Understanding
Conversational Turns

What are conversational turns?


Conversational turns are simple back-and-forth alternations between a child and an adult. LENA technology counts that a turn has occurred when an adult speaks and a child follows, or vice versa, with no more than five seconds in between. Any speech-like, non-cry sound counts as a turn — from an infant's coos to a toddler's words (either real or made up). Conversational turns are LENA’s proxy for quality “serve and return” interactions.


How are conversational turns related to
early brain development?


They may be simple, but conversational turns are also incredibly powerful. Conversational turns are among the most predictive metrics of child outcomes.

Importantly, there's overwhelming evidence that conversational turns have more brain-building power than adult words alone. (That’s why you won’t see references to the “30 million word gap” on our website — the term has increasingly become outdated due to the latest science and doesn't adequately capture the complexities of the early talk gap.)

Video highlights: Recent studies highlight the importance of conversational turns


In 2018, Dr. Rachel Romeo and a team of researchers at MIT and Harvard published two papers examining how conversational turns relate to children’s brain structure and brain function. The first paper shed light into the underlying neural mechanism that makes conversational turns so critical for early brain development, identifying a relationship between conversational turns and activation in Broca’s area, a language center in the brain. The findings in the second paper indicate that conversational turns strengthen white matter “information highways” in the brain, allowing the whole brain to work together better.

Watch a webinar with these researchers


Dr. Jill Gilkerson, LENA's Chief Research and Evaluation Officer, led a team that published the results of a 10-year longitudinal study in the fall of 2018, exploring how conversational turns relate to a child’s long-term outcomes. The study found a correlation between the amount of conversation turns experienced between 18-24 months of age and a child’s verbal abilities, language skills, and IQ scores in adolescence.

Dr. Kim Noble led a team at Teachers College, Columbia University, to study the relationship between family socioeconomic background, children’s brain structure, and children’s reading skills. The study, published in early 2019, found that children who experienced more conversational turns had greater surface area on the left perisylvian cortex, and in turn, better reading skills.


Dr. Esteban Gómez Muzzio and Dr. Katharine Strasser published the results of their study about the importance of conversational turns for socioemotional development in 2021. The paper, conducted through the Pontificia Catholic University of Chile, found a strong correlation between conversational turns at 18 months of age and socioemotional development at 30 months of age.


Stream a webinar about socioemotional development




Download the latest reports
about conversational turns

Download Inside Early Talk
Inside Early Talk

Data analyses from over 10,000 children annually impacted by LENA’s programs have put us in the position to answer important questions about language environments in early childhood education. For instance, we’ve established 40 conversational turns per hour as a new benchmark for caregivers.

Download Inside Early Talk

and Stream the webinar here.

Download Inside Early Talk


Proving the Power of Talk report


Proving the Power of Talk

The past decade has seen widespread acceptance that early language plays a critical role in babies’ brain growth and in their subsequent success in school and in life. Read a summary of the latest research on the power of early talk!

Download Proving the Power of Talk



LENA programs put research into action, changing communities for the better worldwide.

LENA technology — the only validated measure of conversational turns in the world — powers the research discoveries that prove the importance of conversational turns. The same technology also powers LENA's programs for parents and teachers, helping caregivers everywhere tap into the brain-building potential of conversational turns.

If you're interested in learning more about bringing a LENA program to your community, please send us an email or schedule a meeting. We also invite you to complete a program readiness assessment to see where you are on your LENA journey. If you're a researcher and you want to learn more about incorporating LENA technology into your work, LENA SP is the tool for gaining early language insights in research and clinical applications.

Complete a readiness assessment