Attachment and Health
John Bowlby and Mary Ainsworth developed attachment theory in the 1960s while investigating the effects of maternal separation on infant development. The development of the Strange Situation task in 1965 by Ainsworth and Wittig allowed researchers to systematically investigate the attachment system operating between children and their parents. The Strange Situation involves separating infant-parent dyads and observing infant behaviours upon reunion. Infant behaviour tended to follow patterns, leading to the development of three attachment categories: Secure, Anxious-Avoidant, and Anxious-Resistant. In 1990, Ainsworth added a new category, championed by Mary Main, called Disorganized/Disoriented attachment, characterized by its less reliable pattern of behaviour.
Caring in intimate relationships
Attachment theory, an influential theoretical framework for the study of intimate relationships and personality development, argues that all humans are born with the capacity and motivation to engage in caregiving behaviours aimed at providing protection and support to close others. These behaviours are organized by an innate behavioural system, called the "caregiving system", which is believed to have emerged over the course of primate evolution to ensure the survival of vulnerable offspring. That is, because infants in many primate species, including humans, are highly altricial ("i.e.", developmentally immature and helpless at birth), they cannot survive without caregiver support and protection. Attachment theory proposes that this evolutionary pressure favoured the emergence of the caregiving behavioural system, which functions to safeguard the vulnerable dependent from harm by providing him or her with protection, comfort, and help during times of threat or need. Although this system was first conceptualized in child–parent bonds, its operation has since been established in adult intimate relationships, where both partners may occasionally take on the role of caregiver.