RESPIRATORY SINUS ARRHYTHMIA AND SOCIAL-INTERACTION PATTERNS IN PRETERM NEWBORNS

Recent evidence suggests that the amplitude of respiratory sinus arrhy thmia (RSA) may be a useful predictor of cognitive and affective devel opment in high-risk infants. Stability and relations among RSA and beh avioral measures were studied in healthy and sick (respiratory and/or central nervous system disorders) preterm newborns at approximately 35 and 42 weeks postconceptional age (PCA). The Hobel Neonatal Complicat ions Factor score was used to measure the extent of neonatal illnesses potentially associated with subsequent developmental risk. At each ag e, an electrocardiogram (ECG) was recorded for 10 min each during acti ve sleep and social interaction. The amplitude of RSA was derived from ECG using the Porges (1986) method to estimate cardiac vagal tone (V) . The study examined the relationship between neonatal RSA and simulta neous videotaped recordings of infants' focused attention, unfocused a ltertness, and distressed/avoidant behavior under two conditions: (a) during a standardized protocol for responsive social interaction with an examiner at 35 and 42 weeks; and (b) during an unstructured interac tion session with their mothers at 42 weeks. At 35 weeks, RSA was rela ted to neonatal behavior with an examiner. In addition, the 35-week RS A and behavioral measures were predictive of maternal and infant inter action behavior at 42 weeks. These preliminary findings suggest that a n assessment protocol which includes social interaction behavior and R SA may be useful in identifying infants who are at greatest risk for d evelopmental and relationship disturbances.