Written by Written by Melanie Soderstrom in consultation with article co-authors Eon-Suk Ko, Amanda Seidl, and Alejandrina Crista
It has long been known that adults’ speech patterns unconsciously become more similar over the course of a conversation, but do children converge in this way with their caregivers? Across many areas of child development, children’s imitation of caregivers has long been understood to be an important component of the developmental process. These concepts are similar, but we tend to think of imitation as one-sided and static, while convergence is more dynamic and involves both interlocutors influencing each other. In our study, we set out to examine how duration and pitch characteristics of vocalizations by 1- and 2-year-olds and their caregivers dynamically influence each other in real-world conversational interactions.
We recorded 13 mothers and their children using LENA, a system for gathering full-day recordings, which also provides an automated tagging of the audio stream into speakers. We analyzed pitch and duration characteristics of these segments both within and across conversational exchanges between the mother and child to see whether mothers and children modulated the characteristics of their speech based on each other’s speech. Instead of examining mother-child correlations across mother-child dyads, as previous studies have done, we examined correlations within a given dyad, across conversations. We found small, but significant correlations, particularly in pitch measures, suggesting that mothers and children are dynamically influencing each other’s speech characteristics.
We also looked at who started the conversation, and measured mother and child utterance durations and response latencies (i.e., how quickly mothers responded to their child’s utterance and vice versa). Overall, unsurprisingly, mothers produced longer utterances and shorter responses latencies (faster responding) than their children. However, both the mothers and the children produced longer utterances and shorter response latencies in conversations that they themselves initiated. This finding is exploratory, but suggests that providing children with the conversational “space” to initiate conversations may lead to more mature vocalization, and may therefore be beneficial for the language-learning process.