A comparison of dyadic interactions and coping with still-face in healthy pre-term and full-term infants

Pre-term birth has a significant impact on infants' social and emotional competence, however, little is known about regulatory processes in pre-term mother-infant dyads during normal or stressful interactions. The primary goals of this study were to investigate the differences in infant and caregiver interactive behaviour and dyadic coordination of clinically healthy pre-term compared to full-term infant-mother dyads and to examine pre-term infants' capacity for coping with stress using the face-to-face still-face paradigm (FFSF). Fifty mother-infant dyads, including 25 pre-term infants and 25 full-term infants were videotaped during the FFSF. All infants were 6-9 months of age (corrected for gestational age in the pre-term group). Infant and maternal socio-emotional expressivity and self-regulatory behaviours were coded and measures of dyadic coordination (Matching, Reparation Rate, and Synchrony) were calculated. There were no significant differences in infant and caregiver socio-emotional behaviours between the two groups and both groups demonstrated the still-face (SF) effect and the reunion effect. There was a difference in self-regulatory behaviour. Pre-term infants were more likely than full-term infants to use distancing (e.g., by turning away, twisting, or arching) from their mothers during the FFSF. Additionally, during the Reunion episode of the FFSF pre-term infants showed more social monitoring compared to full-term infants. Regardless of the birth status, the dyads showed less coordination and a slower rate of reparation during the Reunion episode than during the Play episode. The higher proportion of distancing in the pre-term group and the increase in social monitoring suggest that even in normal interactions pre-term infants may experience a higher level of stress and have less capacity for self-regulation compared to the full-terms and that pre-term infants appear to use a compensatory strategy of increased social monitoring to cope with the stress of renegotiating the interaction during Reunion. The findings suggest that pre-term infants have different regulatory and interactive capacities than full-term infants.