Can we, as a society, influence the earliest years of a child’s life to prevent the academic achievement gap? New research on cognitive development suggests that we can.
Differences in language exposure are a key predictor of children’s later success, according to a 1995 landmark study by researchers Betty Hart and Todd Risley. But since then, we’ve learned that the back-and-forth interactions between adult caregivers and children — known as “conversational turns” — are even more critical than previously believed.
In other words, one of the most important things we can do to stimulate a child’s early brain development is also one of the simplest: talk.
In 2005, as much of the research on conversation was beginning, I joined LENA, a nonprofit focused on closing the early talk gap, often referred to as the “30 million word gap.”
We developed the first wearable technology to measure a child’s language environment, a sort of “talk pedometer,” which automatically measures both the number of words adults are speaking and the verbal interactions known as conversational turns.
Now, newly published research conducted by a team at Harvard and MIT has used LENA technology and functional magnetic resonance imaging techniques to gauge the degree to which talk and interaction are related to processing in the brain’s primary language center.
Children in the study, aged 4 to 6, completed a number of language assessments, and then listened to stories while their brain activity was measured.
The Harvard/MIT study generated two findings that are significant for parents and early childhood educators. First, although the amount of adult language and the frequency of child vocalizations are both correlated with language abilities, only conversational “turn-taking” is significant when controlling for parental income and education.
Importantly, these results suggest that turn-taking is more predictive of developmental outcomes than socioeconomic status, which certainly gives credence to the hopeful adage that poverty is not destiny.
Second, the study reveals a neural mechanism by which language experience may influence brain development. Specifically, children who experience more conversational turns show greater activation in the brain’s language-processing center, independent of socioeconomic status, cognitive ability, adult word exposure or child vocalization frequency.
In short, this study provides evidence for a direct relationship between brain development and conversational turn-taking throughout the day.
From an academic perspective, this study is important because we now have a direct measure of activation in one of the brain’s primary language areas and its link to an objective assessment of a child’s language experience.
From a practical perspective, this study suggests that engaging with children is more strongly related to their development than their parents’ income or educational level.
Caregivers can use what is at the ready any time they are with children. While changing a diaper, eating together or playing outside — the accumulated experience of language interaction is what’s most important for brain development.
A little talk goes a long way. It’s free, and it can be done any time caregivers are with children.
One of our foundational beliefs at LENA is that “You can’t change what you don’t measure.” LENA is a validated measure of conversational turns, and a tool that can provide feedback to caregivers on the most crucial element of talk: interaction.
Now that we know more about the relationship between interactive talk and brain development, it’s time to amplify the focus of early intervention programs and teach parents and educators strategies for increasing conversational turn-taking in their daily routines.
We’re in the golden age of cognitive science, and we are learning how to leverage technology to boost our children’s development.
By giving adults actionable feedback on conversational turns, we can equip them to make the best use of the one tool to which everyone has access: talk.