The Impact of Maternal Mental Health on Synchrony in Mother-Infant Interactions

Abstract

This thesis aims to explore the impact of maternal mental health on mother-infant interactions. Objective one is to explore mothers' perceptions of poor mental health and its influence on their infants. Objective two is to describe the synchrony of visual attention and facial expression between the dyad. Objective three is to analyse durations of maternal facial expressions and to compare facial expression transitions between non-depressed and sub- clinically depressed mothers during these interactions, with the goal of informing context - specific interventions for a vulnerable population in South Africa. This PhD used mixed methods. A qualitative study with fifteen Sowetan mothers, in two focus groups, explored postpartum mental health experiences and how these experiences affected their bonding with their infants. Thematic analysis identified key contributors to mental health challenges. For the quantitative studies, 57 mother-infant interactions were recorded during free- play with head-mounted cameras. Synchrony in visual attention and facial expressions was analysed using Observer XT 16 ® software focusing on behavioural frequency, duration and lag sequencing. Time-series analyses over 3 second intervals defined synchrony. Facial expression transitions between non-depressed and sub-clinically depressed mothers were compared using 1, 2 and 3-second time lags. A transition was defined as a shift from neutral to an emotional expression within 3 seconds. EPDS scores of 6-13 indicated sub-clinical depression. Paternal denial, family conflict, financial hardship, and lack of community support were perceived to contribute to poor maternal mental health. A theme of maternal persecution emerged. Behavioural micro-analysis of interactional exchanges revealed that infants looked at their mothers 47% of the time, mothers looked at their infants 92% of the time. Limited behavioural variation complicated synchrony measurement. When focusing on transitions in expressions, sub-clinically depressed mothers were 84% less likely to exhibit a positive facial expression before transitioning to a smile as compared to non-depressed mothers. A mother’s inward-directed anger can erode her self-trust, and when depression affects the relationship, it undermines trust within the dyad. Despite this, mothers showed a strong desire to be ‘good enough’ and actively sought to connect with their infants. Early intervention is essential, particularly in vulnerable settings with limited research. The study calls for culturally sensitive support for mothers and their infants, with a focus on promoting the virtues of trust and hope.