Exploring the Links between the Quality of Early Mother-Infant Interactions and Child Physiological, Behavioural, and Developmental Outcomes. Do we Understand their Complexity?

Various aspects concerning the quality of mother-infant early interactions have been identified as developmentally supportive, promoting child socio-emotional and cognitive skills or related to less favourable outcomes. This review aims to: 1) an overview of observation-based measures assessing the quality of earliest mother-infant interactions, 2) systematically categorize associated behavioural and developmental outcomes, 3) identify potential gaps, together with promising new directions in research. We conducted systematic searches of SCOPUS, Web of Science, PubMed, Cochrane Library, EBSCO, and Google Scholar, in which 30 articles met the eligibility criteria and were selected. Only empirical papers were included, if the quality of mother-infant interactions was measured by direct observation within the first 8 months of the infant's life. The interaction quality measures were divided into unidirectional ones, focused on maternal contribution to the interaction, and bidirectional ones, describing mutual dynamics during interaction. We found that within the selected literature, unilateral methods were prevalent over the bilateral approach. What is more, we identified a research gap concerning the relationship between bidirectional indices of interaction quality and child physiological and neurodevelopmental outcomes. Further studies are needed to comprehend the cascading relationships, through which interactional experience modulates a baby's physiological response, resulting in specific developmental outcomes.