Disorganized attachment is the most extreme type of an insecure attachment relationship. Main and Solomon (1990) used the term disorganized/ disoriented attachment (D) to describe patterns of infant behaviour during the Strange Situation which seemed odd and lacked an organized strategy with respect to the attachment figure.

Disorganized attachment has been associated with the infant’s experience of prolonged or repeated separation from the caregiver, but it has also been suggested that attachment disorganization is a constitutional or even genetic disorder. Approximately 80 percent of maltreated infants show this type of attachment. Disorganized attachment is also found with high frequency in infants whose mothers are alcoholics or depressed (in a bipolar way), and in families with high marital conflict (for a meta-analytic review, see Van IJzendoorn, Schuengel, & Bakermans-Kranenburg, 1999).
Disorganized attachments have also been found in children of parents who struggle with unresolved loss or other trauma. Main and Hesse (1990) have suggested that infants develop disorganized attachment when they experience the parent as frightening or frightened, and that the essence of disorganized attachment is fright without solution. When the only possible base from which to explore the world (the parent) is at the same time the source of fear, the child is placed in an irresolvable paradoxical situation, with disorganized attachment as a result.

In the current research program, we test the various models explaining attachment disorganization in different target populations, e.g. twins and adopted children, nursery-reared chimpanzees, children with Autistic Spectrum Disorder, and grandchildren of Holocaust survivors, and maltreated children.