Infant-directed communication in Tanna, Vanuatu and Vancouver, Canada

It is known that infant-directed speech (IDS) plays a key role in language development. Previous research, however, has also identified significant variability across societies in terms of how often IDS occurs. For example, some studies report very little IDS in non-western, small-scale societies – including children growing up in small-scale societies in Tanna, Vanuatu. This is surprising given that IDS is widely assumed as a common feature of human caregiving based on research conducted in urbanised populations which are more well-studied. Here, we propose that IDS is only one of a suite of important caregiving behaviours that are produced during interactions with infants, which may vary by culture, perhaps being replaced by other, non-verbal infant-directed behaviours (IDB). We will examine previously collected data consisting of 94 semi-structured 10-min video observations of caregivers and their 18–24 month-old children in rural Tanna, Vanuatu and urban Vancouver, Canada to identify and compare the proportion of time caregivers spend engaging in IDS and IDB during these interactions, both within and between societies. We define IDS as caregiver speech or vocalisations during the interaction with the infant, and we define IDB as non-verbal behaviours that are produced with the infant during the interaction. This study aims to take a step towards a more generalised understanding of language development in children, moving beyond the urban and western societies in which our understanding of development is currently based, and the predicted results will aid in recognising different developmental pathways within multi-cultural communities.