Neurobiology of Affiliation

Affiliative bonds, defined as selective and enduring attachments, are a distinctive feature of mammals. The mammalian brain is not fully formed at birth, requiring external regulation of infants’ immature physiological and behavioral systems by parents’ mature systems during moments of social contact. The parent–infant bond thus becomes the critical setting for biosocial maturation; likewise, deprivation or alterations in maternal provisions during early sensitive periods carry lifetime detrimental effects. Through physical proximity, soft touch, and species-typical parenting behavior, the young are ushered into the social world, mastering rules of social exchange and developing neuroendocrine and brain systems that support social participation. In addition to mammalian general processes, early attachments lay the foundation for a host of human-specific social competencies: the ability to feel secure in social ...