Relational psychophysiology: lessons from mother-infant physiology research on dyadically expanded states of consciousness.

The authors illustrate how their work on mother-infant "relational psychophysiology" might inform psychotherapy research. They examined psychophysiology in 18 mother-infant dyads (infants' age: 5 months) during normal interaction and a still-face perturbation. They measured respiratory sinus arrhythmia (RSA) as an index of emotion regulation and explored whether skin conductance (SC) concordance, previously linked to therapist empathy, occurs in mothers and infants. During the still-face episode, SC concordance correlated to infant negative engagement. Upon reengagement, when mothers often soothe their infants, concordance instead correlated to behavioral synchrony, an index of maternal sensitivity. Furthermore, maternal RSA became correlated to infant negative engagement. These findings suggest that a mother trying to calm her infant calms herself physiologically and her sensitivity on a behavioral level becomes coherent physiologically. Implications for psychotherapy research are discussed.