Attachment, exploration and separation: Illustrated by the behaviour of one-year-olds in a strange situation. The significance of insecure attachment and disorganization in the development of children...Attachment, exploration and separation: Illustrated by the behaviour of one-year-olds in a strange situation. The significance of insecure attachment and disorganization in the development of children’s externalizing behavior: A meta‐analytic study. The significance of insecure and disorganized attachment for children’s internalizing symptoms: A meta‐analytic study. Attachment security in infancy: A preliminary study of prospective links to brain morphometry in late childhood.