Maternal sensitivity as a predictor of change in respiratory sinus arrhythmia activity from infancy to toddlerhood

This study examined whether parental sensitivity during distressing and non‐distressing mother–infant interactions predicts changes in young children's respiratory sinus arrhythmia (RSA) activity. Baseline RSA levels were collected from 83 children (49% female, 51% male) when children were 7 and 18 months old. Children's RSA reactivity and RSA recovery during the still‐face paradigm were collected when children were 7 months and during the strange situation procedure at 18 months. Controlling for stability of RSA activity over time, maternal sensitivity during distressing interactions at 7 months predicted changes in children's baseline RSA levels (β = −0.30) and children's RSA recovery (β = 0.25). Young children who experienced higher levels of sensitivity at 7 months had lower resting RSA levels and exhibited greater RSA recovery at 18 months. These results suggest that changes in young children's RSA activity are meaningfully related to their early caregiving experiences.Highlights We examined whether maternal sensitivity during infancy predicts changes in children's RSA activity from infancy to toddlerhood. Children who experienced higher levels of maternal sensitivity during infancy showed greater RSA recovery from a stressor during toddlerhood. Children who experienced higher levels of maternal sensitivity during infancy had lower resting RSA levels during toddlerhood.