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…

Joint attention (JA) is the purposeful coordination of an individual's focus of attention with that of another and begins to develop within the first year of life. Delayed, or atypically developing, JA is an early behavioural sign of many developmental disabilities and so assessing JA in infancy can improve our understanding of trajectories of…

Caregivers' goals influence their interactions with their children. In this preregistered study, we examined whether directing parents to "teach" their baby versus "learn" from their baby influenced the extent to which they engaged in intrusive (e.g., controlling, adult-centered rather than child-centered), sensitive, warm, or…

This study explores vocal development as an early marker of autism, focusing on canonical babbling rate and onset, typically established by 7 months. Previous reports suggested delayed or reduced canonical babbling in infants later diagnosed with autism, but the story may be complicated. We present a prospective study on 44 infants later diagnosed…

This study examined the characteristics of the vocal behaviors of parents and preterm infants, as compared to their term-born peers, at three months of age. Potential links between specific features of parental IDS and infants' vocal activity were also sought. We analyzed the frequencies and durations of vocalizations and pauses during the dyadic…

School readiness is a topic of great interest to early childhood and maternal child health initiatives, such as the Maternal, Infant, and Early Childhood Home Visiting (MIECHV) programme. However, there is a lack of information about best practices or strategies in home visiting and their relative effectiveness in improving school readiness,…

Purpose: To investigate the language environments experienced by preterm-born infants, this study compared the linguistic and interactive features of parent--infant conversations involving 2-year-old preterm- and term-born infants. The study also explored how mother-infant and father-infant conversations may be differentially affected by…

Infancy is a period of significant change for both the brain and behavior. During the first two years of life, the brain experiences an explosion of synaptic connections and myelination, alongside rapid development in motor, linguistic, and social behavioral abilities. Understanding the relationship between brain development and behavioral…

A growing body of literature has established longitudinal associations between key social cognitive capacities emerging in infancy and children's subsequent theory of mind. However, existing work is limited by modest sample sizes, narrow infant measures, and theory of mind assessments with restricted variability and generalizability. The current…

What are the vocal experiences of children growing up on Malakula island, Vanuatu, where multilingualism is the norm? Long-form audio-recordings captured spontaneous speech behavior by, and around, 38 children (5-33 months, 23 girls) from 11 villages. Automated analyses revealed most children's vocal input came from female adults and other…

Bilingual infants acquire languages in a variety of language environments. Some caregivers follow a one-person-one-language approach in an attempt to not "confuse" their child. However, the central assumption that infants can keep track of what language a person speaks has not been tested. In two studies, we tested whether bilingual and…

As infants interact with the object world, they generate rich information about object properties and functions. Much of infant learning unfolds in the presence of caregivers, who talk about and act on the objects of infant play. Does mother joint engagement correspond to real-time changes in the complexity and duration of infant object…

Infancy, a formative period for development, has been identified as an advantageous time to provide family-centered support for children with delays. Families should be included as stakeholders during development of such interventions to ensure social value. We describe a preliminary randomized controlled trial evaluating Infant Achievements (IA),…

Globally, an estimated 15 million children are born prematurely each year, resulting in a high burden of under-five mortality and neurodevelopmental disability. Kangaroo Mother Care (KMC) is a key intervention to support the development of preterm infants. However, evidence on the impact of KMC in routine care settings remains limited. This paper…

Infants are sensitive to statistics in spoken language that aid word-form segmentation and immediate mapping to referents. However, it is not clear whether this sensitivity influences the formation and retention of word-referent mappings across a delay, two real-world challenges that learners must overcome. We tested how the timing of referent…