Quantity and Quality: Individual Differences in Early Language Input and Relations to Later Child Vocabulary

• In Event: 3-142 - Children´s Language Ability: The Role of Type, Quantity, and Quality Of Parents’ Language Input.

Integrative Statement

Much research demonstrates the importance of early language input for later language ability (e.g., Hart & Risley, 1995; Tomasello & Farrar, 1986). However, there is debate on the relative roles of quantity and quality of language input (Cartmill et al., 2013; Hart & Risley, 1995; Hirsh-Pasek et al., 2015; Rowe, 2012). One finding is that the quality of the parent-child Communication Foundation, characterized by bouts of shared attention infused with symbols and fluid back-and-forth exchanges, is a stronger predictor of language outcomes one year later than the quantity of speech when children were age 2 (Hirsh-Pasek et al., 2015). Here, we use the data from Hirsh-Pasek et al. (2015) to test for individual differences in the relationship between quantity of language input and the quality of the communication foundation. Specifically, we look at how the relationship between these variables interact to predict children’s later language.

Sixty low-income participants, selected to represent a wide range of language abilities, were drawn from the NICHD-Study of Early Child Care and Youth Development. Quantity of language input (maternal words per minute; WPM) and quality of the Communication Foundation (CF; Adamson et al., 2016) were assessed at 24-months during the 3-box task, a semi-naturalistic interaction in which mother and child played for 15-minutes with a book and two toys. Children’s 36-month vocabulary was assessed using the Reynell Developmental Language Scales (Reynell, 1990).

Previous findings showed that WPM and CF independently relate to children’s language outcomes, though when examined simultaneously, only CF remains a significant predictor (Hirsh-Pasek et al., 2015). Here, we examined the interaction between WPM and CF. Not only was it significant (B=-.194, t(56)=-2.142, p=.037), but simple slopes testing showed that WPM was only a significant predictor of later language for children who experienced a poor quality communication foundation (B=.37, t(56)=2.43, p=.020).

These findings suggest that at age 2, the amount of language children hear may be important, but only for some children. Children who experience lower-quality language interaction may require more exposures to a word to effectively learn it. In contrast, children who experience higher-quality interaction may not need to hear a word as often, making the overall amount of language input they hear less critical. These apparently different pathways to successful language acquisition suggest that the debate about quantity versus quality may not capture the whole picture. Children are immersed in language environments that variety in both quantity and quality of talk. We must consider how different permutations of these factors work together. By understanding what works best for whom and when, we can build interventions tailored to the individual and truly help all children succeed.

Authors

• Lillian Masek, Temple University
  Presenting Author

• Kathy Hirsh-Pasek, Temple University
  Non-Presenting Author

• Roberta Michnick Golinkoff, Univ of DE
  Non-Presenting Author