Co-sleeping as a proximal context for infant development: The importance of physical touch.

Co-sleeping is a complex familial phenomenon that has yet to be well understood by Western scientists. This paper provides an interdisciplinary review of research from anthropology, nursing, pediatrics, sociology, social work, public health, family studies, and psychology to focus on the role of physical touch in the context of co-sleeping, and how close physical contact in this context affects infants and their caregivers. Including an anthropological, evolutionary view of co-sleeping with other perspectives highlights it as an experience-expectant proximal context for infant growth and development. From this view, the importance of physical contact and touch in the nighttime caretaking microenvironment of co-sleeping becomes a central question, rather than an artifactual byproduct of "unhealthy" sleep arrangements. Rather than trying to eliminate co-sleeping, public health messages for parents would likely benefit from a more culturally-sensitive approach that focuses on advising how to co-sleep safely for families choosing it. For families trying to retain physical closeness between parent(s) and infants in the context of modern (especially Western) infant care practices that have reduced this physical contact, co-sleeping can be an important developmental context for encouraging and engaging in sensitive and responsive caregiving and providing a context for maternal-infant physiological synchrony and regulation.