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.
Attachment theory
Beginning in 1970, a series of expansions were added to Ainsworth's original patterns. They include the following: B4 (1970), A/C (1985) D/disorganized (1986), B5 (1988, 1992) A+, C+, & Depressed (1992, 2010). At later ages, additional categories have been described. Each of these patterns reflects a different kind of attachment relationship of the infant with the mother/caregiver. An infant may have a different pattern of attachment to each parent as well as to alternate caregivers. Pattern of attachment is thus not a part of the infant, but is characteristic of the protective and comforting quality of a specific relationship. These attachment patterns are associated with behavioral patterns and can help further predict a child's future personality.