Rowe, Levine, & Goldin-Meadow, 2017).”

“Language quality was measured using rate of unique words because of the importance of varied language for children’s vocabulary development (Hart & Risley, 1995; Rowe, 2012).”

“The quantity of child-directed speech (CDS) does not necessarily increase as children grow from toddlerhood into preschool age, but various other aspects of CDS do (Rowe 2012).”

“More recent research suggests that both the quantity and quality of language varies by SES and influences language development in children (Gilkerson et al., 2017; Hurtado et al., 2008; Romeo et al., 2018; Rowe, 2012; Weisleder and Fernald, 2013).”

“…the importance of early environments and interactions with trusted caregivers for the development of children’s cognitive, language and literacy, and social-emotional skills (Bradley et al., 1989; Rowe, 2012; Dieterich, Assel, Swank, Smith, & Landry, 2006; Cabrera, Karberg, Malin, & Aldoney, 2017).”

“Maternal diversity of vocabulary has generally been found to be predictive of children’s current as well as later language, especially in samples of low-income children (Hart and Risley, 1995; Pan, Rowe, Singer and Snow; 2005; Rowe, 2012).”

“Additionally, the quality of parental language input may be related to improved vocabulary skills in typically developing children (Rowe, 2012).”

“words (Rowe 2012).”

“about how adults can support children’s word learning (8), many effective techniques are not practiced widely.”

“However, by 30 months, parents’ use of diverse vocabulary and rare words, as compared to input quantity, was more strongly related to children’s vocabulary growth (Rowe, 2012).”

“Several researchers have now studied larger samples of families from more diverse backgrounds, confirming disparities among children in their early language experience that are related to several different aspects of vocabulary and language growth [Hoff, 2003, 2013; Huttenlocher, Waterfall, Vasilyeva, Vevea, & Hedges,…”

“…with the tendency for early language outcomes and outcome disparities to be most often discussed in terms of lexical knowledge (e.g., Bates et al., 1994; Huttenlocher, Haight, Bryk, Seltzer, & Lyons, 1991; Rowe, 2012; Shneidman, Arroyo, Levine, & Goldin-Meadow, 2013; Weisleder & Fernald, 2014).”

“Disparities in the diversity and complexity of linguistic inputs significantly contribute to smaller vocabularies and lower language skills among children with low-SES backgrounds (e.g., Hart & Risley, 1995; Hoff, 2003; Rowe, 2012).”

“These measures were better predictors of children’s later language than maternal total words (Hoff, 2003; Huttenlocher et al., 2010; Rowe, 2012; Rowe, Raudenbush, & Goldin-Meadow, 2012; Vernon-Feagans et al., 2013; Vernon-Feagans et al., 2008).”