How do languages become learnable for young children? Our latest study, “Immature vocalizations elicit simplified adult speech across multiple languages,” is now out in Current Biology!
We’ve long known that infants and toddlers are incredible learners. Despite their immaturity, do they play an active role in their learning? We found that the answer is yes. Our new study shows that infants’ and toddlers’ early babbling and immature speech functions to facilitate caregivers’ reactions that help them learn. When caregivers respond to immature speech, they speak in simpler sentences. This “simplification effect” from caregivers makes language more learnable! We found this effect in 13 different languages, including Tseltal Mayan, where engaging in face-to-face interaction with infants is rare. What such cross-cultural behavior implies is that this “simplification effect” may be widespread and present in many more languages than the 13 we studied.
We found that the timing of parents’ responses matters. Parents simplified their speech significantly more when they responded immediately (i.e. contingently) after their child’s babbling and speech. In contrast, infant-directed speech that was not contingent was not simplified.
Read more about our findings here: https://news.cornell.edu/stories/2025/02/power-babble-babies-elicit-simpler-speech-adults