Debating the 30 Million Word Gap


Let’s Stop Talking About the Thirty-Million Word Gap,” published June 1 on NPR Ed’s website, took a fresh look at what has become a familiar phrase. Citing two recent studies that attempt to quantify, with modern technology and larger sample sizes, the number of words heard by children of varying socio-economic levels, the article also addresses the “whole idea of a gap,” quoting criticism that views “the ‘word gap’concept as racially and culturally loaded in a way that ultimately hurts the children whom early intervention programs [are] ostensibly trying to help.”

The first study, “Mapping the Early Language Environment” (Gilkerson et al, American Journal of Speech-Language Pathology, May 2017) used “the Language Environment Analysis (LENA) System to generate estimates of (a) the number of adult words in the child’s environment, (b) the amount of caregiver-child interaction, and (c) the frequency of child vocal output.” It found that “Lower socioeconomic status (SES) children produced fewer vocalizations, engaged in fewer adult-child interactions, and were exposed to fewer daily adult words compared with their higher socioeconomic status peers, but within-group variability was high.” [emphasis added]

That last phrase highlights one of the ways Hart and Risley has been misinterpreted: overgeneralizing the findings as if they apply to all families in a particular SES status–which can lead to implicit blame of low-income families, and a failure to search for commonalities based on quality of language exposure rather than SES.

The second study, “Reexamining the Verbal Environments of Children From Different Socioeconomic Backgrounds,” (Sperry, Sperry and Miller, Child Development, April 30, 2018) addresses this issue directly, revealing “substantial variation in vocabulary environments within each socioeconomic stratum, and suggest[ing] that definitions of verbal environments that exclude multiple caregivers and bystander talk disproportionately underestimate the number of words to which low‐income children are exposed.”

However, a critique of the latter study, “Talking With Children Matters: Defending the 30 Million Word Gap,” (Hirsh-Pasek, et al, Brookings.edu, May 21, 2018), points out that without an upper-middle-class cohort for comparison, the disparity in the number of language interactions cannot be measured–and it is the disparity that leads to the relative disadvantage for children of all SES who have fewer reciprocal verbal interactions. In addition, the article points out that, while the Sperry study measures the number of words heard in the child’s environment, rather than “conversational turns,” it is the reciprocal nature of those “serve-and-return” interactions that supports not only language development but also secure attachment.

What do these alternative perspectives mean for Reach Out and Read? National Medical Director Perri Klass MD reminds us that there is a great deal of data to support the finding that disparities in early environment and parent-child interactions have an impact on child development, but that it is also true that many factors besides SES affect a child’s home environment and relational experiences. Our job always is to support parents, across all circumstances of SES and family situations, while remembering that poverty imposes additional stresses with which families must cope.

We know that it is very important to guard against any suggestion of blaming poor parents for the circumstances of poverty, and that we should never equate parenting in poverty with poor parenting. It’s useful and helpful to think about the complexities of early stimulation and a positive environment, and about the complexities of language and interaction and relational health–and that helping parents and children look at books together and talk about them fosters language interaction and “conversational: turn-taking, as well as enriched vocabulary. This should help us to work toward a better understanding of what works to support parents, and to help them use reading together and looking at picture books to help their children grow and develop.