and Later Behavior
Stephen W. Porges
Jane A. Doussard-Roosevelt
University of Maryland
During early infancy, physiological vulnerabilities associated with medical risk (low birthweight, fetal distress, neonatal hypoxia, etc.) are assumed to be potent marker variables capable of predicting difficulties in developmental outcome (e.g., mental retardation and difficulties in learning, poor motor coordination, attention problems, and poor social interactions). However, the specific physiological mechanisms that promote or ameliorate subsequent developmental difficulties have not been identified. Why two children experiencing the same specific risk factors at birth or during early infancy have different outcomes is not well understood. Vague statements regarding the complex interaction between the infant and postpartum environmental factors are often provided in place of an explanation. In the child development literature, the role of the nervous system in the regulation of stress responses has received little attention. In this chapter, we propose that the central regulation of the autonomic nervous system plays a critical role in the child's ability to respond adaptively to stress events and to organize behavioral outcomes. The chapter is based on the hierarchical model of neurobehavioral organization proposed by Porges ( 1983) and incorporates portions of the recent Polyvagal Theory ( Porges, 1995).
Research on stress in adults has often focused on the description of events that are considered stressful (death of a spouse, loss of a job, etc.) and not on the functional impact of these events on physiology. With adults and older children, clinical interview techniques effectively elicit the patients'