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.
Attachment in adults
Mary Ainsworth and John Bowlby founded modern attachment theory on studies of children and their caregivers. Children and caregivers remained the primary focus of attachment theory for many years. Then, in the late 1980s, Cindy Hazan and Phillip Shaver applied attachment theory to adult relationships. Hazan and Shaver noticed that interactions between adults shared similarities to interactions between children and caregivers. For example, romantic or platonic partners desire to be close to one another. Adults feel comforted when their attachments are present and anxious or lonely when they are absent. Romantic relationships, for example, serve as a secure base that help people face the surprises, opportunities, and challenges life presents. Similarities such as these led Hazan and Shaver to extend attachment theory to adult relationships.