The development of the infant and interactions between the mother and infant

The social environment, particularly the one created together by the mother and infant, directly affects gene-environment interactions and, thereby, has long-enduring effects. The development of the infant is largely influenced by the mother’s innate disposition and the way she was raised. Attachment theory, proposed by Bowlby, acknowledges a conception of the mother-infant relationship as the dominant model of human social-emotional development. From birth onward, infants use their maturing motor and developing sensory capacities, especially smell, taste, and touch to interact with the social environment. At around 8 weeks of age, there is a dramatic progression of social and emotional capacities. Within episodes of mutual gaze, the mother and infant engage in nonconscious and spontaneous facial, vocal, and gestural communications. The mother’s face and posture filled with affection give the infant a sense of security. Such highly arousing, affect-laden, face-to-face interactions allow the infant to be exposed to high levels of social and cognitive information. The attachment steadfastly forms through these emotional interactions. Brain mass increases rapidly during the first two years after birth, especially the right brain, has an outstanding development as the attachment is reinforced by emotional interactions. The right brain is dominant for the regulation of fundamental endocrinologic, immunologic, and cardiovascular functions, thereby controlling vital functions that support survival. Thus, these affectionate interactions between the mother and infant profoundly related to the infant’s psychological development as well as the mental and physical functions in later life. Moreover, when a girl has grown up and has a new baby, her right brain will communicate with the new baby. It is the right brain that experienced the formation of the attachment between her own mother and herself during her infancy. The interactions of right brain-to-right-brain between the infant and mother occur again.

（Pediatrics in Review Vol.26No.6 2005）

Considering this importance of affectionate interactions between the mother and infant, we make an effort not only to diagnose and treat children’s diseases but also to provide health care to mothers, pregnant women, and people who are planning to be parents.