Revisiting the roots of attachment: A review of the biological and psychological effects of maternal skin-to-skin contact and carrying of full-term infants.

During the early period of hypothesis building and empirical testing of attachment theory, a major emphasis was placed on mother-infant physical contact. In spite of this, mother-infant contact has received scant attention amongst attachment and child development researchers in the past decades. Here, a brief theoretical framework for mother-infant contact is presented, drawing on animal studies as well as human studies of preterm infants and neonates. Salient mechanisms may include an extended sensitive period during early infancy, requiring specific somatosensory stimuli for bio-behavioral homeorhesis; oxytocinergic and epigenetic pathways; kinesthetic stimuli and face-to-face proximity allowing for increased social interaction. Studies of extended human mother-full-term infant physical contact have demonstrated positive effects in multiple domains. For infants, these include sleep organization, temperature and heart rate regulation, behavioral response, crying/colic, socio-emotional development, attachment quality, speech development opportunities and mother-child interactions. For mothers, studies demonstrate improved depressive symptomatology, physiological stress regulation, contingent responsivity, breastfeeding and mother-child interactions. Parent-infant attachment quality has gained prominence as a trauma-resilience factor as well as a predictor of adult physical health. The potential role of mother-infant contact as an attachment promoting intervention as well as future research subjects are discussed. Current evidence supports the original attachment research that early maternal touch provision may influence infant socio-emotional development and attachment quality, with positive implications for mother-child relationship functioning.