September 2015 Research Review: The Words Children Hear


This post was co-written by Erica Zippert and Dr. Betsy Diamant-Cohen 


This month’s article describes a research study about talking vs. reading picture books to children. “The Words Children Hear: Picture Books and the Statistic for Language Learning” by Jessica L. Montag, Michael N Jones, and Linda B. Smith is about the quality of parents’ language to their children and how this language differs from the quality of text in picture books.

It is imperative for children’s language development that they receive quality verbal input from their parents.  Research indicates that

talk directed to the child – rather than adult-adult or background talk — is the core data on which early language learning depends (e.g. Weisleder & Fernald, 2014).”

  These conversations are called child-directed speech, or talk directed to the child. The quality of parents’ talk to their children (or the variety of words spoken, called lexical diversity) has been shown to make the biggest difference.  Hart & Risley’s Meaningful Differences in the Everyday Experiences of Young American Children is often cited as the study that demonstrates the importance of parents speaking to their children to build vocabulary. That and other studies “Point to diversity in parents’ talk as a critical predictor of the outcome of language learning (Hart & Risley, 1995; Hoff, 2003; Hoff & Naigles, 2002; Huttenlocher, Waterfall, Vasilyeva, Vevea, & Hedges, 2010; Pan, Rowe, Singer & Snow, 2005; Rowe, 2012; Weizman & Snow, 2001). 

One context in which parents talk to their children is during storybook reading. Obviously infants cannot read; however, as librarians, we often suggest that parents can begin reading picture books to their children soon after they are born!  And in fact, many parents report doing so at home at least once a day! (Young et al., 1998).  Parents can read the text to the child word-for-word, or talk more generally about the storyline. Book reading can amount to a significant percentage of the talk children hear from their parents. (Deckner et al., 2006; Dickinson, Griffith, Golinkoff, & Hirsh-Pasek, 2012; Fletcher, Cross, Tanney, Schneider, & Finch, 2008; Mol, Bus, de Jong, & Smeets, 2008; Ninio & Bruner, 1978; Whitehurst et al., 1988).

It is likely that written language is of higher quality than spoken language (Hayes & Ahrens, 1988). Conversations among adults have been shown to be of lower lexical diversity than actual text geared towards adults (i.e., newspapers and adult fiction and non-fiction; Hayes & Ahrens, 1988).  It is not known, however, whether child-directed speech outside of book reading is as rich and diverse with words as compared to the text in children’s storybooks.  The study mentioned in this article aimed to test this idea.

Researchers used the following methods to conduct their study:

  1. Select a representative sample of current children’s books.  Researchers first gathered 100 children’s picture books (amounting to 68,103 total words) that parents could read to their children by examining lists of “librarian-recommended picture books, best sellers, and circulation statistics from the Infant and PreK sections” of an Indiana Public Library (the list of books can be found in the research article).

    2.  Gather a representative sample of child-directed speech.  Researchers chose transcripts of American English-speaking families with children aged 0-60 months to match the suggested age range of the books selected.  Transcripts were gathered from a large language database called CHILDES (Child Language Database Exchange Program), developed by Brian MacWhinney in 2000. This language bank serves a central role in providing information about language development, and providing data upon which many language and literacy studies are based.  The researchers made sure that the text and the parent language matched in terms of length and topic.

When researchers made comparisons between the combined samples of book text and parent talk respectively, they found that the samples of text from the picture books were substantially higher in lexical diversity than the parent speech by almost 2 times!   While single conversations and storybooks did not seem to have substantially diverse language (due to the fact that ideas and words in individual conversations and books focus on one topic and repeat), large samples of text from multiple books amounted to much more diverse language than did large amounts of parent speech outside of book reading.

The researchers suggest that the reason there is more varied language in storybooks is that typical conversations do not transcend the here and now, while storybooks are limitless in terms of the subjects covered. “The primary reason that book reading to infants results in a greater diversity of words in language input appears to be that different books sample the words in the language more broadly than do different conversations.”As an example, think about the conversations you have in the mornings. You may be talking about what you will have breakfast or what you will do that day, and this may not vary that much from day-to-day.  In contrast, storybooks about the same topics of breakfast could range from cereal to pork buns, to huevos rancheros, depending upon the origin of the family in the story.  “Thus, shared book reading, which often begins in infancy, creates a learning environment in which infants and children are exposed to words that they would never have encountered via speech alone.”  Therefore, infants who are read to by their parents on a regular basis are exposed to a greater variety of words and topics by their parents, and thus develop better language skills.

Bigger picture: This study helps us understand why it is so important for librarians to encourage families not only to visit the library once, but to continue coming back to borrow different books to read, to ultimately enrich the variety of the language children hear every day.


This article:

Montag, Jessica L. ,Michael N. Jones, and Linda B. Smith. (2015). The Words Children Hear: Picture Books and the Statistics for Language Learning. Psychological Science, 1-8. Psychological Science OnlineFirst, published on August 4, 2015 as doi: 10.1177/0956797615594361 


Please share your thoughts on this article with us below


Resources cited in the article:

Deckner, D. F., Adamson, L. B., & Bakeman, R. (2006). Child and maternal contributions to shared reading: Effects on language and literacy development. Journal of Applied Developmental Psychology, 27, 31–41.

Dickinson, D. K., Griffith, J. A., Golinkoff, R. M., & Hirsh- Pasek, K. (2012). How reading books fosters language development around the world. Child Development Research, 2012, Article 602807. Retrieved from http://

Fletcher, K. L., Cross, J. R., Tanney, A. L., Schneider, M., & Finch, W. H. (2008). Predicting language development in children at risk: The effects of quality and frequency of caregiver reading. Early Education and Development, 19, 89–111.

Hart, B., & Risley, T. R. (1995). Meaningful differences in the everyday experiences of young American children. Baltimore, MD: Brookes.

Hayes, D. P., & Ahrens, M. G. (1988). Vocabulary simplification for children: A special case of ‘motherese’? Journal of Child Language, 15, 395–410.

Hoff, E. (2003). The specificity of environmental influence: Socioeconomic status affects early vocabulary development via maternal speech. Child Development, 74, 1368–1378.

Hoff, E., & Naigles, L. (2002). How children use input to acquire a lexicon. Child Development, 73, 418–433.

Huttenlocher, J., Waterfall, H., Vasilyeva, M., Vevea, J., & Hedges, L. V. (2010). Sources of variability in children’s language growth. Cognitive Psychology, 61, 343–365.

Mol, S. E., Bus, A. G., de Jong, M. T., & Smeets, D. J. (2008). Added value of dialogic parent–child book readings: A meta-analysis. Early Education and Development, 19, 7–26.

Ninio, A., & Bruner, J. (1978). The achievement and anteced- ents of labelling. Journal of Child Language, 5, 1–15.

Pan, B. A., Rowe, M. L., Singer, J. D., & Snow, C. E. (2005). Maternal correlates of growth in toddler vocabulary produc- tion in low-income families. Child Development, 76, 763–782.

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.

Sénéchal, M., & LeFevre, J. A. (2002). Parental involvement in the development of children’s reading skill: A five-year lon- gitudinal study. Child Development, 73, 445–460.

Weisleder, A., & Fernald, A. (2014). Talking to children mat- ters: Early language experience strengthens processing and builds vocabulary. Psychological Science, 24, 2143– 2152.

Weizman, Z. O., & Snow, C. E. (2001). Lexical output as related to children’s vocabulary acquisition: Effects of sophisti- cated exposure and support for meaning. Developmental Psychology, 37, 265–279.

Whitehurst, G. J., Falco, F. L., Lonigan, C. J., Fischel, J. E., DeBaryshe, B. D., Valdez-Menchaca, M. C., & Caulfield, M. (1988). Accelerating language development through pic- ture book reading. Developmental Psychology, 24, 552–559.

Young, K. T., Davis, K., Schoen, C., & Parker, S. (1998). Listening to parents: A national survey of parents with young children. Archives of Pediatrics & Adolescent Medicine, 152, 255–262.



About Dr. Betsy Diamant-Cohen

A renowned national speaker and accomplished author, Dr. Betsy Diamant-Cohen is best known as the creator of Mother Goose on the Loose, an award-winning early literacy program. Her charismatic presentations always include an easily-understandable combination of research and practice. Recognized by the ASCLA Leadership and Professional Achievement Award for “revolutionizing the way librarians work with children from birth to age 3” and the 2018 Vattemare Award for Creativity in Libraries, Betsy’s passion is for helping children and the adults in their lives be the best they can be while sparking a love of reading.