Abstract
Understanding the impact that early psychosocial neglect has on the course of human development has implications for the millions of children around the world who are living in contexts of adversity. In the US, approximately 76% of cases reported to child protective services involve neglect; world-wide, there are more than 150 million orphaned or abandoned children, including 10.5 million orphaned because of COVID-19. In much of the world, children without primary caregivers are reared in institutional settings. We review two decades of research based on the only randomized controlled trial of foster care as an alternative to institutional care. We report that children randomly assigned to continued care as usual (institutional care) suffer from persistent deficits in social, cognitive, and emotional development, and show evidence of disruptions in brain development. By contrast, children randomly assigned to foster care show improvements in most domains of functioning, although the degree of recovery is in part a function of how old they were when placed into foster care and the stability of that placement. These findings have important implications for understanding critical periods in human development, as well as elucidating the power of the psychosocial environment in shaping multiple domains of human development.