Shaping emotion regulation: attunement, symptomatology, and stress recovery within mother-infant dyads.

The foundations of emotion regulation are organized, in part, through repeated interactions with one's caregiver in infancy. Less is known about how stress physiology covaries between a mother and her infant within these interactions, leaving a gap in our understanding of how the biological basis of emotion regulation develops. This study investigated physiological attunement between mothers and their 5-month-old infants, as well as the influence of maternal depression and anxiety, during stress recovery. During the reengagement phase of the Still Face Paradigm, mother-infant dyads exhibited negative attunement, as measured by inverse covariation of respiratory sinus arrhythmia (RSA). Increases in maternal RSA corresponded to decreases in infant RSA, underscoring dyadic adjustment during recovery. Moreover, infant regulation differed as a function of maternal anxiety, with more anxious mothers having infants with higher RSA during reengagement. Implications for the consolidation of regulatory capabilities within the context of the early caregiving relationship are discussed.