Developmental psychology
Attachment theory, originally developed by John Bowlby, focuses on the importance of open, intimate, emotionally meaningful relationships. Attachment is described as a biological system or powerful survival impulse that evolved to ensure the survival of the infant. A child who is threatened or stressed will move toward caregivers who create a sense of physical, emotional and psychological safety for the individual. Attachment feeds on body contact and familiarity. Later Mary Ainsworth developed the Strange Situation protocol and the concept of the secure base.
Social emotional development
Attachment refers to the strong bond that individuals develop with special people in their lives. Though we can have attachment relationships with significant others in adulthood, such as marital partners, most humans’ first and most influential attachment is with their primary caregiver(s) as infants. John Bowlby and Mary Ainsworth first delineated and tested attachment theory as an evolutionarily informed process in which the emotional ties to a caregiver are adaptive for survival. Their research supported the presence of four stages of attachment formation: