The impact of infant carrying on infant social development: Infant-mother interactions during the still-face task

• In Event: 1-048 - Keep on carrying on: Effects of carrying on infant nutrition, motor development, and social interaction

Integrative Statement

Introduction 
During the first year of an infant’s life, patterns of relating to others are formed based upon his or her interactions with the primary caregiver, usually the biological mother. Adolescent mothers have greater difficulty interacting with their baby; their infants are more likely to have a difficult temperament and their parenting is less sensitive, responsive, or positive. Research suggests that touch, or prolonged physical contact, can promote positive mother-infant interactions.

Hypotheses
The purpose of this study is to assess the potential use of infant carrying practices (i.e., holding or carrying a baby in a cloth carrier that is worn on the body) as an effective intervention to improve infant social development in a sample of adolescent mothers.

Study Population 
Adolescent mothers (Mage = 19.1 years, SD = 2.0; 45% White, 44% Hispanic; 43% <=11th grade) participated in a psychoeducation prevention program and were randomly assigned to one of two conditions at 2 to 4 weeks postpartum: intervention (n = 16; used an infant carrier for one hour a day for 3 months) and control (n = 17; read to their baby).

Methods
When infants were 7 months old (M = 29.0 weeks, SD = 3.4) they participated in the Still-Face (SF) Paradigm with their mothers (2 minutes interaction, 2 minutes still-face, 2 minutes reunification). Videos were coded for observed infant and mother engagement behaviors based on Tronick’s (1978) scoring system, including facial expressions, direction of gaze, and vocalizations.

Results 
Repeated measures ANOVAs and simple effects tests for significant interactions indicated that only infants in the intervention condition showed the SF effect: heightened negative engagement and a reduction of social engagement during the SF phase (see Figure 1). The intervention mothers spent more time in social positive engagement and exaggerated positive engagement (see Figure 2). Infants in the control condition spent less time in social monitoring overall and more time in object/environment engagement during the SF phase. Their mothers were more likely to “give up” in the reunion phase; they showed less social positive and exaggerated social positive engagement and were more withdrawn. Effect sizes were moderate to large.

Discussion 
This study is the first to show that prolonged close physical contact throughout the first months of life influences infants’ early representations for maternal responsiveness. Infants who spent less time in close physical proximity with their young mothers may have learned that their mothers are less responsive to their behaviors, increasing the likelihood that they would ignore their mother or attend to other things in their environment. Lower infant negative engagement overall, and less resistance to the mothers’ bids to reengage during the reunion phase, has been associated with maternal sensitivity. These findings suggest that the consistent use of an infant carrier may increase maternal sensitivity, which plays a critical role in infant social and emotional development. These results add to the growing recognition of infant carrying as a cost-effective and culturally relevant practice that can broadly promote healthy infant social and emotional development.

Author

• Lela Rankin Williams, Arizona State University
  Presenting Author