Beyond the 30-Million-Word Gap: Children’s Conversational Exposure Is Associated With Language-Related Brain Function

Abstract

Children's early language exposure impacts their later linguistic skills, cognitive abilities, and academic achievement, and large disparities in language exposure are associated with family socioeconomic status (SES). However, there is little evidence about the neural mechanisms underlying the relation between language experience and linguistic and cognitive development. Here, language experience was measured from home audio recordings of 36 SES-diverse 4- to 6-year-old children. During a story-listening functional MRI task, children who had experienced more conversational turns with adults-independently of SES, IQ, and adult-child utterances alone-exhibited greater left inferior frontal (Broca's area) activation, which significantly explained the relation between children's language exposure and verbal skill. This is the first evidence directly relating children's language environments with neural language processing, specifying both an environmental and a neural mechanism underlying SES disparities in children's language skills. Furthermore, results suggest that conversational experience impacts neural language processing over and above SES or the sheer quantity of words heard.

Language Matters: Denying the Existence of the 30‐Million‐Word Gap Has Serious Consequences

“…Thus, Romeo et al. (), Hutton et al. (), and numerous behavioral studies (e.g., Cartmill et al., ; Malin et al., ) find that language quality and reading quality are contributors to children's brain development and language growth.…”

“…Indeed, language input that meaningfully builds on what children are doing in the moment, is rooted in shared attention, and models the use of syntax by using recasts and expansions of their utterances best facilitates language learning (e.g., Harris, Golinkoff, & Hirsh-Pasek, 2010;Malin, Cabrera, & Rowe, 2014;McGillion et al, 2017). As countless studies have shown, back-and-forth conversations that are both temporally and topically contingent on children's contribution, are the fuel that prime the learning of language (Goldin-Meadow et al, 2014;Reed, Hirsh-Pasek, & Golinkoff, 2017;Romeo et al, 2018;Tamis-LeMonda, Kuchirko, & Song, 2014). Second, the social-cognitive demands of overheard speech likewise exceed those for child-directed speech in that children have to infer others' interests and intentions, making sense of third-party interactions rather than one-on-one exchanges.…”

“…These components of "dialogic reading" (Whitehurst et al, 1988) were related to differences in brain activation in Broca's area. Thus, Romeo et al (2018), Hutton et al (2017), and numerous behavioral studies (e.g., Cartmill et al, 2013;Malin et al, 2014) find that language quality and reading quality are contributors to children's brain development and language growth. In this regard, SSM report on the extensive personal stories told in working-class African American families to their children, certainly valuable exchanges for children's later vocabulary development (Sperry & Sperry, 1996, 2000.…”

Socioeconomic Inequality and the Developing Brain: Spotlight on Language and Executive Function

“…Echoing these behavioral findings, in a recent study using fMRI, less advantaged parents had fewer conversational exchanges with their 4‐ to 6‐year‐olds than more advantaged parents. In turn, children who experienced fewer conversational exchanges had reduced activation in left inferior frontal regions during language processing (Romeo et al., ).…”

What do bilingual infants actually hear? Evaluating measures of language input to bilingual‐learning 10‐month‐olds

“…For example, the amount of infant-directed speech and turn-taking that children experience predicts their speech and language development (e.g. Ramírez-Esparza, García-Sierra, & Kuhl, 2014;Romeo et al, 2018). Another source of variability is the number of languages that they hear.…”