How Social Contingency Shapes Early Child-Caregiver Interactions

Child-caregiver interactions involve mutual anticipation and contingent responses where each interactant adapts their behaviour in response to social feedback from the other interactant. This dissertation focuses on two features that originate in these social feedback loops and are highly characteristic of early child-caregiver interactions: speech content (i.e., infant-directed speech, IDS) and temporal structure (i.e., turn-taking). To map out the sampling space of previous studies and to gain a better understanding of how social contingency shapes the form and structure of early child-caregiver interactions, I conduct systematic reviews, meta-analyses, and critically leverage cumulative science practices. Study I is a systematic review and Bayesian meta-analysis of the acoustic features of IDS. The study aims to investigate how the acoustic features of IDS differ across infant ages and languages and to understand these results in relation to the purported functions of IDS. Study II goes hand in hand with the meta-analysis on IDS and provides a comprehensive acoustic analysis of the prosodic and vocalic properties of Danish caregivers’ spontaneous IDS and adult-directed speech (ADS). Study III is a systematic review and Bayesian meta-analysis on the developmental trajectory of infants’ turn-taking abilities, which attempts to identify key moderators affecting response latencies to gain a better understanding of the cognitive mechanisms underlying children’s turn-taking abilities. These three studies not only contribute to our understanding of how social contingency shapes both the speech content and temporal structure of early child-caregiver interactions, but also provide suggestions for future strands of research and theory development.