Tracing the impact of maternal communication deviance on joint engagement: The mediating role of maternal supportive behaviors

Communication Deviance is a disorganized communicative style that can disrupt shared meaning-making in parent-child interactions and is considered a risk factor for later mental health difficulties. This longitudinal study, conducted in the UK, examined whether maternal Communication Deviance assessed during pregnancy predicted joint engagement and related processes. Participants were 229 mothers (95.9% White British; M = 27.6 years, SD = 6.1). Maternal Communication Deviance was assessed antenatally, and mother-child dyads were observed during play at 30-months. Communication Deviance predicted lower total joint engagement, including supported (β = -.18, p = .007), coordinated (β = -.17, p = .016), and symbol-infused joint engagement (β = -.24, p < .001), and was associated with reduced supportive behaviors (β = -.40, p < .001) and dyadic attunement (β = -.31, p < .001). Mediation analyses indicated that supportive behaviors accounted for the associations between Communication Deviance and joint engagement outcomes. These findings suggest that Communication Deviance may constrain children's opportunities for shared attention and meaning making. The study supports developmental models that highlight early communicative processes as foundational to socio-cognitive and relational development and identifies supportive behaviors as a potential target for interventions promoting early mental health and parent-child interaction. KEY FINDINGS: Higher maternal Communication Deviance during pregnancy predicted less Total, Supported, Coordinated, and Symbol-infused joint engagement at 30 months. Reduced maternal supportive behaviors fully explained the link between Communication Deviance and lower joint engagement and dyadic attunement. Maternal Communication Deviance may act as an early environmental risk factor, highlighting the importance of supporting maternal responsiveness to promote healthy development. STATEMENT OF RELEVANCE: This study examines how maternal Communication Deviance measured during pregnancy predicts joint engagement and dyadic attunement at 30 months, processes central to early socio-cognitive and relational development. By identifying maternal supportive behaviors as a key mechanism linking Communication Deviance to interactional quality, the research highlights a modifiable target for early intervention. Findings advance understanding of early environmental risk factors and inform strategies to support parent-child interactions, directly addressing foundational processes relevant to child and early childhood mental health.