Stephen W. Porges, PhD, is Distinguished University Scientist at Indiana University, where he directs the Trauma Research Center within the Kinsey Institute. He holds the position of Professor of Psychiatry at the University of North Carolina and Professor Emeritus at the University of Illinois at Chicago and the University of Maryland. He served as president of both the Society for Psychophysiological Research and the Federation of Associations in Behavioral & Brain Sciences and is a former recipient of a National Institute of Mental Health Research Scientist Development Award. He has published more than 250 peer-reviewed scientific papers across several disciplines including anesthesiology, biomedical engineering, critical care medicine, ergonomics, exercise physiology, gerontology, neurology, neuroscience, obstetrics, pediatrics, psychiatry, psychology, psychometrics, space medicine, and substance abuse. In 1994 he proposed the Polyvagal Theory. The theory provides insights into the mechanisms mediating symptoms observed in several behavioral, psychiatric, and physical disorders including autism, anxiety, depression, ADD, PTSD, and schizophrenia. His research has led to the development of innovative interventions designed to stabilize behavioral and psychological states and to stimulate spontaneous social behavior that are being applied to autism and other clinical diagnoses.