A heightened synchrony between the mother's and infant's facial affect predicts adverse infant development. We know that maternal psychopathology is related to mother-infant facial affect synchrony, but it is unclear how maternal psychopathology is transmitted to mother-infant synchrony. One pathway might be maternal emotion dysregulation. We examined (a) whether maternal emotion dysregulation is positively related to facial affect synchrony and (b) whether maternal emotion dysregulation mediates the effect of maternal psychopathology on mother-infant facial affect synchrony. We observed 68 mothers with mood disorders and their 4- to 9-month-old infants in the Still-Face paradigm during two play interactions. The mother's and infant's facial affect were rated from high negative to high positive, and the degree of synchrony between the mother's and infant's facial affect was computed with a time-series analysis. Emotion dysregulation was measured with the Difficulties in Emotion Regulation Scale, and psychopathology was assessed with the Symptom Checklist-90-Revised. Higher maternal emotion dysregulation was significantly associated with higher facial affect synchrony; emotion dysregulation fully mediated the effect of maternal psychopathology on facial affect synchrony. Our findings demonstrate that maternal emotion dysregulation rather than maternal psychopathology per se places mothers and infants at risk for heightened facial affect synchrony.
