PT - JOURNAL ARTICLE AU - Drew H. Abney AU - Elizabeth B. daSilva AU - Bennett I. Bertenthal TI - Associations between Infant-Mother Physiological Synchrony and 4- to 6-Month-Old Infants’ Emotion Regulation AID - 10.1101/2021.04.13.439498 DP - 2021 Jan 01 TA - bioRxiv PG - 2021.04.13.439498 4099 - http://biorxiv.org/content/early/2021/04/14/2021.04.13.439498.short 4100 - http://biorxiv.org/content/early/2021/04/14/2021.04.13.439498.full AB - In this study we assessed whether physiological synchrony between infants and mothers contributes to infants’ emotion regulation following a mild social stressor. Infants between 4- to 6-months of age and their mothers were tested in the Face-to-Face-Still-Face paradigm, and were assessed for behavioral and physiological self-regulation during and following the stressor. Physiological synchrony was calculated from a continuous measure of respiratory sinus arrhythmia (RSA) enabling us to cross-correlate the infants’ and mothers’ RSA responses. Without considering physiological synchrony, the evidence suggested that infants’ distress followed the prototypical pattern of increasing during the Still Face episode and then decreasing during the Reunion episode. Once physiological synchrony was added to the model, we observed that infants’ emotion regulation improved if mother-infant synchrony was positive, but not if it was negative. This result was qualified further by whether or not infants suppressed their RSA response during the Still Face episode. In sum, these findings highlight how individual differences in infants’ physiological responses contribute significantly to their self-regulation abilities.Competing Interest StatementThe authors have declared no competing interest.